Features

Provides accurate measurement
of available charge in NiCd,
NiMH, Li-Ion, and lead-acid
batteries

Supports SBS Smart Battery
Data Specification v1.1

Supports the 2-wire SMBus v1.1
interface with PEC or 1-wire
HDQ16

Reports individual cell voltages

Monitors and provides control to
charge and discharge FETs in
Li-Ion protection circuit

Provides 15-bit resolution for
voltage, temperature, and cur-
rent measurements

Measures charge flow using a
V-to-F converter with offset of
less than 16

V after calibration

Consumes less than 0.5mW oper-
ating

Drives a 4- or 5-segment LED
display for remaining capacity in-
dication

28-pin 150-mil SSOP

General Description

The bq2060 SBS-Compliant Gas
Gauge IC for battery pack or
in-system installation maintains an
accurate record of available charge in
rechargeable batteries. The bq2060
monitors capacity and other critical
battery parameters for NiCd, NiMH,
Li-Ion, and lead-acid chemistries.
The bq2060 uses a V-to-F converter
with automatic offset error correction
for charge and discharge counting.
For voltage, temperature, and current
reporting, the bq2060 uses an A-to-D
converter.

The onboard ADC also

monitors individual cell voltages in a
Li-Ion battery pack and allows the
bq2060 to generate control signals
that may be used in conjunction with
a pack supervisor to enhance pack
safety.

The bq2060 supports the smart bat-
tery data (SBData) commands and
charge-control functions. It communi-
cates data using the system manage-
ment bus (SMBus) 2-wire protocol or
the Benchmarq 1-wire HDQ16 proto-
col. The data available include the
battery's remaining capacity, temper-
ature, voltage, current, and remain-
ing run-time predictions. The bq2060

provides

LED

drivers

and

push-button input to depict remaining
battery capacity from full to empty in
20% or 25% increments with a 4 or
5-segment display.

The bq2060 works with an external
EEPROM. The EEPROM stores the
configuration information for the
bq2060, such as the battery's chemis-
try, self-discharge rate, rate compen-
sation factors, measurement calibra-
tion, and design voltage and capacity.
The bq2060 uses the programmable
self-discharge rate and other compen-
sation factors stored in the EEPROM
to accurately adjust remaining capac-
ity for use and standby conditions
based on time, rate, and temperature.
The bq2060 also automatically cali-
brates or learns the true battery ca-
pacity in the course of a discharge cy-
cle from near full to near empty lev-
els.

The REG output regulates the operat-
ing voltage for the bq2060 from the
battery cell stack using an external
JFET.

bq2060

SBS v1.1-Compliant Gas Gauge IC

HDQ16

Serial communication
input/output

ESCL

Serial memory clock

ESDA

Serial memory data and
address

RBI

REG

Regulator output

OUT

EEPROM supply output

Supply voltage

Ground

DISP

Display control input

LED

LED display segment outputs

28PN2060.eps

28-Pin 150-mil SSOP

2
3

7
8

27
26

25
24
23

11
12

18
17

SMBC

SMBD
VCELL

VCELL

SRC

TS
THON
CVON
CFC

DFC

HDQ16

ESCL

ESDA

RBI

REG

OUT

DISP

LED

DFC

Discharge FET control

CFC

Charge FET control

VON

Cell voltage divider con-

trol

THON

Thermistor bias control

Thermistor voltage input

SRC

Current sense input

Charge-flow sense resistor
inputs

VCELL

Single-cell voltage inputs

SMBD

SMBus data

SMBC

SMBus clock

SLUS035DSEPTEMBER 2001

Pin Connections

Pin Names

Pin Descriptions

HDQ16

Serial communication input/output

Open-drain bidirectional communications
port

ESCL

Serial memory clock

Output to clock the data transfer between
the bq2060 and the external nonvolatile
configuration memory

ESDA

Serial memory data and address

Bidirectional pin used to transfer address
and data to and from the bq2060 and the
external nonvolatile configuration memory

RBI

Register backup input

Input that provides backup potential to the
bq2060 registers during periods of low oper-
ating voltage. RBI accepts a storage capaci-
tor or a battery input.

REG

Regulator output

Output to control an n-JFET for V

regu-

lation to the bq2060 from the battery poten-
tial

OUT

Supply output

Output that supplies power to the external
EEPROM configuration memory

Supply voltage input

Ground

DISP

Display control input

Input that controls the LED drivers
LED

LED

LED

LED display segment outputs

Outputs that each may drive an external
LED

DFC

Discharge FET control output

Output to control the discharge FET in the
Li-Ion pack protection circuitry

CFC

Charge FET control output

Output to control the charge FET in the
Li-Ion pack protection circuitry

CVON

Cell voltage divider control output

Output control for external FETs to connect
the cells to the external voltage dividers
during cell voltage measurements

THON

Thermistor bias control output

Output control for external FETs to connect
the thermistor bias resistor during a tempera-
ture measurement

Thermistor voltage input

Input connection for a thermistor to monitor
temperature

SRC

Current sense voltage input

Input to monitor instantaneous current

Sense resistor inputs

Input connections for a small value sense
resistor to monitor the battery charge and
discharge current flow

VCELL

Single-cell voltage inputs

Inputs that monitor the series element cell
voltages

SMBD

SMBus data

Open-drain bidirectional pin used to trans-
fer address and data to and from the
bq2060

SMBC

SMBus clock

Open drain bidirectional pin used to clock
the data transfer to and from the bq2060

bq2060

Functional Description

General Operation

The bq2060 determines battery capacity by monitoring
the amount of charge input or removed from a recharge-
able battery. In addition to measuring charge and dis-
charge, the bq2060 measures battery voltage, tempera-
ture, and current, estimates battery self-discharge, and
monitors the battery for low-voltage thresholds.

The

bq2060 measures charge and discharge activity by moni-
toring the voltage across a small-value series sense re-
sistor between the battery's negative terminal and the
negative terminal of the battery pack.

The available

battery charge is determined by monitoring this voltage
and correcting the measurement for environmental and
operating conditions.

Figure 1 shows a typical bq2060-based battery pack ap-
plication. The circuit consists of the LED display, volt-
age and temperature measurement networks, EEPROM
connections, a serial port, and the sense resistor. The
EEPROM stores basic battery pack configuration infor-
mation and measurement calibration values.

The

EEPROM must be programmed properly for bq2060 op-
eration. Table 10 shows the EEPROM memory map and
outlines the programmable functions available in the
bq2060.

The bq2060 accepts an NTC thermistor (Semitec 103AT)
for temperature measurement.

The bq2060 uses the

thermistor temperature to monitor battery pack temper-
ature, detect a battery full charge condition, and com-
pensate for self-discharge and charge/discharge battery
efficiencies.

Measurements

The bq2060 uses a fully differential, dynamically bal-
anced voltage-to-frequency converter (VFC) for charge
measurement and a sigma delta analog-to-digital con-
verter (ADC) for battery voltage, current, and tempera-
ture measurement.

Voltage, current, and temperature measurements are
made every 22.5 seconds, depending on the bq2060 op-
erating mode. Maximum times occur with compensated
EDV, mWh mode, and maximum allowable discharge
rate. Any AtRate computations requested or scheduled
(every 20 seconds) may add up to 0.5 seconds to the time
interval.

Charge and Discharge Counting

The VFC measures the charge and discharge flow of the
battery by monitoring a small-value sense resistor
between the SR

and SR

pins as shown in Figure 1.

The VFC measures bipolar signals up to 250mV. The
bq2060 detects charge activity when V

= V

SR2

SR1

is positive and discharge activity when V

= V

SR2

SR1

is negative.

The bq2060 continuously integrates

the signal over time using an internal counter.

The

fundamental rate of the counter is 6.25

Vh.

Offset Calibration

The bq2060 provides an auto-calibration feature to cancel
the voltage offset error across SR

and SR

for maximum

charge measurement accuracy. The calibration routine is
initiated by issuing a command to ManufacturerAccess().
The bq2060 is capable of automatic offset calibration down
to 6.25

V. Offset cancellation resolution is less than 1

Digital Filter

The bq2060 does not measure charge or discharge
counts below the digital filter threshold. The digital fil-
ter threshold is programmed in the EEPROM and
should be set sufficiently high to prevent false signal de-
tection with no charge or discharge flowing through the
sense resistor.

Voltage

While monitoring SR

and SR

for charge and discharge

currents, the bq2060 monitors the battery-pack poten-
tial and the individual cell voltages through the
VCELL

VCELL

pins. The bq2060 measures the pack

voltage and reports the result in Voltage(). The bq2060
can also measure the voltage of up to four series ele-
ments in a battery pack. The individual cell voltages
are stored in the optional Manufacturer Function area.

The VCELL

VCELL

inputs are divided down from the

cells using precision resistors, as shown in Figure 1. The
maximum input for VCELL

VCELL

is 1.25V with re-

spect to V

. The voltage dividers for the inputs must be

set so that the voltages at the inputs do not exceed the
1.25V limit under all operating conditions. Also, the di-
vider ratios on VCELL

VCELL

must be half of that of

VCELL

. To reduce current consumption from

the battery, the CVON output may used to connect the
divider to the cells only during measurement period.
CVON is high impedance for 250ms (12.5% duty cycle)
when the cells are measured, and driven low otherwise.
See Table 1.

Current

The SRC input of the bq2060 measures battery charge
and discharge current.

The SRC ADC input converts

the current signal from the series sense resistor and
stores the result in Current(). The full-scale input range
to SBC is limited to

250mV as shown in Table 2.

bq2060

Temperature

The TS input of the bq2060 in conjunction with an NTC
thermistor measures the battery temperature as shown
in Figure 1. The bq2060 reports temperature in Tem-
perature().

THON may be used to connect the bias

source to the thermistor when the bq2060 samples the
TS input. THON is high impedance for 60ms when the
temperature is measured, and driven low otherwise.

Gas Gauge Operation

General

The operational overview in Figure 2 illustrates the gas
gauge operation of the bq2060.

Table 3 describes the

bq2060 registers.

The bq2060 accumulates a measure of charge and dis-
charge currents and estimates self-discharge of the bat-
tery. The bq2060 compensates the charge current mea-
surement for temperature and state-of-charge of the
battery. The bq2060 also adjusts the self-discharge esti-
mation based on temperature.

The main counter RemainingCapacity() (RM) represents
the available capacity or energy in the battery at any

Sense Resistor (

)

Full-Scale Input

(A)

0.02

±12.5

0.03

8.3

0.05

5.0

0.10

2.5

Table 2. SRC Input Range

Figure 2. bq2060 Operational Overview

bq2060

Voltage Input

Voltage Division

Ratio

Full-Scale Input

(V)

VCELL

20.0

VCELL

20.0

VCELL

10.0

VCELL

10.0

Table 1. Example VCELL

VCELL

Divider

and Input Range

given time.

The bq2060 adjusts RM for charge,

self-discharge, and leakage compensation factors. The
information in the RM register is accessible through the
communications ports and is also represented through
the LED display.

The FullChargeCapacity() (FCC) register represents the
last measured full discharge of the battery. It is used as
the battery's full-charge reference for relative capacity
indication. The bq2060 updates FCC when the battery
undergoes a qualified discharge from nearly full to a low
battery level. FCC is accessible through the serial com-
munications ports.

The Discharge Count Register (DCR) is a non-accessible
register that only tracks discharge of the battery. The
bq2060 uses the DCR register to update the FCC regis-
ter if the battery undergoes a qualified discharge from
nearly full to a low battery level.

In this way, the

bq2060 learns the true discharge capacity of the battery
under system use conditions.

Main Gas Gauge Registers

RemainingCapacity() (RM)

RM represents the remaining capacity in the battery.
The bq2060 computes RM in either mAh or 10mWh de-
pending on the selected mode.

On initialization, the bq2060 sets RM to 0. RM counts
up during charge to a maximum value of FCC and down
during discharge and self-discharge to 0. In addition to
charge and self-discharge compensation, the bq2060 cal-
ibrates RM at three low-battery-voltage thresholds,
EDV2, EDV1, and EDV0 and three programmable
midrange thresholds VOC25, VOC50, and VOC75. This
provides a voltage-based calibration to the RM counter.

DesignCapacity() (DC)

The DC is the user-specified battery full capacity. It is
calculated from Pack Capacity EE 0x3a0x3b and is rep-
resented in mAh or 10mWh. It also represents the
full-battery reference for the absolute display mode.

FullChargeCapacity() (FCC)

FCC is the last measured discharge capacity of the bat-
tery. It is represented in either mAh or 10mWh depend-
ing on the selected mode. On initialization, the bq2060
sets FCC to the value stored in Last Measured Dis-
charge EE 0x380x39. During subsequent discharges,
the bq2060 updates FCC with the last measured dis-
charge capacity of the battery. The last measured dis-
charge of the battery is based on the value in the DCR
register after a qualified discharge occurs.

Once up-

dated, the bq2060 writes the new FCC value to
EEPROM in mAh to Last Measured Discharge.

FCC

represents the full battery reference for the relative dis-
play mode and relative state of charge calculations.

Discharge Count Register (DCR)

The DCR register counts up during discharge, independ-
ent of RM. DCR can continue to count even after RM has
counted down to 0. Prior to RM = 0, discharge activity,
light discharge estimation and self-discharge increment
DCR. After RM = 0, only discharge activity increments
DCR. The bq2060 initializes DCR to FCC RM when
RM is within twice the programmed value in Near Full
EE 0x55. The DCR initial value of FCC RM is reduced
by FCC/128 if SC = 0 (bit 2 in Control Mode) and is not
reduced if SC = 1. DCR stops counting when the battery
voltage reaches the EDV2 threshold on discharge.

Capacity Learning (FCC Update) and Qualified
Discharge

The bq2060 updates FCC with an amount based on the
value in DCR if a qualified discharge occurs. The new
value for FCC equals the DCR value plus the program-
mable nearly full and low battery levels, according to
the following equation:

FCC(new)

DCR(final)

DCR(initial)

measured dischar

ge to EDV2

(FCC

´ BatteryLow%)

(1)

where

BatteryLow%

(value stored in EE 0x54)

2 56

A qualified discharge occurs if the battery discharges
from RM

FCC - Near Full * 2 to the EDV2 voltage

threshold with the following conditions:

No valid charge activity occurs during the discharge
period.

A valid charge is defined as an input of

10mAh into the battery.

No more than 256mAh of self-discharge and/or light
discharge estimation occurs during the discharge
period.

The temperature does not drop below 5

C during the

discharge period.

The battery voltage reaches the EDV2 threshold
during the discharge period and the voltage was less
than the EDV2 threshold minus 256mV when the
bq2060 detected EDV2.

No midrange voltage correction occurs during the
discharge period.

FCC cannot be reduced by more than 256mAh or in-
creased by more than 512mAh during any single update
cycle.

The bq2060 saves the new FCC value to the

EEPROM within 4s of being updated.

bq2060

bq2060

Function

Command Code

SMBus

Access

Units

SMBus

HDQ16

ManufacturerAccess

0x00

read/write

n/a

RemainingCapacityAlarm

0x01

read/write

mAh, 10mWh

RemainingTimeAlarm

0x02

read/write

minutes

BatteryMode

0x03

read/write

n/a

AtRate

0x04

read/write

mA, 10mW

AtRateTimeToFull

0x05

read

minutes

AtRateTimeToEmpty

0x06

read

minutes

AtRateOK

0x07

read

Boolean

Temperature

0x08

read

0.1°K

Voltage

0x09

read

Current

0x0a

read

AverageCurrent

0x0b

read

MaxError

0x0c

read

percent

RelativeStateOfCharge

0x0d

read

percent

AbsoluteStateOfCharge

0x0e

read

percent

RemainingCapacity

0x0f

read

mAh, 10mWh

FullChargeCapacity

0x10

read

mAh, 10mWh

RunTimeToEmpty

0x11

read

minutes

AverageTimeToEmpty

0x12

read

minutes

AverageTimeToFull

0x13

read

minutes

ChargingCurrent

0x14

read

ChargingVoltage

0x15

read

Battery Status

0x16

read

n/a

CycleCount

0x17

read

cycles

DesignCapacity

0x18

read

mAh, 10mWh

DesignVoltage

0x19

read

SpecificationInfo

0x1a

read

n/a

ManufactureDate

0x1b

read

n/a

SerialNumber

0x1c

read

integer

Reserved

0x1d0x1f

0x1d - 0x1f

ManufacturerName

0x20

0x200x25

read

string

DeviceName

0x21

0x280x2b

read

string

DeviceChemistry

0x22

0x300x32

read

string

ManufacturerData

0x23

0x380x3b

read

string

Pack Status

0x2f (LSB)

read/write

n/a

Pack Configuration

0x2f (MSB)

read/write

n/a

VCELL4

0x3c

read/write

VCELL3

0x3d

read/write

VCELL2

0x3e

read/write

VCELL1

0x3f

read/write

Table 3. bq2060 Register Functions

End-of-Discharge Thresholds and Capacity Cor-
rection

The bq2060 monitors the battery for three low-voltage
thresholds, EDV0, EDV1, and EDV2. The EDV thresh-
olds are programmed in EDVF/EDV0 EE 0x720x73,
EMF/EDV1 EE 0x740x75, and EDV C1/C0 Fac-
tor/EDV2 EE 0x780x79. If the CEDV bit in Pack Con-
figuration is set, automatic EDV compensation is en-
abled and the bq2060 computes the EDV0, EDV1, and
EDV2 thresholds based on the values in EE 0x720x7d,
0x06, and the battery's current discharge rate, tempera-
ture, capacity, and cycle count. The bq2060 disables
EDV detection if Current() exceeds the Overload Current
threshold programmed in EE 0x46 - EE 0x47.

