Document Outline
- FEATURES
- APPLICATIONS
- DESCRIPTION
- PIN CONFIGURATION
- QUICK REFERENCE DATA
- ORDERING INFORMATION
- FUNCTIONAL DIAGRAM
- IEC LOGIC SYMBOL
- PIN DESCRIPTION
- Power On Reset.
- Power-on sensing.
- Start-up with low battery voltage.
- Charge mode.
- Trickle charge mode.
- Discharge mode.
- Charge/Discharge mode.
- Self-discharge mode.
- LED mode select.
- Low indication.
- Alarm indication.
- Scan test mode.
- Remaining energy indication.
- Output drivers EN and EN.
- RECOMMENDED OPERATING CONDITIONS
- ABSOLUTE MAXIMUM RATINGS
- DC ELECTRICAL CHARACTERISTICS
- AC CHARACTERISTICS
- APPLICATION INFORMATION
- Oscillator.
- External components range
- Charge discharge times
- LED frequency
- MOLLI pulse duration
- Timing accuracy.
- Influence of Resistor value.
- Influence of supply voltage
- SPREAD-CAUSING FACTORS
- Error free operation, even under extreme conditions.
- Synchronous logic and bistable POR.
- Data retention.
- Debounce circuitry on DIS input.
- Schmitt trigger on PWRS (power sense) input.
- Special oscillator security to prevent any malfunction.
- Remaining energy indication
- PACKAGE OUTLINES
- SOT38-4
- SOT109-1
- SOT338-1
- SOT403-1
- Data sheet status
- Definitions
- Disclaimers
Philips
Semiconductors
74LV4799
Timer for NiCd and NiMH chargers
Product specification
Supersedes data of 1998 Apr 07
IC24 Data Handbook
1998 Apr 20
INTEGRATED CIRCUITS
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
2
1998 Apr 20
853-2058 19258
FEATURES
Wide supply voltage range of 0.9 V to 6 V allows 1 to 4-cell
applications
10 V allowed on special inputs
Supports virtually all battery chargers, including switched-mode
power supplies
On-chip timer calculates the actual capacity of the battery by
measuring the charger time, discharge time and self-discharge time
Automatic switch-over to trickle charge after completion of the
charge time
Can be adjusted for use with different types of batteries:
Charge time: 4 to 16 hours
Discharge time: 15 minutes to 4.7 hours
Self-discharge time: 50 to 100 days
Battery status indication included:
LED output for charging/full indication
MOLLI output for battery-low indication
LED mode select allows two different methods of indication
Automatic power-ON reset
Low-power consumption
Requires only a few peripheral components
Very accurate on-chip oscillator
Scan test facilities included
I
CC
category: non-standard.
APPLICATIONS
Time-controlled NiCd and NiMH low-current chargers
Domestic appliances such as rechargeable battery shavers,
electric toothbrushes etc.
Portable equipment such as notebook PCs, laptop PCs, camera
flash units etc.
Personal communications like cordless telephones, personal
mobile radios, pagers, etc.
DESCRIPTION
The 74LV4799 is a low-voltage Si-gate CMOS control IC for battery
management. It consists of:
17-stage divider
10-stage up/down counter
Control logic
Integrated precision oscillator (using external timing components)
Automatic power-ON reset
Scan test facilities
Battery charging/full indication output (LED)
Battery-low indication output (MOLLI)
Open-drain-N outputs for driving the load transistor
Battery management with the 74LV4799 is based on the principle of
time measurement. It measures the charge time, discharge time and
self-discharge time by means of a very accurate on-chip oscillator, a
divider and an up/down counter.