The

bq2060 resumes EDV threshold detection after Cur-
rent() drops below the overload current threshold. Any
EDV threshold detected will be reset after 10mAh of
charge are applied.

The bq2060 uses the thresholds to apply voltage-based
corrections to the RM register according to Table 4.

The bq2060 adjusts RM as it detects each threshold. If
the voltage threshold is reached before the correspond-
ing capacity on discharge, the bq2060 reduces RM to the
appropriate amount as shown in Table 4. If RM reaches
the capacity level before the voltage threshold is reached
on discharge, the bq2060 prevents RM from decreasing
until the battery voltage reaches the corresponding
threshold.

Self-Discharge

The bq2060 estimates the self-discharge of the battery
to maintain an accurate measure of the battery capacity
during periods of

inactivity. The algorithm for

self-discharge estimation takes a programmed estimate
for the expected self-discharge rate at 25

C stored in

EEPROM and makes a fixed reduction to RM of an
amount equal to RemainingCapacity()/256. The bq2060
makes the fixed reduction at a varying time interval
that is adjusted to achieve the desired self-discharge
rate. This method maintains a constant granularity of
0.39% for each self-discharge adjustment, which may be
performed multiple times per day, instead of once per
day with a potentially large reduction.

The self-discharge estimation rate for 25

C is doubled

for each 10 degrees above 25

C or halved for each 10 de-

grees below 25

C. The following table shows the relation

of the self-discharge estimation at a given temperature
to the rate programmed for 25

C (Y% per day):

Temperature ( C)

Self-Discharge Rate

Temp

1
4

Y% per day

Temp

1
2

Y% per day

Temp

Y% per day

Temp

2Y% per day

Temp

4Y% per day

Temp

8Y% per day

Temp

16Y% per day

Temp

32Y% per day

The interval at which RM is reduced is given by the fol-
lowing equation, where n is the appropriate factor of 2
(n =

1
4

1
2

, 1, 2, . . . ):

(2)

Self Disch

e Update Time

n Y

per day

· ·

arg

640 13500

256

( %

)

seconds

The timer that keeps track of the self-discharge update
time is halted whenever charge activity is detected. The
timer is reset to zero if the bq2060 reaches the
RemainingCapacity()=FullChargeCapacity() condition
while charging.

Example: If T = 35

C (n = 2) and programmed

self-discharge rate Y is 2.5 (2.5% per day at 25

C), the

bq2060 reduces RM by RM/256 (0.39%) every

(3)

640 13500

256

6750

· ·

per day

( %

)

econds

bq2060

Threshold

State of Charge in RM

EDV0

EDV1

EDV2

Battery Low %

Table 4. State of Charge Based

on Low Battery Voltage

Figure 3. Self-Discharge at 2.5%/Day @25C

This means that a 0.39% reduction of RM will be made
12.8 times per day to achieve the desired 5% per day re-
duction at 35

Figure 3 illustrates how the self-discharge estimate al-
gorithm adjusts RemainingCapacity() vs. temperature.

L i g h t D i s c h a r g e o r S u s p e n d C u r r e n t
Compensation

The bq2060 can be configured in two ways to compen-
sate for small discharge currents that produce a signal
below the digital filter. First, the bq2060 can decrement
RM and DCR at a rate determined by the value stored
in Light Discharge Current EE 0x2b when it detects no
discharge activity and the SMBC and SMBD lines are
high. Light Discharge Current has a range of 44

A to

11.2mA.

Alternatively, the bq2060 can be configured to disable
the digital filter for discharge when the SMBC and
SMBD lines are high. In this way, the digital filter will
not mask the leakage current signal. The bq2060 is con-
figured in this mode by setting the NDF bit in Control
Mode.

Midrange Capacity Corrections

The bq2060 applies midrange capacity corrections when
the VCOR bit is set in Pack Configuration. The bq2060
adjusts RM to the associated percentage at three differ-
ent voltage levels VOC25, VOC50, and VOC75. The VOC
values represent the open circuit battery voltage at
which RM corresponds to the associated state of charge
for each threshold.

Threshold

Associated State of Charge

VOC25

25%

VOC50

50%

VOC75

75%

For the midrange corrections to occur, the temperature
must be in the range of 19

C to 31

C inclusive and the

Current() and AverageCurrent() must both be between
64mA and 0. The bq2060 makes midrange corrections
as shown in Table 5.

Charge Control

Charging Voltage and Current Broadcasts

The bq2060 supports SBS charge control by broadcasting
the ChargingCurrent() and ChargingVoltage() to the
Smart Charger address. The bq2060 broadcasts the re-
quests every 10s. The bq2060 updates the values used in
the charging current and voltage broadcasts based on the
battery's state of charge, voltage, and temperature. The
fast-charge rate is programmed in Fast-Charging Current
EE 0x1a - 0x1b while the charge voltage is programmed in
Charging Voltage EE 0x0a-0x0b.

The bq2060 internal charge control is compatible with
popular rechargeable chemistries.

The primary

charge-termination techniques include a change in tem-
perature over a change in time (

t) and current

taper, for nickel-based and Li-Ion chemistries, respec-
tively.

The bq2060 also provides pre-charge qualifica-

tion and a number of safety charge suspensions based
on current, voltage, temperature, and state of charge.

Alarm Broadcasts to Smart Charger and Host

If any of the bits 815 in BatteryStatus() is set, the
bq2060 broadcasts an AlarmWarning() message to the
Host address. If any of the bits 1215 in BatteryStatus()
are set, the bq2060 also sends an AlarmWarning() mes-
sage to the Smart Charger address. The bq2060 repeats
the AlarmWarning() message every 10s until the bits are
cleared.

Pre-Charge Qualification

The bq2060 sets ChargingCurrent() to the pre-charge
rate as programmed in Pre-Charge Current EE
0x1e-0x1f under the following conditions:

Condition

Result

Voltage()

VOC75 and RelativeStateOfCharge()

63%

RelativeStateOfCharge()

75%

< VOC75 and RelativeStateOfCharge()

87%

RelativeStateOfCharge()

75%

VOC50 and RelativeStateOfCharge()

38%

RelativeStateOfCharge()

50%

<VOC50 and RelativeStateOfCharge()

62%

RelativeStateOfCharge()

50%

VOC25 and RelativeStateOfCharge()

13%

RelativeStateOfCharge()

25%

< VOC25 and RelativeStateOfCharge()

37%

RelativeStateOfCharge()

25%

Table 5. Midrange Corrections

bq2060

Voltage: The bq2060 requests the pre-charge charge
rate when Voltage() drops below the EDV0 threshold
(compensated or fixed EDVs). Once requested, a
pre-charge rate remains until Voltage() increases
above

the

EDVF

threshold.

The

bq2060

also

broadcasts the pre-charge value immediately after a
device reset until Voltage() is above the EDVF
threshold.

This

threshold

programmed

EDVF/EDV0 EE 0x72-0x73.

Temperature: The bq2060 requests the pre-charge
rate when Temperature() is between 0°C and 5°C.
Temperature() must rise above 5°C before the bq2060
requests the fast-charge rate.

Charge Suspension

The bq2060 may temporarily suspend charge if it de-
tects a charging fault. A charging fault includes the fol-
lowing conditions.

Overcurrent:

An overcurrent condition exists when

the bq2060 measures the charge current to be more than
the Overcurrent Margin above the ChargingCurrent().
Overcurrent Margin is programmed in EE 0x49. On
detecting an overcurrent condition, the bq2060 sets the
ChargingCurrent()

zero

and

sets

the

TERMINATE_CHARGE_ALARM

bit

Battery

Status(). The overcurrent condition and TERMINATE_
CHARGE_ALARM are cleared when the measured
current drops below the ChargingCurrent plus the
Overcurrent Margin.

Overvoltage: An overvoltage condition exists when the
bq2060 measures the battery voltage to be more than
the Overvoltage Margin above the ChargingVoltage() or
a Li-Ion cell voltage has exceeded the overvoltage limit
programmed in Cell Under-/Overoltage. Overvoltage
Margin is programmed in EE 0x48 and Cell Under/Over
Voltage in EE 0x4a (least significant nibble). On
detecting an overvoltage condition, the bq2060 sets the
ChargingCurrent()

zero

and

sets

the

TERMINATE_CHARGE_ALARM bit in BatteryStatus().
The

bq2060

clears

the

TERMINATE_

CHARGE_ALARM bit when it detects that the battery
is no longer being charged (DISCHARGING bit set in
BatteryStatus()). The bq2060 continues to broadcast zero
charging current until the overvoltage condition is
cleared. The overvoltage condition is cleared when the
measured

battery

voltage

drops

below

the

ChargingVoltage() plus the Overvoltage Margin or when
the CVOV bit is reset.

Over-Temperature: An over-temperature condition
exists when Temperature() is greater than or equal to
the Max T value programmed in EE 0x45 (most
significant nibble). On detecting an over-temperature
condition, the bq2060 sets the ChargingCurrent() to
zero

and

sets

the

OVER_TEMP_ALARM

and

TERMINATE_CHARGE_

ALARM

bit

BatteryStatus() and the CVOV bit in Pack Status.

The over-temperature condition is cleared when
Temperature() is equal to or below (Max T 5

C).

Overcharge: An overcharge condition exists if the
battery

charged

than

the

Maxmum

Overcharge value after RM = FCC. Maximum
Overcharge is programmed in EE 0x2e0x2f. On
detecting an overcharge condition, the bq2060 sets
the

ChargingCurrent()

zero

and

sets

the

OVER_CHARGED_ALARM, TERMINATE_CHARGE_
ALARM,

and

FULLY_CHARGED

bits

BatteryStatus().

The

bq2060

clears

the

OVER_

CHARGED_ALARM

and

TERMINATE_CHARGE_

ALARM when it detects that the battery is no longer
being charged. The FULLY_CHARGED bit remains set
and the bq2060 continues to broadcast zero charging
current until RelativeStateOfCharge() is less than
Fully Charged Clear% programmed in EE 0x4c.The
counter used to track overcharge capacity is reset
with 2mAh of discharge.

Under-Temperature:

under-temperature

condition exists if Temperature() < 0°C. On detecting
an under temperature condition, the bq2060 sets
ChargingCurrent()

zero.

The

bq2060

sets

ChargingCurrent() to the appropriate pre-charge rate
or fast-charge rate when Temperature()

0°C.

Primary Charge Termination

T h e b q 2 0 6 0 t e r m i n a t e s c h a r g e i f i t d e t e c t s a
charge-termination condition.

A charge-termination

condition includes the following.

t: For

t, the bq2060 detects a change in

temperature over many seconds. The

t setting

is programmable in both the temperature step,
DeltaT (1.6

C - 4.6

C), and the time step, DeltaT

Time (20s-320s).

Typical settings for 1

C/minute

include 2

C/120s and 3

C/180s.

Longer times are

required for increased slope resolution. The DeltaT
value is programmed in EE 0x45 (least significant
nibble) and the Delta T Time in EE 0x4e.

In addition to the

t timer, a hold-off timer starts

when the battery is being charged at more than
255mA and the temperature is above 25

C. Until this

timer expires,

t detection is suspended. If

Current() drops below 256mA or Temperature() below
25

C, the hold-off timer resets and restarts only when

the current and temperature conditions are met again.
The hold-off timer is programmable (20s 320s) with
Holdoff Time value in EE 0x4f.

Current Taper: For current taper, ChargingVoltage()
must be set to the pack voltage desired during the
constant-voltage phase of charging. The bq2060 detects a
current taper termination when the pack voltage is
greater than the voltage determined by Current Taper
Qual Voltage in EE 0x4f and the charging current is
below

threshold

determined

Current

Taper

bq2060

Threshold in EE 0x4e, for at least 40s. The bq2060 uses
the

VFC

measure

current

for

current

taper

termination. The current polarity must remain positive as
measured by the VFC during this time.

Once the bq2060 detects a primary charge termination,
the bq2060 sets the TERMINATE_CHARGE_ALARM
and FULLY_CHARGED bits in BatteryStatus(), and
sets the ChargingCurrent() to the maintenance charge
rate as programmed in Maintenance Charging Current
EE 0x1c0x1d. On termination, the bq2060 also sets
RM to a programmed percentage of FCC, provided that
R e l a t i v e S t a t e O f C h a r g e ( ) i s b e l o w t h e d e s i r e d
percentage of FCC and the CSYNC bit in Pack Configu-
ration EE 0x3f is set. If the CSYNC bit is not set and
RelativeStateOfCharge() is less than the programmed
p e r c e n t a g e

o f

F C C ,

t h e

b q 2 0 6 0

c l e a r s

t h e

FULLY_CHARGED bit in BatteryStatus().

The pro-

grammed percentage of FCC, Fast Charge Termination
% , i s s e t i n E E 0 x 4 b . T h e b q 2 0 6 0 c l e a r s t h e
FULLY_CHARGED bit when RelativeStateOfCharge()
is less than the programmed Fully Charged Clear %.
The bq2060 broadcasts the fast-charge rate when the
FULLY_CHARGED bit is cleared and voltage and tem-
perature permit. The bq2060 clears the TERMI-
NATE_CHARGE_ALARM when it no longer detects
that the battery is being charged or it no longer detects
the termination condition. See Table 6 for a summary
of BatteryStatus() alarm and status bit operation.

Display Port

General

The display port drives a 4 or 5 LED bar-graph display.
The display is activated by a logic signal on the DISP in-
put. The bq2060 can display RM in either a relative or
absolute mode with each LED representing a percentage
of the full-battery reference.

In relative mode, the

bq2060 uses FCC as the full-battery reference; in abso-
lute mode, it uses DC.

The DMODE bit in Pack Configuration programs the
bq2060 for the absolute or relative display mode. The
LED bit in Control Mode programs the 4 or 5 LED op-
tion. A 5th LED can be used with the 4 LED display op-
tion to show when the battery capacity is

to 100%.

Activation

The display may be activated at any time by a
high-to-low transition on the DISP input. This is usually
accomplished with a pullup resistor and a pushbutton
switch.

Detection of the transition activates the dis-

play and starts a four-second display timer. The timer
expires and turns off the display whether DISP was
brought low momentarily or held low indefinitely. Reac-
tivation of the display requires that the DISP input re-
turn to a logic-high state and then transition low again.
The second high-to-low transition must occur after the

display timer expires. The bq2060 requires the DISP in-
put to remain stable for a minimum of 250ms to detect
the logic state.

If the EDV0 bit is set, the bq2060 disables the LED dis-
play. The display is also disabled during a VFC calibra-
tion and should be turned off before entering low-power
storage mode.

Display Modes

In relative mode, each LED output represents 20% or
25% of the RelativeStateOfCharge() value. In absolute
mode, each LED output represents 20% or 25% of the
AbsoluteStateOfCharge() value. Table 7 shows the dis-
play operation.

In either mode, the bq2060 blinks the LED display if
R e m a i n i n g C a p a c i t y ( ) i s l e s s t h a n R e m a i n i n g
CapacityAlarm(). The display is disabled if EDV0 = 1.

Secondary Protection for Li-Ion

Undervoltage and overvoltage thresholds may be pro-
grammed in the byte value Cell Under/Over Voltage EE
0x4a to set a secondary level of protection for Lithium
Ion cells. The bq2060 checks individual cell voltages for
undervoltage and overvoltage conditions.

The bq2060

displays the results in the Pack Status register and con-
trols the state of the FET control outputs CFC and DFC.
If any cell voltage is less than the V

threshold, the

bq2060 sets the CVUV bit in Pack Status and pulls the
DFC pin to a logic low. If any cell voltage is greater than
the V

threshold, the bq2060 sets the CVOV bit in Pack

Status and pulls the CFC pin to a logic low.

Low-Power Storage Mode

The bq2060 enters low-power mode 5 8s after receiving
the Enable Low-Power command. In this mode the
bq2060 consumes less than 10

A. A rising edge on

SMBC, SMBD, or HDQ16 restores the bq2060 to the full
operating mode. The bq2060 does not perform any gas
gauge functions during low-power storage mode.

Device Reset

The bq2060 can be reset with commands over the
HDQ16 or SMBus. Upon reset, the bq2060 initializes its
internal registers with the information contained in the
configuration EEPROM. The following command se-
quence initiates a full bq2060 reset:

Write 0x4f to 0xff5a

Write 0x7d to 0x0000

Write 0x7d to 0x0080

bq2060

Battery State

Conditions

CC() State and

BatteryStatus Bits Set

CC() = Fast or Pre-charge Current

and/or Bits Cleared

Overcurrent

C()

CC() + Overcurrent

Margin

CC() = 0, TCA = 1

C() < CC() + Overcurrent Margin

Overvoltage

V()

() +

Overvoltage

Margin

VCELL1, 2, 3, or 4 > Cell

Over Voltage

TCA = 1

DISCHARGING = 1

CC() = 0, CVOV = 1

V() < CV() + Overvoltage Margin

Li-Ion cell voltage

Cell Over Voltage

Overtemperature

T()

Max T

CC() = 0, OTA = 1,

TCA = 1, CVOV = 1

T()

Max T - 5

C or T()

43°

Overcharge

Capacity added after

RM() = FCC()

Maximum Overcharge

CC() = 0, FC = 1

RSOC() < Fully Charged Cleared %

OCA = 1, TCA = 1

DISCHARGING = 1

Undertemperature

T() < 0

CC() = 0

() <

C, CC() = Pre-Charge

Current

T()

5°

C, CC() = Fast-Charging Current

Fast charge

termination

t or Current Taper

CC() = Maintenance

Charging Current,

FC = 1

RSOC() < Fully Charged Cleared %

TCA = 1

DISCHARGING = 1 or termination

condition is no longer valid.

Fully discharged

V()

EDV2

FD = 1

RSOC() > 20%

Overdischarged

V()

EDV0

TDA = 1

V() > EDV0

VCELL1, 2, 3 or 4 < Cell

Under Voltage

TDA = 1, CVUV = 1

VCELL1, 2, 3, or 4

Cell Under Voltage

Low capacity

RM() < RCA()

RCA = 1

RM()

RCA()

Low run-time

ATTE() < RTA()

RTA = 1

ATTE()

RTA()

Note:

C() = Current(), CV() = ChargingVoltage(), CC() = ChargingCurrent(), V() = Voltage(), T() = Tempera-

ture(), TCA = TERMINATE_CHARGE_ALARM, OTA = OVER_TEMPERATURE_ALARM,
OCA = OVER_CHARGED_ALARM, TDA = TERMINATE_DISCHARGE_ALARM, FC =
FULLY_CHARGED,
FD = FULLY_DISCHARGED, RSOC() = RelativeStateOfCharge(). RM() = RemainingCapacity(),
RCA = REMAINING_CAPACITY_ALARM, RTA = REMAINING_TIME_ALARM,
ATTE() = AverageTimeToEmpty(), RTA() = RemainingTimeAlarm(), RCA() = RemainingCapacityAlarm(),
FCC() = FullChargeCapacity.

Table 6. Alarm and Status Bit Summary

bq2060

Communication

The bq2060 includes two types of communication ports:
SMBus and HDQ16. The SMBus interface is a 2-wire
bidirectional protocol using the SMBC (clock) and SMBD
( d a t a ) p i n s . T h e H D Q 1 6 i n t e r f a c e i s a 1 - w i r e
bidirectional protocol using the HDQ16 pin. All three
communication lines are isolated from V

and may be

pulled-up higher than V

. Also, the bq2060 will not

pull these lines low if V

to the part is zero . HDQ16

should be pulled down with a 100K

resistor if not used.

The communication ports allow a host controller, an
SMBus compatible device, or other processor to access
the memory registers of the bq2060. In this way a sys-
tem can efficiently monitor and manage the battery.

SMBus

The SMBus interface is a command-based protocol. A
processor acting as the bus master initiates communica-
tion to the bq2060 by generating a START condition. A
START condition consists of a high-to-low transition of
the SMBD line while the SMBC is high. The processor
then sends the bq2060 device address of 0001011 (bits
71) plus a R/W bit (bit 0) followed by an SMBus com-
mand code. The R/W bit and the command code instruct
the bq2060 to either store the forthcoming data to a reg-
ister specified by the SMBus command code or output
the data from the specified register. The processor com-
pletes the access with a STOP condition. A STOP condi-
tion consists of a low-to-high transition of the SMBD
line while the SMBC is high. With SMBus, the most sig-
nificant bit of a data byte is transmitted first.

In some instances, the bq2060 acts as the bus master.
This occurs when the bq2060 broadcasts charging re-
quirements and alarm conditions to device addresses
0x12 (SBS Smart Charger) and 0x10 (SBS Host Control-
ler.)

SMBus Protocol

The bq2060 supports the following SMBus protocols:

Read Word

Write Word

Read Block

A processor acting as the bus master uses the three pro-
tocols to communicate with the bq2060. The bq2060 act-
ing as the bus master uses the Write Word protocol.

The SMBD and SMBC pins are open drain and require
external pullup resistors.

SMBus Packet Error Checking

The bq2060 supports Packet Error Checking as a mecha-
nism to confirm proper communication between it and
another SMBus device. Packet Error Checking requires
that both the transmitter and receiver calculate a Packet
Error Code (PEC) for each communication message. The
device that supplies the last byte in the communication
message appends the PEC to the message. The receiver
compares the transmitted PEC to its PEC result to deter-
mine if there is a communication error.

PEC Protocol

The bq2060 can receive or transmit data with or without
PEC.

Figure 4 shows the communication protocol for

the Read Word, Write Word, and Read Block messages
without PEC. Figure 5 includes PEC.

In the Write Word protocol, the bq2060 receives the PEC
after the last byte of data from the host. If the host does
not support PEC, the last byte of data is followed by a
STOP condition. After receipt of the PEC, the bq2060
compares the value to its calculation. If the PEC is cor-
rect, the bq2060 responds with an ACKNOWLEDGE. If
it is not correct, the bq2060 responds with a NOT AC-
KNOWLEDGE and sets an error code.

bq2060

Condition

Relative or

Absolute

StateOfCharge()

5 LED Display Option

LED1

LED2 LED3 LED4

LED5

EDV0 = 1

OFF

20%

OFF

20%, <40%

OFF

40%, <

60%

OFF

60%, <

80%

OFF

80%

Table 7A. Display Mode

Condition

Relative or

Absolute

StateOfCharge()

4 LED Display Option

LED1

LED2

LED3

LED4

EDV0 = 1

OFF

25%

OFF

25%, <

50%

OFF

50%, <

75%

OFF

75%

Table 7B. Display Mode

FG2060HCP.eps

Battery Address

0001011

Command Code

Data byte low

Data byte high

Battery Address

0001011

Command Code

Battery Address

Data byte low

Data byte high

Battery Address

0001011

Command Code

Battery Address

Byte Count =N

Data byte 1

Data byte 2

Data byte N

bq2060

Host Processor

Block Read

Read Word

Write Word

A ACKNOWLEDGE
A NOT ACKNOWLEDGE
S START
P STOP

Figure 4. SMBus Communication Protocol without PEC

FG2060PEC.eps

Battery Address

0001011

Command Code

Data byte low

PEC

Data byte high

Battery Address

0001011

Command Code

Battery Address

Data byte low

Data byte high

PEC

Battery Address

0001011

Command Code

Battery Address

Byte Count =N

Data byte 1

Data byte 2

Data byte N

PEC

bq2060

Host Processor

Block Read

Read Word

Write Word

A ACKNOWLEDGE
A NOT ACKNOWLEDGE
S START
P STOP

Figure 5. SMBus Communication Protocol with PEC

bq2060

In the Read Word and Block Read, the host generates an
ACKNOWLEDGE after the last byte of data sent by the
bq2060. The bq2060 then sends the PEC and the host
acting as a master-receiver generates a NOT AC-
KNOWLEDGE and a STOP condition.

PEC Calculation

The basis of the PEC calculation is an 8-bit Cyclic Re-
dundancy Check (CRC-8) based on the polynomial C(X)
= X

+ X

+ 1. The PEC calculation includes all

bytes in the transmission, including address, command,
and data.

The PEC calculation does not include AC-

KNOWLEDGE, NOT ACKNOWLEDGE, START, STOP,
and Repeated START bits.

For example, the host requests RemainingCapacity()
from the bq2060. This includes the host following the
Read Word protocol.

The bq2060 calculates the PEC

based on the following 5 bytes of data, assuming the re-
maining capacity of the battery is 1001mAh.

Battery Address with R/W = 0: 0x16

Command Code for RemainingCapacity(): 0x0f

Battery Address with R/W = 1: 0x17

RemainingCapacity(): 0x03e9

For 0x160f17e903, the bq2060 transmits a PEC of 0xe8
to the host.

PEC Enable in Master Mode

PEC for master mode broadcasts to the charger, host, or
both can be enabled/disabled with the combination of
the bits HPE and CPE in Control Mode.

SMBus On and Off State

The bq2060 detects whether the SMBus enters the Off
State" by monitoring the SMBC and SMBD lines. When
both signals are continually low for at least 2.5s, the
bq2060 detects the Off State. When the SMBC and
SMBD lines go high, the bq2060 detects the On State
and can begin communication within 1ms. One-M

pulldown resistors on SMBC and SMBD

are recom-

mended for reliable Off State detection.

HDQ16

The HDQ16 interface is a command-based protocol. (See
Figure 6.) A processor sends the command code to the
bq2060. The 8-bit command code consists of two fields,
the 7-bit HDQ16 command code (bits 06) and the 1-bit
R/W field. The R/W field directs the bq2060 either to

Store the next 16 bits of data to a specified register or

Output 16 bits of data from the specified register

With HDQ16, the least significant bit of a data byte
(command) or word (data) is transmitted first.

A bit transmission consists of three distinct sections. The
first section starts the transmission by either the host or
the bq2060 taking the HDQ16 pin to a logic-low state for
a period t

S T R H ; B

. The next section is the actual

data-transmission, where the data bit is valid by the
time, t

DSU;B

after the negative edge used to start commu-

nication. The data bit is held for a period t

DH;DV

to allow

the host processor or bq2060 to sample the data bit.

The final section is used to stop the transmission by re-
turning the HDQ16 pin to a logic-high state by at least
the time t

SSU;B

after the negative edge used to start

communication. The final logic-high state should be un-
til a period t

CYCH;B

to allow time to ensure that the bit

transmission was stopped properly.

If a communication error occurs (e.g., t

CYCB

> 250

s),

the host sends the bq2060 a BREAK to reinitiate the se-
rial interface. The bq2060 detects a BREAK when the
HDQ16 pin is in a logic-low state for a time t

greater. The HDQ16 pin is then returned to its normal
ready-high logic state for a time t

. The bq2060 is then

ready to receive a command from the host processor.

The HDQ16 pin is open drain and requires an external
pullup resistor.

Command Codes

The SMBus Command Codes are in ( ), the HDQ16 in [ ].
Temperature(), Voltage(), Current(), and AverageCurrent(),
performance specifications are at regulated V

)

and a temperature of 070

ManufacturerAccess() (0x00); [0x000x01]

Description:
This function provides writable command codes to con-
trol the bq2060 during normal operation and pack man-
ufacture. These commands can be ignored if sent within
one second after a device reset. The following list of com-
mands are available.

0x0618 Enable Low-Power Storage Mode: Activates
the low-power storage mode. The bq2060 enters the
storage mode after a 58s delay. The bq2060 accepts
other commands to ManufacturerAccess() during the
delay before entering low-power storage mode. The
LEDs must be off before entering the low-power storage
mode as the display state remains unchanged. During
the delay following the low-power storage command, a
VFC Calibration command may be issued.

The bq2060 clears the ManufacturerAccess() command
within 900ms of acknowledging the Enable Low-Power
Storage command. The VFC Calibration command must
be sent 9001600ms after SMBus acknowledgment of
the Enable Low-Power Storage command. In this case,
the bq2060 delays entering storage mode until the cali-
bration process completes and the bq2060 stores the
new calibration values in EEPROM.

bq2060

0x062b SEAL Command: Instructs the bq2060 to re-
strict access to those functions listed in Table 3. Note:
The SEAL Command does not change the state of the
SEAL bit in Pack Configuration in EEPROM. The
b q 2 0 6 0 c o m p l e t e s t h e s e a l f u n c t i o n a n d c l e a r s
ManufacturerAccess() within 900ms of acknowledging
the command.

0x064d

Charge Synchronization:

Instructs the

bq2060 to update RM to a percentage of FCC as defined
in Fast Charge Termination %. The bq2060 updates RM
and clears ManufacturerAccess() within 900ms of ac-
knowledging the command.

0x0653 Enable VFC Calibration: Instructs the un-
sealed bq2060 to begin VFC calibration. With this com-
mand the bq2060 deselects the SR

and SR

inputs and

calibrates for IC offset only. It is best to avoid charge or
discharge currents through the sense resistor during
this calibration process.

0x067e

Alternate VFC Calibration:

Instructs the

unsealed bq2060 to begin VFC calibration. With this
command the bq2060 does not deselect the SR

and SR

inputs and calibrates for IC and PCB offset. During
this procedure no charge or discharge currents

During VFC calibration, the bq2060 disables the LED
display and accepts only the Stop VFC Calibration and
the SEAL Command to ManufacturerAccess(). The
bq2060 disregards all other commands. SMBus
communication should be kept to a minimum during
VFC calibration to reduce the noise level and allow a
more accurate calibration.
Once started, the VFC calibration procedure completes
automatically. When complete, the bq2060 saves the cal-
ibration values in EEPROM. The calibration normally
takes about 8 to 10 minutes. The calibration time is in-
versely proportional to the bq2060 VFC (and PCB) offset

error. The bq2060 caps the calibration time at one hour
in the event of calibrating zero offset error. The VFC
calibration can be done as the last step in a battery pack
test procedure since the calibration can complete auto-
matically after removal from a test setup.

The bq2060 clears ManufacturerAccess() within 900ms
and starts calibration within 3.2s of acknowledging the
command.

0x0660 Stop VFC Calibration: Instructs the bq2060
to abort a VFC calibration procedure. If aborted, the
bq2060 disables offset correction. The bq2060 stops cali-
bration within 20ms of acknowledging the command.

0x0606

Program EEPROM: Instructs the unsealed

bq2060 to connect the SMBus to the EEPROM I

C bus.

The bq2060 applies power to the EEPROM within 900ms
of acknowledging the command. After issuing the pro-
gram EEPROM command, the bq2060 monitoring func-
tions are disabled until the I

C bus is disconnected. The

bq2060 disconnects the I

C bus when it detects that the

Battery Address 0x16 is sent over the SMBus. The Bat-
tery Address 0x16 to disconnect the I

C bus should not

be sent until 10ms after the last write to the EEPROM.

Example: The following sequence of actions is an exam-
ple of how to use the ManufacturerAccess() commands
in an efficient manner to take a battery pack that has
completed all testing and calibration except for VFC cal-
ibration and to make it ready for shipment in the
SEALED state and in low-power storage mode:

Complete testing and calibration with desired final
values stored in EEPROM. This process includes
setting the SEAL bit in Pack Configuration.
Sending a reset command to the bq2060 during test
ensures that RAM values correspond to the final
EEPROM values

bq2060

Send Host to bq2060

HDQ Command Code

Send Host to bq2060 or

Receive from bq2060

16 bit Data

Break

LSB

Bit0

R/W

MSB

Bit7

TD2060CE.eps

Start-bit

Address-Bit/
Data-Bit

Stop-Bit

tRR

tRSPS

Figure 6. HDQ16 Communication Example

If the initial value of RemainingCapacity() must be
non-zero, the desired value may be written to Com-
mand 0x26 with the pack unsealed. A reset sent af-
ter this step resets RM to zero.

Issue the Enable Low-Power Storage Mode com-
mand.

Within 9001600ms after sending the Enable

Low-Power command, issue the Enable VFC Cali-
bration command. This delays the low-power stor-
age mode until after VFC calibration completion.

Issue the SEAL Command subsequent to the VFC
Calibration command. The bq2060 must receive the
SEAL Command before VFC calibration completes.
The bq2060 resets the OCE bit in Pack Status
when calibration begins and sets the bit when cali-
bration successfully completes.

After VFC calibration completes automatically, the
bq2060 saves the VFC offset cancellation values in
EEPROM and enters the low-power storage mode in
about 20s. In addition, the bq2060 is sealed, allowing ac-
cess as defined in Table 3 only.

Purpose:
The ManufacturerAccess() function provides the system
host access to bq2060 functions that are not defined by
the SBD.

SMBus Protocol: Read or Write Word

Input/Output: Word

RemainingCapacityAlarm() (0x01); [0x01]

Description:
Sets or gets the low-capacity threshold value. Whenever
the RemainingCapacity() falls below the low capacity
value, the bq2060 sends AlarmWarning() messages to
the SMBus Host with the REMAINING_CAPAC-
ITY_ALARM bit set. A low-capacity value of 0 disables
this alarm. The bq2060 initially sets the low-capacity
value to Remaining Capacity Alarm value programmed
in EE 0x04 - 0x05. The low-capacity value remains un-
c h a n g e d

u n t i l

a l t e r e d

b y

t h e

R e m a i n i n g -

CapacityAlarm() function. The low-capacity value may
be expressed in either current (mA) or power (10mWh)
depending on the setting of the BatteryMode()'s CAPAC-
ITY_MODE bit.

Purpose:
The RemainingCapacityAlarm() function can be used by
systems that know how much power they require to save
their operating state. It enables those systems to more
finely control the point at which they transition into sus-
pend or hibernate state. The low-capacity value can be
read to verify the value in use by the bq2060's low capac-
ity alarm.

SMBus Protocol: Read or Write Word

Input/Output: Unsigned integer--value below which
Low Capacity messages are sent.

Battery Modes

CAPACITY_MODE

bit = 0

CAPACITY_MODE

bit = 1

Units

mAh @ C/5

10mWh @ P/5

Range

065,535mAh

065,535 10mWh

Granularity

Not applicable

Accuracy

See RemainingCapacity()

RemainingTimeAlarm() (0x02); [0x02]

Description:
Sets or gets the remaining time alarm value. Whenever
the AverageTimeToEmpty() falls below the remaining time
value, the bq2060 sends AlarmWarning() messages to the
SMBus Host with the REMAINING_TIME_ALARM bit
set. A remaining time value of 0 effectively disables this
alarm. The bq2060 initially sets the remaining time value
to the Remaining Time Alarm value programmed in EE
0x02 - 0x03. The remaining time value remains unchanged
until altered by the RemainingTimeAlarm() function.

Purpose:
The RemainingTimeAlarm() function can be used by
systems that want to adjust when the remaining time
alarm warning is sent. The remaining time value can
be read to verify the value in use by the bq2060's
RemainingTimeAlarm().

SMBus Protocol: Read or Write Word

Input/Output:

Unsigned integer--the point below which remain-
ing time messages are sent.