PIN CONFIGURATION
SV01643
1
2
3
4
5
6
LED
EN
EN
V
in
PWRS
MOLLI/SCO
V
CC
SCI
SCAN
16
15
14
13
12
11
7
8
GND
R
C
DIS
10
9
SEL
I
OSC
R
S
R
D
QUICK REFERENCE DATA
GND = 0V; T
amb
= 25
C
SYMBOL
PARAMETER
CONDITIONS
TYPICAL
TYPICAL
TYPICAL
UNIT
V
CC
DC supply voltage
0.9
6.0
V
I
CC
Operating supply current
V
CC
= 3.3V; self-discharge mode;
R
s
= 100 k
W
;
C
1
= 220nF
36
A
D
f
Oscillator frequency tolerance
V
CC
= 1 to 6 V
7
%
ORDERING INFORMATION
PACKAGES
TEMPERATURE RANGE
OUTSIDE NORTH AMERICA
NORTH AMERICA
CODE
16-Pin Plastic DIL
0
C to +70
C
74LV4799 N
74LV4799 N
SOT38-4
16-Pin Plastic SO
0
C to +70
C
74LV4799 D
74LV4799 D
SOT109-1
16-Pin Plastic SSOP Type II
0
C to +70
C
74LV4799 DB
74LV4799 DB
SOT338-1
16-Pin Plastic TSSOP Type I
0
C to +70
C
74LV4799 PW
74LV4799PW DH
SOT403-1
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
3
FUNCTIONAL DIAGRAM
SV01644
OSCILLATOR
CP
GND
GND
MOLLI/SCO
LED
EN
EN
GND
IOSC
RC
RD
RS
13
15
14
5
9
7
SCI
SCAN
PWRS
DIS
SEL
CP
3STAGE
DIVIDER
514 STAGE
DIVIDER
POWERON
RESET
CONTROL LOGIC
10STAGE
UP/DOWN
COUNTER
VCC
4
10
11
1
6
3
Vin
2
12
GND
GND
GND
GND
IEC LOGIC SYMBOL
SV01645
IOSC
RS
RD
DIS
RC
SCI
SCO
MOLLI
EN
4
2
3
6
16
8
1
LED
0V
U+[2]
U+[1]
1
SCAN/Z1
PWRS
SEL
CT=0
G
I=0
F
BATT. TIMER
13
12
11
10
9
15
14
5
7
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
4
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
1
LED
LED driver output pin (active LOW)
2
EN
Enable output (active HIGH)
3
EN
Enable output (active LOW)
4
V
in
External power input
5
PWRS
Power sense input
6
MOLLI/SCO
More-or-less-low-indication output (active LOW)/scan test output
7
SEL
LED mode select input
8
GND
Ground (0 V)
9
DIS
Discharge input (active LOW)
10
R
C
External resistor pin 3-State oscillator output (charge)
11
R
D
External resistor pin 3-State output (discharge)
12
R
S
External resistor pin 3-State output (self-discharge)
13
I
OSC
Oscillator input
14
SCAN
Scan test mode select input (active HIGH)
15
SCI
Scan test input
16
V
CC
Positive supply voltage
Power On Reset.
An automatic Power On Reset initiates the IC when the battery is
discharged and power is connected to the circuit. The initial
condition is the charge mode in which the counter is reset and
counts from zero up to maximum. At start up, the battery therefore
always receives a full charge cycle. When a partially charged battery
is inserted, it may be over-charged during the first cycle. To guard
against this, simply replace the resistor at the R
C
pin with an NTC
type which is in good thermal contact with the battery. If the
temperature of the battery increases, the frequency of the oscillator
also increases to quickly reach a counter full indication and
switch-over to trickle charge. With a battery that is almost
completely discharged, the POR input can also be activated during
discharge or self-discharge. The counter will then be reset to zero.
This is a correct action while returning to the initial condition.
Power-on sensing.
Because this IC supports virtually all battery chargers, the PWRS input
has a broad input frequency spectrum (active HIGH to 100 kHz). A
pull-down circuit at the PWRS input allows detection of the open state
which corresponds to an inactive charger. A HIGH level on the PWRS
input, or an AC signal up to 100 kHz, enables the charge mode.
Start-up with low battery voltage.
Good start-up, even with an un-charged battery, is assured by using
the V
IN
input. The voltage on the V
IN
input biases the external
bipolar transistors at the EN or EN output, even if the IC is not yet
functioning. After the battery has received sufficient charge, the
internal control logic takes over control of the EN and EN outputs.
Charge mode.
This mode is selected when PWRS is active (HIGH or pulsed) and
the discharge input DIS is HIGH. The EN output is HIGH, and the
EN output is LOW initiating continuous charge of the battery. The
counter then counts from the zero state up to the maximum value.
The clock frequency is determined by the external capacitor and
resistor connected to the R
C
output. The counter stops when it
reaches its maximum value and the EN and EN outputs switch over
from the continuous charge to the trickle charge mode.