Units: minutes

Range: 0 to 65,535 minutes

Granularity: Not applicable

Accuracy: see AverageTimeToEmpty()

BatteryMode() (0x03); [0x03]

Description:
This function selects the various battery operational
modes and reports the battery's mode and requests.

Defined modes include

Whether

the

battery's

capacity

information

specified in mAh or 10mWh (CAPACITY_MODE bit)

Whether the ChargingCurrent() and ChargingVoltage()
values are broadcast to the Smart Battery Charger

bq2060

when the bq2060 detects the battery requires charging
(CHARGER_MODE bit)

Whether all broadcasts to the Smart Battery Charger
and Host are disabled

The defined request condition is the battery requesting a
conditioning cycle (RELEARN_FLAG).

Purpose:
The CAPACITY_MODE bit allows power management
systems to best match their electrical characteristics
with those reported by the battery.

For example, a

switching power supply represents a constant power
load, whereas a linear supply is better represented by a
constant current model. The CHARGER_MODE bit al-
lows a SMBus Host or Smart Battery Charger to over-
ride the Smart Battery's desired charging parameters by
d i s a b l i n g t h e b q 2 0 6 0 's b r o a d c a s t s .

T h e R E-

LEARN_FLAG bit allows the bq2060 to request a condi-
tioning cycle.

SMBus Protocol: Read or Write Word

Input/Output:

Unsigned integer --bit mapped-- see below.

Units: not applicable

Range: 01

Granularity: not applicable

Accuracy: not applicable

The BatteryMode() word is divided into two halves, the
most significant bit (bits 815) which is read/write and the

least significant bit (bits 07) which is read only. The
bq2060 forces bits 06 to zero and prohibits writes to bit
7.

Table 8 summarizes the meanings of the individual bits
in the BatteryMode() word and specifies the default val-
ues, where applicable, are noted.

INTERNAL_CHARGE_CONTROLLER bit is not
used by the bq2060.

PRIMARY_BATTERY_SUPPORT bit is not used by
the bq2060.

RELEARN_FLAG bit set indicates that the bq2060 is
requesting a capacity relearn cycle for the battery. The
bq2060 sets the RELEARN_FLAG on a full reset and if
it detects 20 cycle counts without an FCC update. The
bq2060 clears this flag after a learning cycle has been
completed.

CHARGE_CONTROLLER_ENABLED bit is not used
by the bq2060. The bq2060 forces this bit to zero.

PRIMARY_BATTERY bit is not used by the bq2060.
The bq2060 forces this bit to zero.

ALARM_MODE bit is set to disable the bq2060's ability
to master the SMBus and send AlarmWarning() messages
to the SMBus Host and the Smart Battery Charger. When
set, the bq2060 does NOT master the SMBus, and
AlarmWarning() messages are NOT sent to the SMBus
Host and the Smart Battery Charger for a period of no
more than 65s and no less than 45s. When cleared
(default), the Smart Battery sends the AlarmWarning()

bq2060

Battery Mode() Bits

Bits Used

Format

Allowable Values

INTERNAL_CHARGE_CONTROLLER

Read only bit flag

PRIMARY_BATTERY_SUPPORT

Read only bit flag

Reserved

RELEARN_FLAG

Read only bit flag

0--Battery OK

1--Relearn cycle requested

CHARGE_CONTROLLER_ENABLED

R/W bit flag

PRIMARY_BATTERY

R/W bit flag

Reserved

1012

ALARM_MODE

R/W bit flag

0--Enable alarm broadcast (default)

1--Disable alarm broadcast

CHARGER_MODE

R/W bit flag

0--Enable charging broadcast (default)

1--Disable charging broadcast

CAPACITY_MODE

R/W bit flag

0--Report in mA or mAh (default)

1--Report in 10mW or 10mWh

Table 8. Battery Mode Bits and Values

messages to the SMBus Host and the Smart Battery
Charger any time an alarm condition is detected.

The bq2060 polls the ALARM_MODE bit at least
every 150ms. Whenever the ALARM_MODE bit is
set, the bq2060 resets the bit and starts or restarts a
55s (nominal) timer. After the timer expires, the
bq2060 automatically enables alarm broadcasts to
ensure that the accidental deactivation of broadcasts
does not persist. To prevent the bq2060 from
becoming a master on the SMBus, an SMBus host
must therefore continually set this bit at least once
per 50s to keep the bq2060 from broadcasting alarms.

The ALARM_MODE bit defaults to a cleared state
within 130ms after the bq2060 detects the SMBus
Off-State.

The condition of the ALARM-MODE bit does NOT
affect the operation or state of the CHARGER_MODE
bit

which

used

prevent

broadcasts

ChargingCurrent() and ChargingVoltage() to the
Smart Battery Charger.

CHARGER_MODE bit enables or disables the bq2060's
t r a n s m i s s i o n

o f

C h a r g i n g C u r r e n t ( )

a n d

ChargingVoltage() messages to the Smart Battery
Charger.

When set, the bq2060 does NOT transmit

ChargingCurrent() and ChargingVoltage() values to the
Smart Battery Charger.

When cleared, the bq2060

transmits the ChargingCurrent() and ChargingVoltage()
v a l u e s

t o

t h e

S m a r t

B a t t e r y

C h a r g e r.

T h e

CHARGER_MODE bit defaults to a cleared state within
130ms after the bq2060 detects the SMBus Off-State.

CAPACITY_MODE bit indicates if capacity informa-
tion is reported in mA/mAh or 10mW/10mWh.

When

set, the bq2060 reports capacity information in
10mW/10mWh as appropriate.

When cleared, the

bq2060 reports capacity information in mA/mAh as ap-
propriate. The CAPACITY_MODE bit defaults to a
cleared state within 130ms after the bq2060 detects the
SMBus Off-State.

Note 1: The following functions are changed to accept or
return values in mA/mAh or 10mW/10mWh depending
on the CAPACITY_MODE bit:

RemainingCapacityAlarm()

AtRate()

RemainingCapacity()

FullChargeCapacity()

DesignCapacity()

Note 2: The following functions are calculated on the
basis of capacity and may be calculated differently de-
pending on the CAPACITY_MODE bit:

AtRateOK()

AtRateTimeToEmpty()

AtRateTimeToFull()

RunTimeToEmpty()

AverageTimeToEmpty()

AverageTimeToFull()

Remaining Time Alarm()

BatteryStatus()

The bq2060 updates the non-AtRate related register val-
ues within 3s of changing the state of the CAPAC-
ITY_MODE bit. The AtRate() values will be updated af-
ter the next AtRate value is written to the bq2060 (or af-
ter the next 20s scheduled refresh calculation).

AtRate() (0x04); [0x04]

Description:
The AtRate() function is the first half of a two-function
call-set used to set the AtRate value used in calculations
made by the AtRateTimeToFull(), AtRateTime-
ToEmpty(), and AtRateOK() functions.

The AtRate

value may be expressed in either current (mA) or power
(10mW) depending on the setting of the BatteryMode()'s
CAPACITY_MODE bit.

Purpose:
Since the AtRate() function is the first half of a
two-function call-set, it is followed by the second func-
tion of the call-set that calculates and returns a value
based on the AtRate value and the battery's present
state.

A delay of up to 1.3s is required after writing

AtRate() before the bq2060 can acknowledge the re-
quested AtRate function.

When the AtRate() value is positive, the AtRate-
TimeToFull() function returns the predicted time to
full-charge at the AtRate value of charge.

When

the

AtRate()

value

negative,

the

AtRateTimeToEmpty() function returns the predicted
operating time at the AtRate value of discharge.

When the AtRate() value is negative, the AtRateOK()
function returns a Boolean value that predicts the
battery's ability to supply the AtRate value of
additional discharge energy (current or power) for 10
seconds.

The default value for AtRate() is zero.

Writing

AtRate() values over the HDQ16 serial port does NOT
trigger a re-calculation of AtRateTimeToFull(),
AtRateTimeToEmpty(), and AtRateOK() functions.

It is recommended that AtRate() requests should be lim-
ited to one request every 4s.

bq2060

SMBus Protocol: Read or Write Word

Input/Output: Signed integer--charge or discharge;
the AtRate() value is positive for charge, negative for
discharge, and zero for neither (default).

Battery Mode

CAPACITY_MODE

bit = 0

CAPACITY_MODE

bit = 1

Units

10mW

Charge

Range

132,767mA

132,768 10mW

Discharge

Range

-1 -32,768mA

-1 -32,768 10mW

Granularity

1 Unit

Accuracy

AtRateTimeToFull() (0x05);[0x05]

Description:
Returns the predicted remaining time to fully charge the
battery at the AtRate( ) value (mA).

Purpose:
T h e A t R a t e Ti m e To F u l l ( ) f u n c t i o n i s p a r t o f a
two-function call-set used to determine the predicted
remaining charge time at the AtRate value in mA. The
bq2060 updates AtRateTimeToFull() within 1.3s after
the SMBus Host sets the AtRate value. If read before
this delay, the command is No Acknowledged and the er-
ror code in BatteryStatus is set to not ready.

The

bq2060 automatically updates AtRateTimeToFull()
based on the AtRate() value every 20s.

SMBus Protocol: Read Word

Output:

Unsigned integer--predicted time in minutes to
fully charge the battery.

Units: minutes

Range: 0 to 65,534 min

Granularity: 2 min or better

Accuracy:

MaxError()

FullChargeCapacity()/|AtRate()|

Invalid Data Indication: 65,535 indicates the bat-
tery is not being charged.

AtRateTimeToEmpty() (0x06); [0x06]

Description:
Returns the predicted remaining operating time if the
battery is discharged at the AtRate() value.

Purpose:
The AtRateTimeToEmpty() function is part of a
two-function call-set used to determine the remaining
operating time at the AtRate()value.

The bq2060 up-

dates AtRateTimeToEmpty() within 1.3s after the
SMBus Host sets the AtRate() value. If read before this
delay, the command is No Acknowledged, and the error
code in BatteryStatus is set to not ready. The bq2060
automatically updates AtRateTimeToEmpty() based on
the AtRate() value every 20s.

SMBus Protocol: Read Word

Output:

Unsigned integer -- estimated operating time left.

Units: minutes

Range: 0 to 65,534 min

Granularity: 2 min or better

Accuracy: -0, +MaxError()

FullChargeCapacity/|AtRate()|

Invalid Data Indication: 65,535 indicates the bat-
tery is not being discharged.

AtRateOK() (0x07); [0x07]

Description:
Returns a Boolean value that indicates whether or not
the battery can deliver the AtRate( )value of additional
energy for 10 seconds (Boolean). If the AtRate value is
zero or positive, the AtRateOK() function ALWAYS re-
turn-true.

Purpose:
The AtRateOK() function is part of a two-function
call-set used by power management systems to deter-
mine if the battery can safely supply enough energy for
an additional load. The bq2060 updates AtRateOK()
within 1.3s after the SMBus Host sets the AtRate( )
value. If read before this delay, the command is No Ac-
knowledged, and the error code in BatteryStatus is set
to not ready.

The bq2060 automatically updates

AtRateOK() based on the At Rate() value every 20s.

SMBus Protocol: Read Word

Output:

Boolean--indicates if the battery can
supply the additional energy requested.

bq2060

Units: Boolean

Range: TRUE, FALSE

Granularity: not applicable

Accuracy: not applicable

Temperature() (0x08); [0x08]

Description:
Returns the temperature (K) measured by the bq2060.

Purpose:
The Temperature() function provides accurate cell tem-
peratures for use by battery chargers and thermal man-
agement systems. A battery charger can use the tem-
perature as a safety check. Thermal management sys-
tems may use the temperature because the battery is
one of the largest thermal sources in a system.

SMBus Protocol: Read Word

Output:

Unsigned integer--cell temperature in tenth-degree
Kelvin increments.

Units: 0.1

Range: 0 to +6553.5

K {real range}

Granularity: 0.1

Accuracy:

1.5

K (from ideal 103AT thermistor

performance, after calibration)

Voltage() (0x09); [0x09]

Description:
Returns the cell-pack voltage (mV).

Purpose:
The Voltage() function provides power management sys-
tems with an accurate battery terminal voltage. Power
management systems can use this voltage, along with
battery current information, to characterize devices they
control. This ability helps enable intelligent, adaptive
power-management systems.

SMBus Protocol: Read Word

Output:

Unsigned integer--battery terminal
voltage in mV.

Units: mV

Range: 0 to 20,000 mV

Granularity: 1mV

Accuracy:

0.65% (after calibration)

Current() (0x0a); [0x0a]

Description:
Returns the current being supplied (or accepted)
through the battery's terminals (mA).

Purpose:
The Current() function provides a snapshot for the
power management system of the current flowing into
or out of the battery. This information is of particular
use in power-management systems because they can
characterize individual devices and tune their operation
to actual system power behavior.

SMBus Protocol: Read Word

Output:

Signed integer--charge/discharge rate in mA incre-
ments--positive for charge, negative for discharge.

Units: mA

Range: (± 250mV/R

) mA

Granularity: 0.038mV/R

(integer value)

Accuracy: ±1mV/R

(after calibration)

AverageCurrent() (0x0b); [0x0b]

Description:
Returns a value that approximates a one-minute rolling
average of the current being supplied (or accepted)
t h r o u g h t h e b a t t e r y 's t e r m i n a l s ( m A ) .

T h e

AverageCurrent() function will return meaningful val-
ues during the battery's first minute of operation.

Purpose:
The AverageCurrent() function provides the average
current flowing into or out of the battery for the power
management system.

SMBus Protocol: Read Word

Output:

Signed integer--charge/discharge rate in mA incre-
ments--positive for charge, negative for discharge.

Units: mA

Range: (± 250mV/R

) mA

Granularity: 0.038mV/R

(integer value)

Accuracy: ±1mV/R

(after calibration)

MaxError() (0x0c); [0x0c]

Description:
Returns the expected margin of error (%) in the state of
charge calculation. For example, when MaxError() re-

bq2060

turns 10% and RelativeStateOfCharge() returns 50%,
the Relative StateOfCharge() is more likely between 50
and 60%. The bq2060 sets MaxError() to 100% on a full
reset. The bq2060 sets MaxError() to 2% on completion
of a learning cycle, unless the bq2060 limits the learning
cycle to the +512/-256mAh maximum adjustment val-
ues. If the learning cycle is limited, the bq2060 sets
MaxError() to 8% unless MaxError() was already below
8%. In this case MaxError() does not change. The
bq2060 increments MaxError() by 1% after four incre-
ments of CycleCount() without a learning cycle.

If voltage-based corrections are applied to the coulomb
counter, MaxError() is set to 25%.

Purpose:
The MaxError() function has real value in two ways:
first, to give the user a confidence level about the state
of charge and second, to give the power management
system information about how aggressive it should be,
particularly as the battery nears the end of its life.

SMBus Protocol: Read Word

Output:

Unsigned integer--percent uncertainty for selected
information.

Units: %

Range: 2 to 100%

Granularity: 1%

Accuracy: not applicable

RelativeStateOfCharge() (0x0d); [0x0d]

Description:
Returns the predicted remaining battery capacity ex-
pressed as a percentage of FullChargeCapacity() (%).

Purpose:
The RelativeStateOfCharge() function is used to esti-
mate the amount of charge remaining in the battery rel-
ative to the last learned capacity.

SMBus Protocol: Read Word

Output:

Unsigned integer--percent of remaining capacity.

Units: %

Range: 0 to 100%

Granularity: 1%

Accuracy: -0, +MaxError()

AbsoluteStateOfCharge()(0x0e); [0x0e]

Description:
Returns the predicted remaining battery capacity ex-
pressed as a percentage of DesignCapacity() (%). Note
that AbsoluteStateOfCharge() can return values greater
than 100%.

Purpose:
The AbsoluteStateOfCharge() function is used to esti-
mate the amount of charge remaining in the battery rel-
ative to the nominal or DesignCapacity().

SMBus Protocol: Read Word

Output:

Unsigned integer--percent of remaining capacity.

Units: %

Range: 0 to 100+%

Granularity: 1%

Accuracy: -0, +MaxError()

RemainingCapacity() (0x0f); [0x0f]

Description:
Returns the predicted charge or energy remaining in the
battery. The RemainingCapacity() value is expressed in
either charge (mAh at a C/5 discharge rate) or energy
(10mWh at a P/5 discharge rate) depending on the set-
ting of the BatteryMode()'s CAPACITY_MODE bit.

Purpose:
The RemainingCapacity() function returns the battery's
remaining capacity. This information is a numeric indica-
tion of remaining charge or energy given by the Absolute
or Relative StateOfCharge() functions and may be in a
better form for use by power management systems.

SMBus Protocol: Read Word

Output:

Unsigned integer--remaining charge in mAh or
10mWh.

Battery Mode

CAPACITY_MODE

bit = 0

CAPACITY_MODE

bit = 1

Units

mAh

10mWh

Range

065,535mAh

065,535 10mWh

Granularity

mAh

10mWh

Accuracy

-0, +MaxError()

FullChargeCapacity()

bq2060

FullChargeCapacity() (0x10); [0x10]

Description:
Returns the predicted pack capacity when it is fully
charged. The FullChargeCapacity() value is expressed
in either current (mAh at a C/5 discharge rate) or power
(10mWh at a P/5 discharge rate) depending on the set-
ting of the BatteryMode()'s CAPACITY_MODE bit.

Purpose:
The FullChargeCapacity() function provides the user
with a means of understanding the tank size of their
battery. This information, along with information about
the original capacity of the battery, can be presented to
the user as an indication of battery wear.

SMBus Protocol: Read Word

Output:

Unsigned integer--estimated full-charge capacity
in mAh or 10mWh.

Battery Mode

CAPACITY_MODE

bit = 0

CAPACITY_MODE

bit = 1

Units

mAh

10mWh

Range

065,535mAh

065,535 10mWh

Granularity

mAh

10mWh

Accuracy

-0, +MaxError()

FullChargeCapacity()

RunTimeToEmpty() (0x11); [0x11]

Description:
Returns the predicted remaining battery life at the pres-
ent rate of discharge (minutes). The RunTimeToEmpty()
value is calculated based on either current or power de-
pending on the setting of the BatteryMode()'s CAPAC-
ITY_MODE bit.

Purpose:
The RunTimeToEmpty() provides the power management
system with information about the relative gain or loss in
remaining battery life in response to a change in power
policy. This information is NOT the same as the
AverageTimeToEmpty(), which is not suitable to determine
the effects that result from a change in power policy.

SMBus Protocol: Read Word

Output:

Unsigned integer--minutes of operation left.

Units: minutes

Range: 0 to 65,534 min

Granularity: 2 min or better

Accuracy: -0, +MaxError()

FullChargeCapacity()

/ Current()

Invalid Data Indication: 65,535 indicates battery is
not being discharged.

AverageTimeToEmpty() (0x12); [0x12]

Description: Returns a one-minute rolling average of
the predicted remaining battery life (minutes).

The

AverageTimeToEmpty() value is calculated based on ei-
ther current or power depending on the setting of the
BatteryMode()'s CAPACITY_MODE bit.

Purpose:
The AverageTimeToEmpty() displays state-of-charge in-
formation in a more useful way. It averages the instan-
taneous estimations so the remaining time does not ap-
pear to jump around.

SMBus Protocol: Read Word

Output:

Unsigned integer -- minutes of operation left.

Units: minutes

Range: 0 to 65,534 min

Granularity: 2 min or better

Accuracy: -0, +MaxError()

FullChargeCapacity()

/ AverageCurrent()

Invalid Data Indication: 65,535 indicates battery is
not being discharged.

AverageTimeToFull() (0x13); [0x13]

Description: Returns a one-minute rolling average of
the predicted remaining time until the battery reaches
full charge (minutes).

Purpose:

The AverageTimeToFull() function can be

used by the SMBus Host's power management system to
aid in its policy. It may also be used to find out how long
the system must be left on to achieve full charge.

SMBus Protocol: Read Word

Output:

Unsigned integer --remaining time in minutes.

Units: minutes

Range: 0 to 65,534 minutes

Granularity: 2 minutes or better

Accuracy:

MaxError()

FullChargeCapacity() /

AverageCurrent()

Invalid Data Indication: 65,535 indicates the bat-
tery is not being charged.

bq2060

ChargingCurrent() (0x14); [0x14]

Description: Returns the desired charging rate in mA.

Purpose:

The ChargingCurrent() function sets the

m a x i m u m c h a r g e c u r r e n t o f t h e b a t t e r y.

T h e

ChargingCurrent() value should be used in combination
with the ChargingVoltage() value to set the charger's op-
erating point.

Together, these functions permit the

bq2060 to dynamically control the charging profile (cur-
rent/voltage) of the battery. The bq2060 can effectively
turn off a charger by returning a value of 0 for this func-
tion. The charger may be operated as a constant-voltage
source above its maximum regulated current range by
returning a ChargingCurrent() value of 65,535.

SMBus Protocol: Read Word

Output:

Unsigned integer--maximum charger output cur-
rent in mA.

Units: mA

Range: 0 to 65,535mA

Granularity: 1mA

Accuracy: not applicable

Invalid Data Indication:

65,535 indicates that a

charger should operate as a voltage source outside
its maximum regulated current range.

ChargingVoltage() (0x15); [0x15]

Description: Returns the desired charging voltage in
mV.

Purpose: The ChargingVoltage() function sets the max-
i m u m

c h a r g e

v o l t a g e

o f

t h e

b a t t e r y.

T h e

ChargingVoltage() value should be used in combination
with the ChargingCurrent() value to set the charger's
operating point. Together, these functions permit the
bq2060 to dynamically control the charging profile (cur-
rent/voltage) of the battery. The charger may be oper-
ated as a constant-current source above its maximum
r e g u l a t e d

v o l t a g e

r a n g e

b y

r e t u r n i n g

ChargingVoltage() value of 65,535.

SMBus Protocol: Write Word

Output:

Unsigned integer--charger output voltage in mV.

Units: mV

Range: 0 to 65,535mV

Granularity: 1mV

Accuracy: not applicable

Invalid Data Indication:

65,535 indicates the

charger should operate as a current source outside
its maximum regulated voltage range.

BatteryStatus()(0x16); [0x16]

Description: Returns the bq2060's status word (flags).
Some of the BatteryStatus() flags (REMAINING_CA-
PACITY_ALARM and REMAINING_TIME_ALARM)
are calculated based on either current or power depend-
ing on the setting of the BatteryMode()'s CAPAC-
ITY_MODE bit. This is important because use of the
wrong calculation mode may result in an inaccurate
alarm.

Purpose: The BatteryStatus() function is used by the
power-management system to get alarm and status bits,
as well as error codes from the bq2060. This is basically
the same information broadcast to both the SMBus Host
and the Smart Battery Charger by the AlarmWarning()
function except that the AlarmWarning() function sets
the Error Code bits all high before sending the data.

SMBus Protocol: Read Word

Output:

Unsigned integer--Status Register with alarm con-
ditions bit mapped as follows:

Alarm Bits

0x8000

OVER_CHARGED_ALARM

0x4000

TERMINATE_CHARGE_ALARM

0x2000

reserved

0x1000

OVER_TEMP_ALARM

0x0800

TERMINATE_DISCHARGE_ALARM

0x0400

reserved

0x0200

REMAINING_CAPACITY_ALARM

0x0100

REMAINING_TIME_ALARM

Status Bits

0x0080

INITIALIZED

0x0040

DISCHARGING

0x0020

FULLY_CHARGED

0x0010

FULLY_DISCHARGED

Error Codes

0x0007

Unknown Error

0x0006

BadSize

0x0005

Overflow/Underflow

0x0004

AccessDenied

0x0003

UnsupportedCommand

0x0002

ReservedCommand

0x0001

Busy

0x0000

bq2060

Alarm Bits

OVER_CHARGED_ALARM bit is set whenever the
bq2060 detects that the battery is being charged beyond
the Maximum Overcharge limit.

This bit is cleared

when the bq2060 detects that the battery is no longer
being charged (i.e., the bq2060 detects discharge activity
or no activity for the digital filter timeout periods. The
digital filter timeout period (seconds) equates to 10 time
the value shared in Digital Filter EE0x52.)

TERMINATE_CHARGE_ALARM bit is set when the
bq2060 detects that one or more of the battery's charg-
ing parameters are out of range (e.g., its voltage, cur-
rent, or temperature is too high) or when the bq2060 de-
tects a primary charge termination. This bit is cleared
when the parameter falls back into the allowable range,
the termination condition ceases, or when the bq2060
detects that the battery is no longer being charged.

OVER_TEMP_ALARM bit is set when the bq2060 de-
tects that the internal battery temperature is greater
than or equal to the MaxT limit.

This bit is cleared

when the internal temperature falls back into the ac-
ceptable range.

TERMINATE_DISCHARGE_ALARM bit is set when
the bq2060 detects that Voltage() is less than EDV0 or
when the CVUV bit in Pack Status is set indicating that
a Li-Ion cell voltage has dropped below the limit pro-
grammed in Cell Under / Over Voltage. The bit is
cleared when Voltage() is greater than EDV0 or when
the CVUV bit is cleared.

REMAINING_CAPACITY_ALARM bit is set when the
bq2060 detects that RemainingCapacity() is less than
that set by the RemainingCapacityAlarm() function.
This bit is cleared when either the value set by the
RemainingCapacityAlarm() function is lower than the
RemainingCapacity() or when the RemainingCapacity()
is increased by charging.

REMAINING_TIME_ALARM bit is set when the
bq2060 detects that the estimated remaining time at the
present discharge rate is less than that set by the
RemainingTimeAlarm() function. This bit is cleared when
either the value set by the RemainingTimeAlarm() func-
tion is lower than the AverageTimeToEmpty() or when the
AverageTimeToEmpty() is increased by charging.

Status Bits

INITIALIZED bit is set when the bq2060 is has de-
tected a valid load of EEPROM. It is cleared when the
bq2060 detects an improper EEPROM load.

DISCHARGING bit is set when the bq2060 determines
that the battery is not being charged. This bit is cleared
when the bq2060 detects that the battery is being
charged.

FULLY_CHARGED bit is set when the bq2060 detects
a primary charge termination or an overcharged condi-
tion. It is cleared when RelativeStateOfCharge() is less
than or equal to the programmed Fully Charged Clear %
in EE 0x4c.

FULLY_DISCHARGED bit is set when Voltage() is less
than the EDV2 threshold. This bit is cleared when the
Relative StateOfCharge() is greater than or equal to 20%.

Error Codes

Description

The bq2060 processed the function

code without detecting any errors.

Busy

The bq2060 is unable to process the

function code at this time.

Reserved

The bq2060 detected an attempt to

read or write to a function code

reserved by this version of the

specification. The 2060 detected an

attempt to access an unsupported

optional manufacturer function code.

Unsupported

The bq2060 does not support this

function code which is defined in this

version of the specification.

AccessDenied

The bq2060 detected an attempt to

write to a read-only function code.

Over/Underflow

The bq2060 detected a data overflow

or underflow.

BadSize

The bq2060 detected an attempt to

write to a function code with an

incorrect data block.

UnknownError

The bq2060 detected an

unidentifiable error.

CycleCount()(0x17); [0x17]

Description: Returns the number of cycles the battery
has experienced. The mAh value of each count is deter-
mined by programming the Cycle Count Threshold value
in EE 0x3c0x3d. The bq2060 saves the cycle count
value to Cycle Count EE 0x0e0x0f after an update to
CycleCount().

Purpose: The CycleCount() function provides a means
to determine the battery's wear. It may be used to give
advanced warning that the battery is nearing its end of
life.

SMBus Protocol: Read Word

Output:

Unsigned integer--count of total charge removed
from the battery over its life.

Units: cycle

Range: 0 to 65,534 cycles 65,535 indicates battery
has experienced 65,535 or more cycles.

bq2060

Granularity: 1 cycle

Accuracy: absolute count

DesignCapacity() (0x18); [0x18]

Description: Returns the theoretical or nominal capac-
ity of a new pack. The DesignCapacity() value is ex-
pressed in either current (mAh at a C/5 discharge rate)
or power, (10mWh at a P/5 discharge rate) depending on
the setting of the BatteryMode()'s CAPACITY_MODE
bit.

Purpose: The DesignCapacity() function is used by the
SMBus Host's power management in conjunction with
FullChargeCapacity() to determine battery wear. The
power management system may present this informa-
tion to the user and also adjust its power policy as a re-
sult.

SMBus Protocol: Read Word

Output:

Unsigned integer--battery capacity in mAh or
10mWh.

Battery Mode

CAPACITY_MODE

bit = 0

CAPACITY_MODE

bit = 1

Units

mAh

10mWh

Range

065,535mAh

065,535 10mWh

Granularity

Not applicable

Accuracy

Not applicable

DesignVoltage() (0x19); [0x19]

Description: Returns the theoretical voltage of a new
pack (mV). The bq2060 sets DesignVoltage() to the value
programmed in Design Voltage EE0x120x13.

Purpose: The DesignVoltage() function can be used to
give additional information about a particular Smart
Battery's expected terminal voltage.

SMBus Protocol: Read Word

Output:

Unsigned integer--the battery's designed terminal
voltage in mV

Units: mV

Range: 0 to 65,535 mV

Granularity: not applicable

Accuracy: not applicable

SpecificationInfo() (0x1a); [0x1a]

Description: Returns the version number of the Smart
Battery specification the battery pack supports, as well
as voltage and current scaling information in a packed
unsigned integer. Power scaling is the product of the
voltage scaling times the current scaling.

The

SpecificationInfo is packed in the following fashion:
(SpecID_H

0x10 + SpecID_L) + (VScale + IPScale

10)

0x100.

The bq2060 VScale (voltage scaling) and IPScale (cur-
rent scaling) should always be set to zero. The bq2060
sets SpecificationInfo() to the value programmed in
Specification Information EE 0x140x15.

Purpose:

The SpecificationInfo() function is used by

the SMBus Host's power management system to deter-
mine what information the Smart Battery can provide.

SMBus Protocol: Read Word

Output:

Unsigned integer--packed specification number
and scaling information.

Field

Bits

Used

Format

Allowable Values

SpecID_L

0...3

4-bit binary

value

015

SpecID_H

4...7

4-bit binary

value

015

VScale

8...11

4-bit binary

value

0 (multiplies voltage

by 10^ VScale)

IPScale

12...15

4-bit binary

value

0 (multiplies current

by 10 ^ IPScale)

ManufactureDate() (0x1b); [0x1b]

Description:

This function returns the date the cell

pack was manufactured in a packed integer. The date is
packed in the following fashion: (year-1980)

512 +

month

32 + day. The bq2060 sets ManufactureDate()

to the value programmed in Manufacture Date EE
0x160x17.

Purpose: The ManufactureDate() provides the system
with information that can be used to uniquely identify a
particular battery pack when used in conjunction with
SerialNumber().

SMBus Protocol: Read Word

Output:

Unsigned integer--packed date of manufacture.

bq2060

Field

Bits Used

Format

Allowable Values

Day

0...4

5-bit binary

value

031 (corresponds to

date)

Month

5...8

4-bit binary

value

112 (corresponds to

month number)

Year

9...15

7-bit binary

value

0127 (corresponds to

year biased by 1980)

SerialNumber() (0x1c); [0x1c]

Description: This function is used to return a serial
number.

This number, when combined with the

ManufacturerName(), the DeviceName(), and the
ManufactureDate(), uniquely identifies the battery (un-
signed int).

The bq2060 sets SerialNumber() to the

value programmed in Serial Number EE 0x180x19.

Purpose: The SerialNumber() function can be used to
identify a particular battery. This may be important in
systems that are powered by multiple batteries where
the system can log information about each battery that
it encounters.

SMBus Protocol: Read Word

Output:

Unsigned integer

ManufacturerName() (0x20); [0x20-0x25]

Description: This function returns a character array
containing the battery's manufacturer's name. For ex-
ample, MyBattCo would identify the Smart Battery's
m a n u f a c t u r e r a s M y B a t t C o . T h e b q 2 0 6 0 s e t s
ManufacturerName() to the value programmed in Man-
ufacturer Name EE 0x200x2a.

Purpose:

The ManufacturerName() function returns

the name of the Smart Battery's manufacturer.

The

manufacturer's name can be displayed by the SMBus
Host's power management system display as both an
identifier and as an advertisement for the manufacturer.
The name is also useful as part of the information re-
quired to uniquely identify a battery.

SMBus Protocol: Read Block

Output:

String--character string with maximum length of
11 characters (11+length byte).

DeviceName() (0x21); [0x28-0x2b]

Description: This function returns a character string
that contains the battery's name.

For example, a

DeviceName() of BQ2060A would indicate that the bat-
t e r y i s a m o d e l B Q 2 0 6 0 A . T h e b q 2 0 6 0 s e t s
DeviceName() to the value programmed in Device Name
EE 0x300x37.

Purpose: The DeviceName() function returns the bat-
tery's name for identification purposes.

SMBus Protocol: Read Block

Output:

String--character string with maximum length of 7
characters (7+length byte).

DeviceChemistry() (0x22); [0x30-0x32]

Description: This function returns a character string
that contains the battery's chemistry. For example, if
the DeviceChemistry() function returns NiMH, the bat-
tery pack would contain nickel metal hydride cells. The
bq2060 sets DeviceChemistry() to the value pro-
grammed in Device Chemistry EE 0x400x44.

Purpose:

The DeviceChemistry() function gives cell

chemistry information for use by charging systems. The
bq2060 does not use DeviceChemisty() values for inter-
nal charge control or fuel gauging.

SMBus Protocol: Read Block

Output:

String--character string with maximum length of 4
characters (4+length byte).

Note: The following is a partial list of chemistries and
their expected abbreviations. These abbreviations are
NOT case sensitive.

Lead acid

PbAc

Lithium ion

LION

Nickel cadmium

NiCd

Nickel metal hydride

NiMH

Nickel zinc

NiZn

Rechargeable alkaline-manganese

RAM

Zinc air

ZnAr

ManufacturerData() (0x23); [0x380x3a]

Description: This function allows access to the manu-
facturer data contained in the battery (data). The
bq2060 stores seven critical operating parameters in
this data area.

Purpose:

The ManufacturerData() function may be

used to access the manufacturer's data area. The data
fields of this command reflect the programming of five
critical EEPROM locations and can be used to facilitate
evaluation bq2060 under various programming sets.
The ManufacturerData() function returns the following
information in order: Control Mode, Digital Filter,
Self-Discharge Rate, Battery Low %, Near Full, and the
pending EDV threshold voltage (low byte and high
byte.)

SMBus Protocol: Read Block

bq2060

Output:

Block data--data that reflects EEPROM program-
ming as assigned by the manufacturer with maxi-
mum length of 7 characters (7+length byte).

Pack Status and Pack Configuration (0x2f);
[0x2f]

This function returns the Pack Status and Pack Config-
uration registers. The Pack Status register contains a
number of status bits relating to bq2060 operation. The
Pack Status register is the least significant byte of the
word. The Pack Configuration register is the most sig-
nificant byte of the word. The byte reflects how the
bq2060 is configured as defined by the value pro-
grammed in Pack Configuration in EE 0x3f.