Trickle charge mode.
At the maximum counter value, it is assumed that the battery is fully
charged. The counter stops and remains on this maximum value.
The EN and EN outputs switch over from the continues charge to
the trickle charge mode. In the trickle charge mode, the average
charge current is reduced to only compensate the self-discharge of
the battery by using the dedicated duty cycle control. The control is
dedicated because it adjusts the duty cycle in inverse proportion to
the load current, resulting in a fixed charger current irrespective of
the kind of charger (e.g. 4-hour or 16-hour charger). In the trickle
charge mode, the oscillator circuitry alternately generates 4 periods
of R
C
-C1 time-constant, and 3 periods of the R
S
-C1 time-constant
(See Figure 1).
Discharge mode.
The discharge input (DIS) is used to detect the discharge of the
battery. If DIS is LOW, the counter counts down. The clock
frequency is determined by the external capacitor and resistor at the
R
D
output. If PWRS is inactive (LOW or open), the EN output is
LOW, and the EN output is in the high impedance OFF-state (no
charge of the battery). This is called the discharge mode. If PWRS is
active, the circuit is in the charge/discharge mode.
Charge/Discharge mode.
If DIS is LOW and PWRS is active (HIGH or pulsed), the circuit is in
the charge/discharge mode. The counter counts down. The clock
frequency is determined by the external capacitor and resistor tied
at the R
D
output. The EN output is HIGH, and the EN output is LOW
initiating continuous charge of the battery. The battery is therefore
charged and discharged at the same instant, thereby maintaining a
better load condition of the battery.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
5
Self-discharge mode.
If DIS is HIGH and PWRS is inactive (LOW or open), the battery is
being neither charged nor discharged. The circuit is in the
self-discharge mode. This mode represents the battery leakage
(self-discharge). The counter counts down. The clock frequency is
determined by the external capacitor and resistor at the R
S
output.
When the counter reaches the zero state, it stops.
LED mode select.
The LED output drives a battery status LED which indicates the
charge/full status of the battery. For optimum flexibility, two modes of
operation are built-in.
Mode 1: If SEL is LOW, the LED output is active LOW in the
charge mode, and the LED blinks with a frequency of
about 1 Hz during trickle charge.
Mode 2: If SEL is HIGH or open, the LED output blinks with a
frequency of about 0.25 Hz in the charge mode, and is
active LOW during trickle charge. In the discharge or
self-discharge mode, the LED output is open except
when PWRS is active (HIGH or pulsed). Then, the
battery is charging and discharging simultaneously.
Although the discharge mode is dominant, the LED
output is active when PWRS is also active.
NOTE: The blink frequency depends on the oscillator frequency.
(See application information)
Low indication.
As part of the user interface, the MOLLI output shows when the
battery needs to be charged. MOLLI stands for More Or Less Low
Indication (active LOW). The function is as follows: In the discharge
mode, (DIS is active LOW), the counter counts down and, when it
reaches the zero state, it stops. If DIS is switched HIGH, the MOLLI
output gives an output signal of four periods of about one second,
with a 50% duty cycle. This can be used to activate a buzzer. The
MOLLI output signal of four periods will be interrupted as soon as
PWRS is activated.
Alarm indication.
If an almost completely discharged battery is connected to the
charger, it may not be noticed by the user if the load switch is still
on. To prevent damaging the battery, an alarm signal on the LED
output will alert the user to switch off the load. The alarm signal is
easily recognized, because the LED output will blink at a higher
frequency than normal (about 5 Hz instead of 1 Hz). This alarm
indication is only active if the SEL input is HIGH or open. If the SEL
input is LOW, no alarm indication is present, because in many
applications simultaneous charging and discharging is quite
acceptable. (See charge/discharge mode)
Scan test mode.
If the SCAN input (pin 14) is made active HIGH, the circuit is in the
test mode. The tester clock is connected to the I
OSC
pin (pin 13). In
the scan mode, the onchip oscillator is bypassed to allow rapid
testing of the divider/counter. The scan test patterns are available on
request. The scan test data is entered serially through the SCI input
(pin 15). The scan out data is present on the MOLLI/SCO output
(pin 6), which then acts as a scan output.