The Pack Status Register consists of the following bits:

OCE

The OCE bit indicates that offset cancellation is en-
abled. The bq2060 sets this bit after VFC offset calibra-
tion is complete.

Offset calibration is not enabled

Offset calibration is enabled

EDV2

The EDV2 bit indicates that Voltage() is less than the
EDV2 threshold.

Voltage() > EDV2 threshold (discharging)

Voltage()

EDV2 threshold

EINT

The EINT bit indicates that the VFC has detected a
charge or discharge pulse.

No charge/discharge activity detected

Charge/discharge activity detected.

VDQ

The VDQ bit indicates if the present discharge cycle is
valid for an FCC update.

Discharge cycle is not valid

Discharge cycle is valid

COK

The COK bit indicates the status of the CFC pin of the
bq2060.

CFC pin is low

CFC pin is high

DOK

The DOK bit indicates the status of the DFC pin of the
bq2060.

DFC pin is low

DFC pin is high

CVOV

The CVOV bit indicates that a secondary Li-Ion protec-
tion limit has been exceeded. It is set if any individual
cell exceeds the programmed high voltage limit, if the
pack voltage exceeds the overvoltage threshold, or if an
over temperature condition occurs. The bit is not latched
and merely reflects the present overvoltage status.

No secondary protection limits exceeded

A secondary protection limit exceeded

CVUV

The CVUV bit indicates if any individual cell falls below
the programmed low-voltage limit. The bit applies to
lithium batteries only. The bit is not latched and merely
reflects the present undervoltage status.

All series cells are above the low-voltage limit

A series cell is below the low voltage limit

VCELL4VCELL1 (0x3c0x3f); [0x3c0x3f]

These functions return the calculated voltages in mV at
the VCELL

through VCELL

inputs.

EEPROM

General

The bq2060 accesses the external EEPROM during a
full reset and when storing historical data. During an
EEPROM access, the V

OUT

pin becomes active and the

bq2060 uses the ESCL and ESDA pins to communicate
with the EEPROM. The EEPROM stores basic configu-
ration information for use by the bq2060. The EEPROM
must be programmed correctly for proper bq2060 opera-
tion.

Memory Map

Table 10 shows the memory map for the EEPROM. It
also contains example data for a 10 series NiMH and a
3s3p Li-Ion battery pack with a 0.05

sense resistor.

bq2060

OCE

EDV2

EINT

VDQ

COK DOK CVOV

CVUV

EEPROM

Address

Name

Chemistry

NiMH

Example

Data

Li-Ion

Example

Data

MSB LSB

MSB

LSB

0x00

0x01

Check Byte 1

Li-Ion, Nickel

15487

0x02

0x03

Remaining Time Alarm

Li-Ion, Nickel

10 minutes

0x04

0x05 Remaining Capacity Alarm

Li-Ion, Nickel

350mAh

400mAh

0x06

EDV A0 Impedance Age

Factor

Li-Ion, Nickel

0x07

Reserved

0x08

0x09

Reserved

0x0a

0x0b

Charging Voltage

Li-Ion, Nickel

18000mV

12600mV

0x0c

0x0d

Reserved

128

0x0e

0x0f

Cycle Count

Li-Ion, Nickel

0x10

0x11

Reserved

0x12

0x13

Design Voltage

Li-Ion, Nickel

12000mV

10800mV

0x14

0x15

Specification Information

Li-Ion, Nickel

v1.1/PEC

0x16

0x17

Manufacture Date

Li-Ion, Nickel 2/25/99=9817

2/25/99=9817

0x18

0x19

Serial Number

Li-Ion, Nickel

0x1a

0x1b

Fast-Charging Current

Li-Ion, Nickel

4000mA

3000mA

0x1c

0x1d

Maintenance Charging

Current

Li-Ion, Nickel

200mA

0mA

0x1e

0x1f

Pre-Charge Current

Li-Ion, Nickel

800mA

100mA

0x20

Manufacturer Name Length Li-Ion, Nickel

0x21

Character 1

Li-Ion, Nickel

0x22

Character 2

Li-Ion, Nickel

0x23

Character 3

Li-Ion, Nickel

0x24

Character 4

Li-Ion, Nickel

0x25

Character 5

Li-Ion, Nickel

0x26

Character 6

Li-Ion, Nickel

0x27

Character 7

Li-Ion, Nickel

0x28

Character 8

Li-Ion, Nickel

0x29

Character 9

Li-Ion, Nickel

0x2a

Character 10

Li-Ion, Nickel

0x2b

Light Discharge Current

Li-Ion, Nickel

0x2c

0x2d

Reserved

0x2e

0x2f

Maximum Overcharge

Li-Ion, Nickel

200mAh

256mAh

0x30

Device Name Length

Li-Ion, Nickel

0x31

Character 1

Li-Ion, Nickel

0x32

Character 2

Li-Ion, Nickel

0x33

Character 3

Li-Ion, Nickel

0x34

Character 4

Li-Ion, Nickel

(Continued on next page)
Note:

Reserved locations must be set as shown. Locations marked with an * are calibration values that can be
adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial
setting.

Table 10. EEPROM Memory Map

bq2060

EEPROM

Address

Name

Chemistry

NiMH

Example

Data

Li-Ion

Example

Data

MSB

LSB

MSB

LSB

0x35

Character 5

Li-Ion, Nickel

0x36

Character 6

Li-Ion, Nickel

0x37

Character 7

Li-Ion, Nickel

0x38

0x39

Last Measured Discharge

Li-Ion, Nickel

4000mAh

4050mAh

0x3a

0x3b

Pack Capacity

Li-Ion, Nickel

4000mAh

4050mAh

0x3c

0x3d

Cycle Count Threshold

Li-Ion, Nickel

500mAh

3240mAh

0x3e

Reserved

0x3f

Pack Configuration

Li-Ion, Nickel

232

246

0x40

Device Chemistry Length

Li-Ion, Nickel

0x41

Character 1

Li-Ion, Nickel

0x42

Character 2

Li-Ion, Nickel

0x43

Character 3

Li-Ion, Nickel

0x44

Character 4

Li-Ion, Nickel

0x45

MaxT DeltaT

Li-Ion, Nickel

50C, 3.0

50C, 4.6

0x46

0x47

Overload Current

Li-Ion, Nickel

6000mA

0x48

Overvoltage Margin

Li-Ion, Nickel

800mV

0x49

Overcurrent Margin

Li-Ion, Nickel

512mA

0x4a

Reserved

Nickel

Cell Under/Over Voltage

Li-Ion

118

0x4b

Fast Charge Termination %

Li-Ion, Nickel

96%

100%

0x4c

Fully Charged Clear %

Li-Ion, Nickel

90%

95%

0x4d

Charge Efficiency

Li-Ion, Nickel

97%

100%

0x4e

Current Taper Threshold

Li-Ion

200mA

DeltaT Time

Nickel

180s

0x4f

Holdoff Time

Nickel

240s

Current Taper Qual Voltage

Li-Ion

128mV

0x50

Manufacturers Data Length Li-Ion, Nickel

0x51

Control Mode

Li-Ion, Nickel

0x52

Digital Filter

Li-Ion, Nickel

0x53

Self-Discharge Rate

Li-Ion, Nickel

0.21%

0x54

Battery Low %

Li-Ion, Nickel

0x55

Near Full

Li-Ion, Nickel

200mAh

0x56

0x57

Reserved

0x58

0x59

Reserved

0x5a

0x5b

Reserved

(Continued on next page)
Note:

Table 10. EEPROM Memory Map (Continued)

bq2060

EEPROM

Address

Description

Chemistry

NiMH

Example

Data

Li-Ion

Example

Data

MSB

LSB

MSB LSB

0x5c

0x5d

Reserved

0x5e

0x5f

VFC Offset*

Li-Ion, Nickel

0x60

VFC Offset*

Li-Ion, Nickel

0x61

Temperature Offset*

Li-Ion, Nickel

0x62

ADC Offset*

Li-Ion, Nickel

0x63

Cell 2 Calibration Factor*

Li-Ion

Efficiency Temperature

Compensation

Nickel

0.25%

0x64

Cell 3 Calibration Factor*

Li-Ion

Efficiency Drop Off

Percentage

Nickel

96%

0x65

Cell 4 Calibration Factor*

Li-Ion

Efficiency Reduction Rate

Nickel

0x66

0x67

ADC Voltage Gain*

Li-Ion, Nickel

16 : 1

0x68

0x69

ADC Sense Resistor Gain*

Li-Ion, Nickel

0.05

0x6a

0x6b

VFC Sense Resistor Gain*

Li-Ion, Nickel

0.05

0x6c

0x6d

VOC 25%

Li-Ion, Nickel

11500mV

10550mV

0x6e

0x6f

VOC 50%

Li-Ion, Nickel

12500mV

10750mV

0x70

0x71

VOC 75%

Li-Ion, Nickel

13500mV

11200mV

0x72

0x73

EDVF/EDV0

Li-Ion, Nickel

9500mV

10265mV

0x74

0x75

EMF/ EDV1

Li-Ion, Nickel

10000mV

11550

0x76

0x77

EDV T0 Factor

Li-Ion, Nickel

4475

0x78

0x79

EDV C1/C0 Factor/EDV2

Li-Ion, Nickel

10500mV

C1 = 0

C0 = 235

0x7a

0x7b

EDV R0 Factor

Li-Ion, Nickel

5350

0x7c

0x7d

EDV R1 Factor

Li-Ion, Nickel

250

0x7e

0x7f

Check Byte 2

Li-Ion, Nickel

42330

Note:

Reserved locations must be set as shown. Locations marked with an * are calibration values that can be adjusted
for maximum accuracy. For these locations the table shows the appropriate default or initial setting.

Table 10. EEPROM Memory Map (Continued)

bq2060

EEPROM Programming

The following sections describes the function of each
EEPROM location and how the data is to be stored.

Fundamental Parameters

Sense Resistor Value

Two factors are used to scale the current related mea-
surements. The 16-bit ADC Sense Resistor Gain value
in EE 0x680x69 scales Current() to mA.

Adjusting

ADC Sense Resistor Gain from its nominal value pro-
vides a method to calibrate the current readings for sys-
tem errors and the sense resistor value (R

) . The nomi-

nal value is set by

ADC Sense Resistor Gain

625

(Rs)

(4)

The 16-bit VFC Sense Resistor Gain in EE 0x6a0x6b
scales each VFC interrupt to mAh. VFC Sense Resistor
Gain is based on the resistance of the series sense resis-
tor. The following formula computes a nominal or start-
ing value for VFC Sense Resistor Gain from the sense re-
sistor value.

VFC Sense Resistor Gain

409.6

(Rs)

(5)

Sense resistor values are limited to the range of 0.00916
to 0.100

Digital Filter

The digital filter threshold, VDF (

V), is set by the value

stored in Digital Filter EE 0x52.

Digital Filter

2250

VDF

(6)

Cell Characteristics

Battery Pack Capacity and Voltage

Pack capacity in mAh units is stored in Pack Capacity
EE 0x3a0x3b. In mAh mode, the bq2060 copies Pack
Capacity to DesignCapacity(). In mWh mode, the bq2060
multiplies Pack Capacity by Design Voltage EE
0x120x13 to calculate DesignCapacity() scaled to
10mWh. Design Voltage is stored in mV.

The initial value for Last Measured Discharge in mAh is
stored in EE 0x380x39. Last Measured Discharge is
modified over the course of pack usage to reflect cell ag-
ing under the particular use conditions. The bq2060 up-
dates Last Measured Discharge in mAh after a capacity

learning cycle. The bq2060 uses the Last Measured Dis-
charge value to calculate FullChargeCapacity() in mAh
or 10mWh mode.

EDV Thresholds and Near Full Percentage

The bq2060 uses three pack voltage thresholds to pro-
vide voltage-based warnings of low battery capacity.
The bq2060 uses the values stored in EEPROM for the
EDV0, EDV1, and EDV2 values or calculates the three
thresholds from a base value and the temperature, ca-
pacity, and rate adjustment factors stored in EEPROM.
If EDV compensation is disabled then EDV0, EDV1, and
EDV2 are stored directly in mV in EE 0x720x73, EE
0x740x75, and EE 0x780x79, respectively.

For capacity correction at EDV2, Battery Low % EE
0 x 5 4 c a n b e s e t a t a d e s i r e d s t a t e - o f - c h a r g e ,
STATEOFCHARGE%, in the range of 5 to 20%. Typical
values for STATEOFCHARGE% are 712% representing
7 12% capacity.

Battery Low % = STATEOFCHARGE%

2.56

(7)

The bq2060 updates FCC if a qualified discharge occurs
from a near-full threshold to EDV2. The desired
near-full threshold window, NFW (mAh), is programmed
in Near Full in EE 0x55.

Near Full =

NFW

(8)

EDV Discharge Rate and Temperature Com-
pensation

If EDV compensation is enabled, the bq2060 calculates
battery voltage to determine EDV0, EDV1, and EDV2
thresholds as a function of battery capacity, tempera-
ture, and discharge load.

The general equation for

EDV0, EDV1, and EDV2 calculation is

(9)

EDV0,1,2 = EMF

- |I

LOAD

where

EMF is a no-load battery voltage that is higher than
the highest EDV threshold that is computed. EMF is
programmed in mV in EMF/EDV1 EE 0x740x75.

LOAD

is the current discharge load.

is the factor that adjusts the EDV voltage for bat-

tery capacity and temperature to match the no-load
characteristics of the battery.

= f ( C0, C + C1, T )

(10)

where

bq2060

C (0%, 3%, or Battery Low % for EDV0, EDV1, and
EDV2, respectively) and C0 are the capacity related
EDV adjustment factors. C0 is programmed in the
lower 11 bits of EDV C0 Factor/EDV2 EE 0x7879.
The Residual Capacity Factor is stored in the upper 5
bits of EE 0x780x79.

Residual Capacity Factor C1

RESIDUAL%

2 56

RESIDUAL % is the desired battery capacity remaining
at EDV0 (RM = 0).

T is the current temperature in

represents the resistance of the battery as a

function of temperature and capacity.

= f ( R1 , T0, T, C + C1)

(11)

R0 is the first order rate dependency factor stored in
EDV R0 Factor EE 0x7a0x7b.

T is the current temperature; C is the battery
capacity relating to EDV0, EDV1, and EDV2; and C1
is the desired residual battery capacity remaining at
EDV0 (RM = 0).

R1 adjusts the variation of impedance with battery
capacity. R1 is programmed in EDV R1 Rate Factor
EE 0x7c0x7d.

T0 adjusts the variation of impedance with battery
temperature.

T0 is programmed in EDV T0 Rate

Factor EE 0x760x77.

is the factor that adjusts for changing cell imped-

ance as the battery pack is cycled.

where

= f(A0, CycleCount())

(12)

A0 is the EDV aging factor that is stored in EDV A0
Factor EE 0x06. It should be set to 0 for most
applications.

Typical values for the EDV compensation factors for a
Li-Ion 3s3p 18650 pack are

EMF = 11550

T0 = 4475

C0 = 235

C1 = 0

R0 = 5350

R1 = 250

A0 = 0

The graphs in Figures 7 and 8 show the calculated
EDV0, EDV1, and EDV2 thresholds versus capacity us-
ing the typical compensation values for different
temperatures and loads for a Li-Ion 3s3p 18650 pack.
The compensation values vary widely for different cell
types and manufacturers and must be matched exactly
to the unique characteristics for optimal performance.

Overload Current Threshold

The Overload Current threshold is a 16-bit value stored
in EE 0x46-0x47 in mA units.

Battery Low % = 7%, Load = 500mA

7500

8000

8500

9000

9500

10000

10500

11000

11500

% Capacity

olta

(mV)

45C/500mA

20C/500mA

EDV1

EDV2

Figure 7. EDV Calculations vs. Capacity

for Various Temperatures

Battery Low % =7%, Temperature = 35 C

7000

EDV0

EDV1

EDV2

8000

7500

9000

8500

9500

10000

10500

11000

11500

% Capacity

olta

(mV)

35C/2A

35C/500mA

35C/1A

Figure 8. EDV Calculations vs. Capacity

for Various Loads

bq2060

Midrange Capacity Corrections

Three voltage-based thresholds, VOC25 EE 0x6c0x6d,
VOC50 EE 0x6e0x6f, and VOC75 EE 0x700x71, are
u s e d t o t e s t t h e a c c u r a c y o f t h e R M b a s e d o n
open-circuit pack voltages. These thresholds are stored
in the EEPROM in 2's complement of voltage in mV.
The values represent the open-circuit battery voltage at
which the battery capacity should correspond to the as-
sociated state of charge for each threshold.

Self-Discharge Rate

The nominal self-discharge rate, %PERDAY (% per day),
is programmed in an 8-bit value Self-Discharge Rate EE
0x53 by the following relation:

Self

Discharge Rate

æ
è

ö
ø

256 -

52.73

%PERDAY

(13)

Light Load Current

The amount of light load current in mA, ILEAK, used
for compensation is stored in Light Discharge Current in
EE 0x2b as follows:

Light Disch

Current =

ILEAK

1024

arge

(14)

ILEAK is between 0.044 and 11.2mA.

Charge Efficiency

The bq2060 uses four charge-efficiency factors to com-
pensate for charge acceptance. These factors are coded
in Charge Efficiency, Efficiency Reduction Rate, Effi-
ciency Drop Off Percentage, and Efficiency Temperature
Compensation.