Remaining energy indication.
The scan test facility can be used as a remaining energy indication
because the value of the counter can be read out at the scan output
(MOLLI/SCO). This is done by briefly interrupting the normal mode
of operation, putting the circuit in the scan mode, and reading out
the counter value. The circuit then reverts to the normal mode. This
only works correctly with the MOLLI/SCO output and SCI input
linked (round coupled loop) and with exactly 49 clock pulses applied
to the I
OSC
input.
The serial scan-out data is available on the MOLLI/SCO output. The
value of the counter can be decoded by reading the correct bits.
Details are given later in the section "Application information".
Output drivers EN and EN.
In one-cell battery (low-voltage) applications, the drive from the
ENABLE output (EN) is insufficient to provide the base current directly
for the external bipolar PNP regulator transistor. The inverse signal has
therefore been made available at the ENABLE output (EN) to drive an
extra bipolar NPN transistor that can provide the base current for the
bipolar PNP regulator transistor as shown in Figure 2.
FUNCTION TABLE 1
OPERATING
INPUTS
OUTPUTS
DIVIDER/COUNTER
OPERATING
MODES
PWRS
V
IN
DIS
EN
EN
R
C
R
D
R
S
MODE
VALUE
Charge
H or
H
H
H
L
Z
Z
Count up 22 sections
<
max
Trickle charge
H or
H
H
Z
Stop
max
Charge/discharge
H or
H
L
H
L
Z
Z
Count down 18 sections
min
Discharge
L or open
X
L
L
Z
Z
Z
Count down 18 sections
min
Self-discharge
L or open
X
H
L
Z
Z
Z
Count down 27 sections
min
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
6
FUNCTION TABLE 2
STATUS
INPUTS
OUTPUTS
COUNTER
STATUS
INDICATION
PWRS
DIS
SEL
(1)
LED
MOLLI
MODE
VALUE
Charge
H or
H
L
L
Z
Count up
<
max
Charge
H or
H
H or open
Z
Count up
<
max
Charge/discharge
H or
L
L
L
Z
Count down
min
Trickle charge
H or
H
L
Z
Stop
max
Trickle charge
H or
H
H or open
L
Z
Stop
max
Discharge
L or open
L
X
Z
Z
Count down
>
min
Self-discharge
L or open
H
X
Z
Z
Count down
>
min
Low
L or open
X
Z
Stop
min
Low
X
Z
Z
(2)
Count up
min
Alarm
H or
L
H or open
Z
Count down
min
NOTES:
1. Don't change SEL during operation.
2. The MOLLI function will be interrupted as soon as PWRS is activated.
H
= HIGH voltage level
L
= LOW voltage level
Z
= high impedance OFF-state
X
= don't care
= pulsed (H/L)
= pulsed (Z/L)
= 4 periods of about one second (Z/L)
= LOW-to-HIGH level transition
SV01646
R
C
Zstate
Zstate
Zstate
Zstate
Zstate
R
S
I
OSC
EN
EN
Operation in the trickle charge mode. The duration of the R
C
cycle determines the duty cycle of the enable outputs (EN and EN), allowing a dedicated
control. The average trickle charge current will compensate for the self-discharge, independent of the charge current.
Figure 1. Trickle charge mode characteristics.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
7
RECOMMENDED OPERATING CONDITIONS
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
V
CC
DC supply voltage
See Note 1
0.9
1.2
6
V
V
I
Input voltage pins 4, 5, and 9
Input voltage pins 7, 13, 14, and 15
0
0
10
V
CC
V
V
O
Output voltage pins 10, 11, and 12
Output voltage pins 1, 2, 3, and 6
0
0
V
CC
10
V
T
amb
Operating ambient temperature range in free air
See DC and AC
characteristics per device
0
+70
C
Input rise and fall times pin 5
10
ms
t
r
, t
f
Input rise and fall times pins 7, 14 and 15
V
CC
= 1.0V; V
I
= 1.0V
V
CC
= 2.0V; V
I
= 2.0V
V
CC
= 3.0V; V
I
= 4.5V
V
CC
= 3.6V; V
I
= 6.0V
500
200
100
50
ns
Input rise and fall times pin 9
2
s
NOTE:
1. Single sided input protection applied on pins 4, 5, and 9.
ABSOLUTE MAXIMUM RATINGS
2, 3
In accordance with the Absolute Maximum Rating System (IEC 134).
Voltages are referenced to GND (ground = 0 V).
SYMBOL
PARAMETER
CONDITIONS
MIN
MAX
UNIT
V
CC
DC supply voltage
0.5
+7.0
V
DC input diode current pins 4, 5 and 9
V
I
<
0.5 or V
I
>
12 V
20
I
IK
DC input diode current pins 7, 13, 14 and 15
V
I
<
0.5 or V
I
>
V
CC
+ 0.5 V
+20
mA
NON repetitive peak DC input diode current pin 9
V
I
>
10 V and t
<
10
m
s; see note 1
10
V
I
DC input voltage range pins 4, 5 and 9
0.5
+12
V
V
I
DC input voltage range pins 7, 13, 14 and 15
0.5
V
CC
+ 0.5
V
I
OK
DC output diode current pins 1, 2, 3 and 6
V
O
<
0.5 V
20
mA
I
O
DC output sink current pins 1, 2, 3 and 6
V
O
>
0 V
25
mA
I
OK
DC output diode current pins 10, 11 and 12
V
O
<
0.5 or V
O
>
V
CC
+ 0.5 V
20
mA
I
O
DC output sink or source current pins 10, 11 and 12
0.5 V
<
V
O
<
V
CC
+ 0.5 V
25
mA
I
GND
, I
CC
DC GND or V
CC
current
50
mA
T
stg
Storage temperature range
65
+150
C
Power dissipation per package
for temperature range: 40 to +125
C
P
t t
Power dissi ation er ackage
Plastic DIL
for tem erature range: 40 to +125 C
above + 70
C derate linearly with 12 mW/K
750
mW
P
tot
Plastic mini-pack (SO)
Pl
ti
h i k
i i
k (SSOP
d TSSOP)
y
above + 70
C derate linearly with 8 mW/K
b
60
C d
t li
l
ith 5 5
W/K
500
400
mW
Plastic shrink mini-pack (SSOP and TSSOP)
above + 60
C derate linearly with 5.5 mW/K
400
NOTES:
1. In applications where a motor is present, the input voltage may exceed the maximum V
I
, level of 10 V at the DIS input for a very short period
when the motor is switched off.
2. Stresses beyond those listed may cause permanent damage to the device. These are stress ratings only and functional operation of the
device at these or any other conditions beyond those under "recommended operating conditions" is not implied. Exposure to absolute
maximum rated conditions for extended periods may affect device reliability.
3. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
8
DC ELECTRICAL CHARACTERISTICS
Over recommended operating conditions.
Voltages are referenced to GND (ground = 0 V).
LIMITS
SYMBOL
PARAMETER
TEST CONDITIONS
+25
C
0
C to +70
C
UNIT
MIN
TYP
MAX
MIN
MAX
V
CC
= 1.0 V
0.8
0.5
0.8
V
IH
HIGH level Input voltage
V
CC
= 4.5 V
3.6
2.4
3.6
V
V
CC
= 6.0 V
4.8
3.2
4.8
V
CC
= 1.0 V
0.5
0.2
0.2
V
IL
LOW level Input voltage
V
CC
= 4.5 V
2.1
0.9
0.9
V
V
CC
= 6.0 V
2.8
1.2
1.2
HIGH level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
= 190
A
0.90
0.96
0.89
V
OH
g
R
C
, R
D
outputs
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
= 6.1mA
5.73
5.84
5.66
V
V
OH
HIGH level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
=24
A
0.90
0.96
0.89
V
g
R
S
output
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
=760
A
5.73
5.84
5.66
LOW level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
= 190
A
0.04
0.10
0.11
g
R
C
, R
D
outputs
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
= 6.1mA
0.16
0.26
0.33
LOW level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
=24
A
0.04
0.10
0.11
g
R
S
output
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
=760
A
0.16
0.26
0.33
LOW level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