The bq2060 applies the efficiency factor, EFF%, when
RelativeStateOfCharge() is less than the value coded in
Efficiency Drop Off Percentage EE 0x64. When
RelativeStateOfCharge() is greater than or equal to the
value coded in Efficiency Drop Off Percentage, EFF%
and ERR% determine the charge efficiency rate. ERR%
defines the percent efficiency reduction per percentage
point of RelativeStateOfCharge() over Efficiency Drop
Off Percentage. EFF% is encoded in High Charge
Efficiency EE 0x4d according to the following equation:

Charge Efficiency = 10

(EFF% - 74.5)

(15)

where

74.5

EFF%

ERR% is encoded in Efficiency Reduction Rate EE 0x65
according to the following equation:

Efficiency Reduction Rate =

ERR%

0.0125

(16)

where

ERR%

3.19

The Efficiency Drop Off Percentage is stored in 2's com-
plement of percent.

The bq2060 also adjusts the efficiency factors for temper-
ature. TEFF% defines the percent efficiency reduction per
degree C over 25

C. TEFF% is encoded in Efficiency Tem-

perature Compensation EE 0x63 according to the follow-
ing equation

(17)

Efficiency Temperature Compensation =

TEFF% 1.6

0.0125

where

TEFF%

1.99

The bq2060 applies all four charge-compensation factors
when the CHEM bit in Pack Configuration is not set de-
noting a nickel pack.

(18)

Effective Charge Efficiency Reduction (nickel only)

= ERR%[RSOC() EFF%] + TEFF%[T(

°C) 25]

where

RSOC()

EFF% and T

25°

If CHEM is set denoting a Li-Ion pack, the bq2060 ap-
plies only the value coded in High Charge Efficiency and
makes no other adjustments for charge acceptance.

Charge Limits and Termination
Techniques

Charging Voltage

The 16-bit value, Charging Voltage EE 0x0a-0x0b pro-
grams the ChargingVoltage() value broadcast to a Smart
Charger. It is also sets the base value for determining
overvoltage conditions during charging and voltage com-
pliance during a constant-voltage charging methodology.
It is stored in mV.

Overvoltage

The 8-bit value, Overvoltage Margin EE 0x48, sets the
limit over ChargingVoltage() that is to be considered as
an overvoltage charge-suspension condition. The voltage
in mV above the ChargingVoltage(), VOVM, that should

bq2060

trigger a charge suspend is encoded in Overvoltage Mar-
gin as follows:

Overvoltage Margin

VOVM

(19)

VOVM is between 0 and 4080mV.

Charging Current

ChargingCurrent() values are either broadcast to a
Level 2 Smart Battery Charger or read from the bq2060
by a Level 3 Smart Battery Charger. The bq2060 sets
the value of ChargingCurrent(), depending on the
charge requirements and charge conditions of the pack.

W h e n f a s t c h a r g e i s a l l o w e d , t h e b q 2 0 6 0 s e t s
ChargingCurrent() to the rate programmed in Fast
Charging Current EE 0x1a-0x1b.

W h e n f a s t c h a r g e t e r m i n a t e s , t h e b q 2 0 6 0 s e t s
ChargingCurrent() to zero and then to the Maintenance
Charging Current EE 0x1c-0x1d when the termination
condition ceases.

When Voltage() is less than EDV0, the bq2060 sets
ChargingCurrent() to Pre-charge Current EE 0x1e-0x1f.
Typically this rate is larger than the maintenance rate
to charge a deeply depleted pack up to the point where it
may be fast charged.

Fast Charging Current, Maintenance Charging Current,
and Pre-Charge Current are stored in mA.

Charge Suspension

During charge, the bq2060 compares the current to the
ChargingCurrent() plus the value IOIM. If the pack is
charged at a current above the ChargingCurrent() plus
IOIM, the bq2060 sets ChargingCurrent() set to zero to
stop charging. IOIM is programmed in the EEPROM
value, Overcurrent Margin, encoded as

Overcurrent Margin

IOIM

(20)

Overcurrent Margin EE 0x49 may be used to program
IOIM values of 0 to 4080mA in 16mA steps.

The desired temperature threshold for charge suspen-
sion, MAXTEMP, may be programmed between 45

and 69

C in 1.6

C steps. MaxT DeltaT EE 0x45 (most

significant nibble) is stored in a 4-bit value as shown:

MaxT

é
ë
ê

ù
û
ú

MAXTEMP

1.6

(21)

The bq2060 suspends fast charge when fast charge con-
tinues past full by the amount programmed in Maxi-
mum Overcharge EE 0x2e-0x2f.

Maximum Overcharge

is programmed in 2s complement form of charge in mAh.

FULLY_CHARGED Bit Clear Threshold

The bq2060 clears the FULLY_CHARGED bit in
BatteryStatus() when RelativeStateOfCharge() reaches
the value, Fully Charged Clear % EE 0x4c. Fully
Charged Clear % is an 8-bit value and is stored as a 2's
complement of percent.

Fast Charge Termination Percentage

The bq2060 sets RM to a percentage of FCC on charge
termination if the CSYNC bit is set in the Pack Configu-
ration register. The percentage of FCC is stored in Fast
Charge Termination % in EE 0x4b. The value is stored
in 2's complement of percent.

Cycle Count Threshold

Cycle Count Threshold 0x3c0x3d sets the number of
mAh that must be removed from the battery to incre-
ment CycleCount(). Cycle Count Threshold is a 16-bit
value stored in 2's complement of charge in mAh.

t Rate Programming

The

portion of the

rate is programmed in

DeltaT, the low nibble of MaxT DeltaT EE 0x45 (least
significant nibble).

The

portion is programmed in

DeltaT Time EE 0x4e.

t =

[

]

[

]

DeltaT

DeltaT Time

* +

é
ë
ê

ù
û
ú

320 -

/ 10

(22)

DeltaT

(

DeltaT_Time

t (s)

1.6

320

1.8

300

2.0

280

2.2

260

2.4

240

2.6

220

2.8

200

3.0

180

3.2

160

3.4

140

3.6

120

3.8

100

4.0

4.2

4.4

4.6

t Hold-off Timer Programming

The hold-off timer is programmed in the lower nibble of
Holdoff Time EE 0x4f. The hold-off time is 320s minus
20 times the Holdoff Time value.

bq2060

Hold-off

Time

Hold-off
Time (s)

Hold-off

Time

Hold-off
Time (s)

320

160

300

140

280

120

260

100

240

220

200

180

Current Taper Termination Characteristics

Two factors in the EEPROM set the current taper termi-
nation for Li-Ion battery packs. The two coded locations
are Current Taper Qual Voltage EE 0x4f and Current
Taper Threshold EE 0x4e. Current taper termination oc-
curs during charging when the pack voltage is above the
charging voltage minus CELLV (mV) and the charging
current is below the threshold coded in Current Taper
Threshold for at least 40s.

Current Taper Qual Voltage =

CELLV

(23)

Current Taper Threshold =

0.5625

(24)

where i = the desired current termination threshold in
mA, and R

= VFC sense resistor in ohms.

Pack Options

Pack Configuration

Pack Configuration EE 0x3f contains bit-programmable
features.

DMODE

The DMODE bit determines whether the LED outputs
will

indicate

AbsoluteStateOfCharge()

RelativeStateOfCharge()

LEDs reflect AbsoluteStateOfCharge()

LEDs reflect RelativeStateOfCharge()

SEAL

The SEAL bit determines the SMBus access state of the
bq2060 on reset

SMBus commands (0x000xff) are accessible for
both read and write.

SMBus read access is limited to commands
(0x050x1c) and (0x200x23). SMBus read/write
access is limited to commands (0x000x04), (0x2f),
and (0x3c0x3f).

CSYNC

In usual operation of the bq2060, the CSYNC bit is set
so that the coulomb counter is adjusted when a fast
charge termination is detected. In some applications, es-
pecially those where an externally controlled charger is
used, it may be desirable NOT to adjust the coulomb
counter. In these cases the CSYNC bit should be
cleared.

The bq2060 does not alter RM at the time of a valid
charge termination.

The bq2060 updates RM with a programmed per-
centage of FCC at a valid charge termination.

CEDV

The CEDV bit determines whether the bq2060 imple-
ments automatic EDV compensation to calculate the
EDV0, EDV1 and EDV2 thresholds base on rate, tem-
perature, and capacity. If reset, the bq2060 uses the
fixed values programmed in EEPROM for EDV0, EDV1
and EDV2. If set the bq2060 calculates EDV0, EDV1
and EDV2.

EDV compensation disabled

EDV compensation enabled

VCOR

The VCOR bit enables the midrange voltage correction
algorithm. When set, the bq2060 compares the pack
voltage to RM and may adjust RM according to the val-
ues programmed in VOC25, VOC50, and VOC75.

Midrange corrections disabled

Midrange corrections enabled

CHEM

The CHEM bit configures the bq2060 for nickel packs
(NiCd or NiMH) or Li-Ion packs. When set the bq2060
employs the configuration parameters in EEPROM des-
ignated for Li-Ion. When not set, the bq2060 employs
the configuration parameters designated for nickel.

The bq2060 uses nickel configuration parameters.

The bq2060 uses Li-Ion configuration parameters.

LCC0 and LCC1

The LCC0 and LCC1 bits configure the cell voltage in-
puts (VCELL

bq2060

DMODE SEAL

CSYNC

CEDV

VCOR

CHEM

LCC1

LCC0

No. of Series

Cells

LCC1 LCC0

Cell Voltage

Inputs

VCELL

= Cell Stack

VCELL

= Cell 1

VCELL

= Cell 2

VCELL

= Cell 1

VCELL

= Cell 2

VCELL

= Cell 3

VCELL

= Cell 1

VCELL

= Cell 2

VCELL

= Cell 3

VCELL

= Cell 4

For Li-Ion packs with individual measurements, LCC0
and LCC1 define the number of series elements and
their voltage measurement inputs. In each case (2, 3, or
4), the bq2060 uses the highest numbered cell voltage
input to measure the pack voltage measurement as re-
turned with Voltage(). For nickel chemistries or Li-Ion
without single-cell measurements, LCC0 and LCC1
must be set to 00. VCELL

is the pack voltage input for

this programming.

Remaining Time and Capacity Alarms

Remaining Time Alarm in EE 0x020x03 and Re-
maining Capacity Alarm in 0x040x05set the alarm
thresholds used in the SMBus command codes 0x01 and
0x02, respectively. Remaining Time Alarm is stored in
minutes and Remaining Capacity Alarm in mAh.

Secondary Protection Limits for Li-Ion

The cell undervoltage (V

) and overvoltage (V

) limits

are programmed in Cell Undervoltage/Over Voltage EE
0x4a according to the equations:

Cell Undervoltage/Overvoltage (lower) =

- 4096

(25)

Cell Undervoltage/Overvoltage (upper) =

2048

(26)

Cell Under/Over

Voltage

(upper nibble)

(mV)

Cell Under/Over

Voltage

(lower nibble)

(mV)

2048

4096

2112

4128

2176

4160

2240

4192

2304

4224

2368

4256

2432

4288

2496

4320

2560

4352

2624

4384

2688

4416

2752

4448

2816

4480

2880

4512

2944

4544

3008

4576

Cycle Count Initialization

Cycle Count EE 0x0e0x0f stores the initial value for
the CycleCount() function. It should be programmed to
0x0000.

Control Modes

Control Mode EE0x51 contains additional bit program-
mable features.

NDF

HPE

CPE

LED

NDF

The NDF bit disables the digital filter during discharge
if the SMBC and SMBD lines are high.

Digital filter enabled all the time

Digital filter disabled if SMBC and SMBD are high

HPE

The HPE bit enables/disables PEC transmissions to the
Smart Battery host for master mode alarm messages.

No PEC byte on alarm warning to host

PEC byte on alarm warning to host

CPE

The CPE bit enables/disables PEC transmissions to the
Smart Battery Charger for master mode alarm mes-
sages.

No PEC byte on broadcasts to charger

PEC byte on broadcasts to charger

LED

The LED bit configures the bq2060 for 4 or 5 LED indi-
cation

Selects the 5 LED indication mode

Selects the 4 LED indication mode

bq2060

The SC bit enables learning cycle optimization for a
Smart Charger or independent charge

Learning cycle optimized for independent charger

Learning cycle optimized for Smart Charger

The SM bit enables/disables master mode broadcasts by
the bq2060

Broadcasts to host and charger enabled

Broadcasts to host and charger disabled

I f t h e S M b i t i s s e t , m o d i f i c a t i o n s t o b i t s i n
BatteryMode() will not re-enable broadcasts.

Measurement Calibration

ADC

To describe how the bq2060 calculates reported battery
and individual cell voltages, the following abbreviations
and designations are used:

VCELL

= voltages at the input pins of the

bq2060

VCELL14 = reported cell voltages

Vnl4 = voltages at the different series nodes in the
battery

Voltage() = reported battery voltage

= voltage across the sense resistor

The reported voltages measurements, Voltage() and
VCELL14, may be calibrated by adjusting five 8- or
16-bit registers in EEPROM: ADC Offset in EE0x62,
ADC Voltage Gain in EE 0x660x67, Cell 2 Calibration
Factor in EE 0x63, Cell 3 Calibration Factor in EE 0x64,
and Cell 4 Calibration Factor in EE 0x65.

The bq2060 first computes the node voltages Vnl, Vn2,
Vn3, and Vn4. The node voltages are inputs to the volt-
age dividers to the VCELL

through VCELL

input pins

of the bq2060. The bq2060 computes node voltages to
calculate the five reported voltages by the bq2060: Volt-
age(), VCELL1, VCELL2, VCELL3, and VCELL4.

An ADC Voltage Gain factor of 20,000 is the nominal
value when using the recommended cell-voltage division
ratios of 16:1 on the VCELL

and VCELL

inputs and

8:1 on the VCELL

and VCELL

inputs. The bq2060

subtracts the voltage across the sense resistor from the
measurements so that the reported voltages reflect the
cell-stack voltages only.

The bq2060 compute the node voltages as

(27)

VCELL

32768

1250

é
ë
ê

ù
û
ú*

ADC Offset

ADC Voltage Gain

65536

é
ë
ê

ù
û
ú

(28)

Vn2

VCELL

é
ë
ê

ù
û
ú*

32768

1250

ADC Offset

ADC Voltage Gain

Cell

CalibrationFactor

+ *

é
ë
ê

ù
û
ú

65536

(

)

(29)

Vn3

VCELL

é
ë
ê

ù
û
ú*

32768

1250

ADC Offset

ADC Voltage Gai

[

]

Cell

CalibrationFactor

+ *

é
ë
ê

ù
û
ú

65536

(

)

(30)

Vn4

VCELL

é
ë
ê

ù
û
ú*

32768

1250

ADC Offset

ADC Voltage Gai

[

]

Cell

CalibrationFactor

+ *

é
ë
ê

ù
û
ú

65536

(

)

Note: With LCC1-LCC0 = 00, Cell 4 Calibration
Factor = 0.

ADC Offset adjusts the ADC reading for voltage and cur-
rent measurements. ADC Offset is a signed 8-bit value
that cancels offset present in the circuit with no poten-
tial or current flow. ADC Offset is typically set between
-20 and 20.

The bq2060 uses the computed node voltages to calcu-
late the reported voltages. It does not compute reported
cell voltages greater than the selected number of nodes.
If no individual cell voltages are to be measured,
LCC1LCC0 should be set to 00 and the top of the bat-
tery stack should be connected to a voltage divider to
the VCELL

input.

The bq2060 computes the reported voltages as follows:

Voltage() = Vn4 (LCC1LCC0 = 11 or 00) - V

Voltage() = Vn3 (LCC1LCC0 = 10) - V

Voltage() = Vn2 (LCC1LCC0 = 01) - V

VCELL4 = Vn4 - Vn3

VCELL3 = Vn3 - Vn2

VCELL2 = Vn2 - Vn1

bq2060

VCELL1 = Vn1 - V

Current

The bq2060 scales Current() to mA units by the 16-bit
value ADC Sense Resistor Gain in EE 0x680x69.
Adjusting ADC Sense Resistor Gain from its nominal
value provides a method to calibrate the current read-
ings for variances in the ADC gain, internal voltage ref-
erence, and sense resistor value. The bq2060 calculates
Current() by

(31)

Current() =

[

]

(ADC Reading +

)

ADC Offset

ADC Sense Resistor Gain

,384

The nominal value for ADC Sense Resistor Gain is given
by equation (6).

VFC

To calibrate the coulomb counting measurement for VFC
gain errors and sense resistor tolerance, the value of
VFC Sense Resistor Gain EE 0x6a-0x6b may be adjusted
from its nominal value.

The nominal value of VFC Sense Resistor Gain is given
by equation (5).

The bq2060 VFC circuit can introduce a signal opposite
in sign from that of the inherent device and circuit offset
to cancel this error. The offset calibration routine is ini-
tiated with commands to ManufacturerAccess().

The bq2060 calculates the offset with the calibration
routine and stores the calibration value using the least
21 bits of VFC Offset in EE 0x5e0x60.

The least 20 bits store the offset calibration value
(OCV). The sign of the offset calibration value is positive
if the 21st bit is 0.

OCV =

0.6V

VFC Offset

(32)

Temperature

The bq2060 uses Temperature Offset in EE 0x61 to cali-
brate the Temperature() function for offset. The required
offset adjustment, TOFF (C), sets Temperature Offset ac-
cording to the equation

Temperature Offset = TOFF

(33)

where

-12.8

TOFF

12.7

Constants and String Data

EEPROM Constants

Check/Byte 1

EE 0x000x01 and Check Byte 2 EE

0x7e0x7f must be programmed to 0x3c7f and 0xa55a,
respectively.