= 220
A
0.04
0.10
0.11
g
MOLLI, LED outputs
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
= 7.4mA
0.17
0.26
0.33
V
OL
LOW level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
=360
A;
pin 4 open
0.04
0.10
0.11
V
g
EN output
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
=13.0mA;
pin 4 open
0.17
0.26
0.33
LOW level output voltage;
EN output
V
CC
= 1.3 V; V
I
= V
IH
or V
IL;
pin 4 = 10 V
1
0.12
0.35
0.40
LOW level output voltage;
V
CC
= 1.0 V; V
I
= V
IH
or V
IL;
I
O
=140
A;
pin 4 HIGH
0.04
0.10
0.11
g
EN output
V
CC
= 6.0 V; V
I
= V
IH
or V
IL;
I
O
=5.0mA;
pin 4 HIGH
0.17
0.26
0.33
V
CC
POR level
active inactive
0.25
0.65
0.9
V
I
CC
Quiescent supply current
V
CC
= 6.0 V; V
I
= V
CC
or GND;
pins 5, 14, and 15 at GND;
pins 7 and 9 at V
CC
2
34
50
400
A
Input leakage current
pins 4 and 9
V
CC
= 1.0 V; V
I
= 10 V
500
nA
Input leakage current
pins 14 and15
V
CC
= 6.0 V; V
I
= V
CC
or GND
100
nA
I
I
Pull-up current pin 7
V
CC
= 1.0 V; V
I
= GND
0.5
2.4
10
Pull-u current in 7
V
CC
= 6.0 V; V
I
= GND
0.5
2.4
10
A
Pull-down current pin 5
V
CC
= 1.0 V; V
I
= V
CC
0.5
2.4
10
A
Pull-down current in 5
V
CC
= 6.0 V; V
I
= V
CC
0.5
2.4
10
I
OFF-state current
pin 1, 3, and 6
V
CC
= 6.0 V; V
I
= V
IH
or V
IL
; V
O
= 10 V
500
nA
I
OZH
OFF-state current pin 2
V
CC
= 6.0 V; V
O
= 6 V; V
in
= open
100
nA
OFF-state current pin 3
V
CC
= 6.0 V; V
I
= V
IH
or V
IL
; V
O
= 6 V
100
I
OZ
OFF-state current
pins 10, 11, and 12
V
CC
= 6.0 V; V
I
= V
IH
or V
IL
;
V
O
= V
CC
or GND
100
nA
NOTE:
1. This item guarantees that an external bipolar NPN-transistor can be switched off by the EN output.
2. Oscillator disabled. This can be done by I
OC
= HIGH or LOW.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
9
AC CHARACTERISTICS
GND = 0V; t
r
= t
f
2.5ns; C
L
= 50pF
TEST CONDITIONS
T
amb
(
C)
SYMBOL
PARAMETER
TEST CONDITIONS
+25
0 to +70
UNIT
V
CC
(V)
MIN
TYP
MAX
MIN
MAX
f
Oscillator frequency spread
1.0
Any resistor or capacitor according to
11
4
+3
%
f
Oscillator frequency s read
6.0
y
g
the application information, see note 1
9
2
+5
%
LED
Duty factor at pin 1
1.0
See Note 2
50
%
LED
Duty factor at in 1
6.0
See Note 2
50
%
MOLLI
Duty factor at pin 6
1.0
See Note 3
50
%
MOLLI
Duty factor at in 6
6.0
See Note 3
50
%
t
d b
Debounce suppression at pin 9
1.0
67
ms
t
deb
Debounce su
ression at in 9
6.0
65
ms
f
i(
)
Maximum frequency at power
1.0
100
kHz
f
i(max)
q
y
sense input
6.0
100
kHz
f
i( i )
Minimum frequency at power
1.0
50
Hz
f
i(min)
q
y
sense input
6.0
50
Hz
NOTES:
1. The oscillator frequency can be calculated by: f
+
0.36
R
C1
2. During blinking.
3. An output signal of four periods will appear in case of discharged batteries and DIS is switched HIGH.
APPLICATION INFORMATION
Oscillator.
The frequency will be determined by the external components R
C
, R
D
, R
S
, and C
1
. The frequencies can be calculated by the following
expressions: f
+
0.36
R
C
C1
; f
+
0.36
R
D
C1
; f
+
0.36
R
S
C1
.
R
C
and C1 determine the charge time.
R
D
and C1 determine the discharge time.
R
S
and C1 determine the self-charge time.