Specification Information

Specification Information EE 0x140x15 stores the de-
fault value for the SpecificationInfo() function. It is
stored in EEPROM in the same format as the data re-
turned by the SepcificationInfo().

Manufacture Date

Manufacture Date EE 0x160x17 stores the default
value for the ManufactureDate() function. It is stored in
EEPROM in the same format as the data returned by
the ManufactureDate().

Serial Number

Serial Number EE 0x180x19 stores the default value
for the SerialNumber() function. It is stored in
EEPROM in the same format as the data returned by
the SerialNumber().

Manufacturer Name Data

Manufacturer Name Length EE 0x20 stores the length
o f t h e d e s i r e d s t r i n g t h a t i s r e t u r n e d b y t h e
ManufacturerName() function. Locations EE 0x210x2a
store the characters for ManufacturerName() in ASCII
code.

Device Name Data

Device Name Length EE 0x30 stores the length of the
desired string that is returned by the DeviceName()
function. Locations EE 0x310x37 store the characters
for DeviceName() in ASCII code.

Device Chemistry Data

Device Chemistry Length EE 0x40 stores the length of
t h e d e s i r e d s t r i n g t h a t i s r e t u r n e d b y t h e
DeviceChemistry() function. Locations EE 0x410x44
store the characters for DeviceChemistry() in ASCII
code.

Manufacturers Data Length

Manufacturers Data Length EE 0x50 stores the length
of the desired number of bytes that is returned by the
ManufacturersData() function. It should be set to 7.

bq2060

bq2060

Absolute Maximum Ratings

Symbol

Parameter

Minimum

Maximum

Unit

Notes

--Supply voltage

Relative to V

-0.3

+6.0

All other pins

Relative to V

-0.3

+6.0

OPR

Operating

temperature

-20

+70

°C

Commercial

Note: Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Functional operation

should be limited to the Recommended DC Operating Conditions detailed in this data sheet. Exposure to

DC Electrical Characteristics

(VCC

2.73.7V, TOPR = -2070°C, Unless Otherwise Noted)

Symbol

Parameter

Conditions

Minimum Typical

Maximum

Unit

Supply voltage

2.7

3.3

3.7

Operating current

OUT

inactive

180

235

SLP

Low-power storage mode current

1.5V < V

< 3.7V

LVOUT

OUT

leakage current

OUT

inactive

-0.2

0.2

VOUT

OUT

source current

OUT

active,

OUT

= V

- 0.6V

-5.0

OLS

Output voltage low: LED

LED

, CFC,

DFC

OLS

= 5mA

0.4

Output voltage low: THON, CVON

OLS

= 5mA

0.36

Input voltage low DISP

-0.3

0.8

Input voltage high DISP

2.0

+ 0.3

Output voltage low SMBC, SMBD,

HDQ16, ESCL, ESDA

= 1.0mA

0.4

ILS

Input voltage low SMBC, SMBD,

HDQ16, ESCL, ESDA

-0.3

0.8

IHS

Input voltage high SMBC, SMBD,

HDQ16, ESCL, ESDA

1.7

6.0

Input voltage range VCELL

, TS,

SRC

- 0.3

1.25

RBI data-retention input current

RBI

> 3.0V, V

< 2.0V

RBI

RBI data-retention voltage

1.3

AI1

Input impedance: SR1, SR2

01.25V

AI2

Input impedance: VCELL

, TS, SRC

01.25V

REG Characteristics

OPR

= -2070°C)

Symbol

Parameter

Conditions

Minimum Typical

Maximum

Unit

REG controlled output voltage

JFET: R

(on) < 150

(off) < 3.0V @ 10

3.1

3.3

3.6

REG

REG output current

1.0

VFC Characteristics

= 3.13.6V, T

OPR

= 070°C Unless Otherwise Noted))

Symbol

Parameter

Conditions

Minimum Typical

Maximum

Unit

Input voltage range, V

SR2

and V

SR1

= V

SR2

SR1

0.25

+0.25

SROS

input offset

SR2

= V

SR1

, autocorrection

disabled

250

SRCOS

Calibrated offset

+16

VCO

Supply voltage gain

coefficient (see Note)

= 3.3V

0.8

1.2

%/V

TCO

Temperature gain

coefficient (see note)

Slope for T

OPR

= 20 to 70

0.09

+0.09

%/°C

Total Deviation T

OPR

= 20 to 70

1.6

0.1

Slope for T

OPR

= 0 to 50

0.05

+0.05

%/°C

Total Deviation T

OPR

= 0 to 50

0.6

0.1

INL

Integral nonlinearity

error

OPR

= 050C

0.21

Note: RM

TCO

total deviation is from the nominal gain at 25°C.

bq2060

SMBus AC Specifications

(VCC

2.73.7V, TOPR = -2070

C, Unless Otherwise Noted)

Symbol

Parameter

Conditions

Min.

Typ.

Max.

Unit

SMB

SMBus operating frequency

Slave mode, SMBC 50% duty cycle

100

kHz

MAS

SMBus master clock frequency

Master mode, no clock low slave

extend

51.2

kHz

BUF

Bus free time between start and

stop

4.7

HD:STA

Hold time after (repeated) start

4.0

SU:STA

Repeated start setup time

4.7

SU:STO

Stop setup time

4.0

HD:DAT

Data hold time

Receive mode

Transmit mode

300

SU:DAT

Data setup time

250

TIMEOUT

Error signal/detect

See Note 1

LOW

Clock low period

4.7

HIGH

Clock high period

See Note 2

4.0

LOW:SEXT

Cumulative clock low slave

extend time

See Note 3

LOW:MEXT

Cumulative clock low master

extend time

See Note 4

Notes: 1.

The bq2060 will time out when any clock low exceeds T

TIMEOUT

HIGH

Max. is minimum bus idle time. SMBC = SMBD = 1 for t > 50

s will cause reset of any

transaction involving bq2060 that is in progress.

LOW:SEXT

is the cumulative time a slave device is allowed to extend the clock cycles in one message

from initial start to the stop. The bq2060 typically extends the clock only 20

s as a slave in the read

byte or write byte protocol.

LOW:MEXT

is the cumulative time a master device is allowed to extend the clock cycles in one mes-

sage from initial start to the stop. The bq2060 typically extends the clock only 20

s as a master in

the read byte or write byte protocol.

HDQ16 AC Specifications

(VCC

2.73.7V, TOPR = -2070 C, Unless Otherwise Noted)

Symbol

Parameter

Conditions

Min.

Typ.

Max.

Unit

CYCH

Cycle time, host to bq2060 (write)

190

CYCB

Cycle time, bq2060 to host (read)

190

205

250

STRH

Start hold time, host to bq2060 (write)

STRB

Start hold time, host to bq2060 (read)

DSU

Data setup time

DSUB

Data setup time

Data hold time

100

Data valid time

SSU

Stop setup time

145

SSUB

Stop setup time

145

RSPS

Response time, bq2060 to host

190

320

Break time

190

Break recovery time

Data Sheet Revision History

Change

No.

Page No.

Description

Nature of Change

V-to-F Converter offset

Was: 20

Is: 16

Calibration of true battery

capacity

Was: from a programmable level of full to empty

Is: from programmable near full to near empty levels

Digital filter operation

Was: does not integrate charge or discharge counts

Is: does not measure charge or discharge counts

Was: flowing through the sense resistor because of offset.

Is: flowing through the sense resistor

Figure 2. Bq2060 Operational

Overview

Add Light Discharge Compensation input. Delete Sus-

pend Compensation box.

Equation for value of FCC

Was:

FCC new

DCR

FCC BatteryLow

(

)

(

Is:

FCC(new)

DCR(final)

DCR(initial)

measured dischar

ge to EDV2

(FCC

´ BatteryLow%)

Battery Low%

(value stored in EE 0x54)

2 56

Battery voltage threshold for

qualified discharge

Was: voltage was greater than the EDV2 threshold

Is: voltage was less than the EDV2 threshold

End-of-discharge thresholds

Was: three compensated low-voltage thresholds

Is: three low-voltage thresholds

Table 3 header

Was: Access

Is: SMBus Access

EDV threshold reset

Was: The bq2060 resumes EDV threshold detection after
Current() drops below the overload current threshold.

Is: The bq2060 resumes EDV threshold detection after
Current() drops below the overload current threshold.
Any EDV threshold detected will be reset after 10mAh of
charge are applied.

Self-discharge estimation rate

Was: estimation for 25

Is: estimation rate for 25

Replace times sign with

mathematical bullet

Was:

Self

Disch

e Update Time

per day

· ´

arg

640 13500

256

( %

)

seconds

Is:

Self Disch

e Update Time

n Y

per day

· ·

arg

640 13500

256

( %

)

seconds

Was:

640 13500

256

6750

· ´

per day

( %

)

econds

Is:

640 13500

256

6750

· ·

per day

( %

)

econds

Typos in overcurrent condition

Was: On detecting an overcurrent condition, the bq2060
sets the ChargingCurrent() to zero and sets the
TERMINATE_CHARGE_ALARM bit in Battery
Status(). The overcurrent condition and TERMINATE_
CHARGE_ALARM are cleared when the measured
current drops below the ChargingCurrent plus the
Overcurrent Margin.

Is: On detecting an overcurrent condition, the bq2060
sets the ChargingCurrent() to zero and sets the
TERMINATE_CHARGE_ALARM bit in Battery
Status(). The overcurrent condition and TERMINATE_
CHARGE_ALARM are cleared when the measured
current drops below the ChargingCurrent plus the
Overcurrent Margin.

Typo in Overvoltage

Was: BatteryStat-us()

Is: BatteryStatus()

Overtemperature criterion

Was: An over-temperature condition exists when
Temperature() exceeds the Max T value programmed in
EE 0x45 (most significant nibble).
Is:

An over-temperature condition exists when

Temperature() is greater than or equal to

the Max T

value programmed in EE 0x45 (most significant nibble).

Overtemperature cleared

Was: drops 5 degrees C below the Max T value or 43

Is: is equal to or below (Max T 5

C) or 43

Extensive changes in Table 6:

Alarm and Status Bit Summary

Was: See Table 6 in SLUS035C.

Is: See Table 6 in SLUS035D.

Fifth LED function

Was: A 5th LED can be used with the 4 LED display
option to show when the battery capacity is equal to
100%.
Is: A 5th LED can be used with the 4 LED display option
to show when the battery capacity is

to 100%.

Display activation

Was: Detection of the transition activates the display
and starts a display timer that advances for four
seconds.
Is: Detection of the transition activates the display and
starts a four-second display timer.

Display disabling

Was: Unless noted, EDV0 = 0.

Is: The display is disabled if EDV0 = 1.

SMBus On and Off State

Was: OH State detection

Is: Off State detection

Removal of t

from Figure 6

Was: See Fig. 6 in SLUS035C.

Is: See Fig. 6 in SLUS035D.

ManufacturerAccess description

Was: This function provides writable command codes to
control the bq2060 during normal operation and pack
manufacture.
Is: These commands can be ignored if sent within one
second after a device reset.

Time between settings of

ALARM_MODE bit

Was: An SMBus host that does not want the bq2060 to
be a master on the SMBus must therefore continually
set this bit at least once per 45s . . . .
Is: To prevent the bq2060 from becoming a master on the
SMBus, an SMBus host must therefore continually set
this bit at least once per 50s . . . .

Enabling transmission of

ChargingCurrent() and

ChargingVoltage()

Was: When cleared, the bq2060 transmits the
ChargingCurrent() and ChargingVoltage() values to the
Smart Battery Charger when charging is desired.
Is: When cleared, the bq2060 transmits the
ChargingCurrent() and ChargingVoltage() values to the
Smart Battery Charger.

ChargingCurrent()

Was: Range: 0 to 61,456mA

Is: Range: 0 to 65,535mA

ChargingVoltage()

Was: Range: 0 to 61,456mV

Is: Range: 0 to 65,535mV

Setting OVER_TEMP_ALARM bit

Was: temperature is greater than allowed by the MaxT
limit
Is: temperature is greater than or equal to the MaxT
limit

Setting ManufacturerName()

Was: sets ManufacturerName() to the value programmed
in Manufacturer Name EE 0x200x26
Is: sets ManufacturerName() to the value programmed
in Manufacturer Name EE 0x200x2a

ManufacturerData() description

Was: critical EEPROM programming parameters

Is: critical operating parameters

ManufacturerData() purpose

Was: calculated EDV threshold

Is: pending EDV threshold voltage

Move paragraph from CVUV to

Pack Status and Pack Configura-

tion

Was:

Is: The Pack Configuration register reflects how the

bq2060 is configured as defined by the value

programmed in Pack Configuration in EE 0x3f.

Introduce Pack Status Register

table

Was:

Is: The Pack Status Register consists of the following

bits:

Pack Status EDV2 bit = 0

Was: Voltage() > EDV2 threshold

Is: Voltage() > EDV2 threshold (discharging)

EINT bit function

Was: The EDV2 bits indicate

Is: The EDV2 bit indicates

Setting the digital filter threshold,

VDF (

Was: The desired digital filter threshold, VDF (

V), is

set by calculating the value stored in Digital Filter EE

0x52.

Is: The digital filter threshold, VDF (

V), is set by the

value stored in Digital Filter EE 0x52.

Pack capacity storage

Was: Pack capacity is programmed in mAh units to Pack

Capacity in EE 0x3a0x3b and Last Measured Discharge

in EE 0x380x39.

Is: Pack capacity in mAh units is stored in Pack

Capacity EE 0x3a0x3b.

Last Measured Discharge initial

value storage

Was:

Is: The initial value for Last Measured Discharge in mAh

is stored in EE 0x380x39.

bq2060

EDV compensation

Was: If EDV compensation is enabled, the bq2060

calculates battery voltage to determine EDV0, EDV1,

EDV2 as a function of EDV, battery capacity,

temperature, and discharge load

Is: If EDV compensation is enabled, the bq2060

calculates battery voltage to determine EDV0, EDV1,

and EDV2 thresholds as a function of battery capacity,

temperature, and discharge load.

equation term definition

Was: C is 0%, 3%, or Battery Low % for EDV0, EDV1,
and EDV2, respectively and C0 is the capacity related
EDV adjustment factors.
Is: C (0%, 3%, or Battery Low % for EDV0, EDV1, and
EDV2, respectively) and C0 are the capacity related
EDV adjustment factors.

Self-discharge rate

Was: Self

Discharge Rate

æ
è

ö
ø

52.73

%PERDAY

Is: Self

Discharge Rate

æ
è

ö
ø

256 -

52.73

%PERDAY

Temperature threshold equation

Was: MaxT

é
ë
ê

ù
û
ú

Int

MAXTEMP

1.6

0 5

Is: MaxT

é
ë
ê

ù
û
ú

MAXTEMP

1.6

CSYNC bit = 1

Was: The bq2060 sets update RM with a programmed
percentage of FCC.
Is: The bq2060 updates RM with a programmed
percentage of FCC at a valid charge termination.

CEDV

Was: If reset, the bq2060 uses the values . . .

Is: If reset, the bq2060 uses the fixed values . . .

CPE bit = 0

Was: No PEC byte on alarm warning to charger

Is: No PEC byte on broadcasts to charger

CPE bit = 1

Was: PEC byte on alarm warning to charger

Is: PEC byte on broadcasts to charger

ADC Offset

Was: adjusts the ADC offset
Is: adjusts the ADC reading

ADC Offset

Was: ADC Offset is typically set between -10 and 10.

Is: ADC Offset is typically set between -20 and 20.

VFC

Was: to calibrate the coulomb counting measurement for
system errors and sense resistor error
Is: to calibrate the coulomb counting measurement for
VFC gain errors and sense resistor tolerance

VFC

Was: opposite in sign as

Is: opposite in sign to

Extensive changes in DC Electrical

Characteristics table

Was: SLUS035C version

Is: SLUS035D version

VFC Characteristics table V

SROS

minimum/typical/maximum

Was: -300/-50/250

Is: -250/-50/250

VFC Characteristics

Was: V

= 3.13.5V

Is: V

= 3.13.6V

bq2060

REG Characteristics

Was: V

= 3.5V (max)

Is: V

= 3.6V (max)

VFC Characteristics table RM

VCO

conditions

Was: V

= 3.5V

Is: V

= 3.3V

VFC Characteristics table Note

Was: Note: RM

TCO

total deviation is from the gain at

25°C.
Is: Note: RM

TCO

total deviation is from the nominal gain

at 25°C.

REG Characteristics table title

Was: REG Characteristics

Is: REG Characteristics (T

OPR

= -2070

SMBus AC Specifications table

title

Was: SMBus AC Specifications (T

= T

OPR

, 2.9V < V

3.7V unless otherwise noted)
Is: SMBus AC Specifications (V

= 2.73.7V, T

OPR

-2070

C, Unless Otherwise Noted)

HDQ16 AC Specifications table
title

Was: HDQ16 AC Specifications (T

= T

OPR

, 2.9V < V

3.7V unless otherwise noted)
Is: HDQ16 AC Specifications (V

= 2.73.7V, T

OPR

-2070

C, Unless Otherwise Noted)

HDQ16 AC Specifications table

minimum

Was: 90

Is: 100

HDQ16 AC Specifications table

RSPS

minimum

Was: 320

Is: 190

HDQ16 AC Specifications table

RSPS

maximum

Was: -

Is: 320ms

Replace package diagram and
Ordering Information Package
Option with SS = 28-pin SSOP
(DBQ)

Was: SLUS035C version

Is: SLUS035D version

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Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: BQ2060

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: BQ2060