The charge, discharge and self-discharge times can be calculated as follows:
Charge time
+
2
22
f
C
; Discharge time
+
2
18
f
D
; Self-discharge time
+
2
27
f
S
In the trickle charge mode, the average charge current will be reduced by a factor:
1
1
)
3 x R
S
4 x R
C
External components range
TEST CONDITIONS
T
amb
(
C)
SYMBOL
PARAMETER
TEST CONDITIONS
+25
UNIT
V
CC
(V)
V
1
OTHER
MIN
TYP
MAX
1.0
5.360
100
k
W
R
C
/R
D
Resistor range
2.0
C1 = 0 22
F
1.150
100
k
W
R
C
/R
D
Resistor range
4.5
C1 = 0.22
F
0.562
100
k
W
6.0
0.511
100
k
W
1.0
42.20
825
k
W
R
S
Resistor range
2.0
C1 = 0 22
F
9.09
825
k
W
R
S
Resistor range
4.5
C1 = 0.22
F
4.22
825
k
W
6.0
3.32
825
k
W
1.0
no limit
pF
C1
Capacitor range
2.0
no limit
F
C1
Ca acitor range
4.5
no limit
pF
6.0
no limit
F
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
10
Charge discharge times
PARAMETER
TIME RANGE
CONDITIONS
Charge time
4 hours to 16 hours
Components ranges are within the values
Discharge time
15 minutes to to 4.7 hours
Components ranges are within the values
given in Section "External components range"
Self-discharge time
50 days to 100 days
given in Section External com onents range
LED frequency
The frequency of the LED output (pin1) is determined by the oscillator frequency.
Three modes of operation, each with its own frequency, are possible.
f
D
32
1
8
f
C
)
6
f
S
f
C
256
Mode
SEL
LED frequency
Charge
Trickle charge
Alarm
H or open
L
H
MOLLI pulse duration
The MOLLI output gives an output signal of four periods with a 50%
duty cycle. The duration of one period is determined by: 16/f
s
Timing accuracy.
The timing accuracy depends on the accuracy of the onchip
oscillator and on the external R and C components. The inaccuracy
of the onchip oscillator is specified as maximum +/7%. In most
cases the actual inaccuracy will be significantly lower. This depends
on the supply voltage as well as the value of the external
components.
Influence of Resistor value.
Low resistor values cause some spread because the RC
combination is biased by a 3State pushpull output. The spread of
the R
on
of the pushpull stage will contribute to the frequency
spread. When highvalue resistors are used, any possible output
leakage of the notselected 3State outputs will cause a frequency
deviation. For these reasons, the resistor values must be within the
specified ranges.
Influence of supply voltage
The trip levels of the oscillator are fixed at 20% and 80% of V
cc
. At
higher supply voltages the spread of the trip levels decreases in
greater proportion because the offset voltage remains constant, and
the propagation delay decreases. Furthermore, the R
on
values of
the pushpull driving stage decrease at higher voltages.
SPREAD-CAUSING FACTORS
SYMBOL
PARAMETER
V
CC
T
amb
(
C)
UNIT
SYMBOL
PARAMETER
CC
(V)
MIN
TYP
MAX
UNIT
V
ff
Offset voltage
1.0
7
mV
V
off
Offset voltage
6.0
7
mV
t
P
Propagation delay
1.0
22
m
s
t
P
Pro agation delay
6.0
5.5
m
s
R
ON
P-channel resistance R
C
R
D
outputs
1.0
170
W
R
ON
P-channel resistance R
C
, R
D
out uts
6.0
25
W
R
ON
N-channel resistance R
C
R
D
outputs
1.0
250
W
R
ON
N-channel resistance R
C
, R
D
out uts
6.0
35
W
R
ON
P-channel resistance R
S
output
1.0
1300
W
R
ON
P-channel resistance R
S
out ut
6.0
180
W
R
ON
N-channel resistance R
S
output
1.0
1300
W
R
ON
N-channel resistance R
S
out ut
6.0
180
W
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
11
Error free operation, even under extreme conditions.
Several measures are taken in the circuit design to ensure
errorfree operation, even with very low supply voltages. Moreover,
the circuit has been made very insensitive to the effects of external
fields. The measures taken during the design are:
Use of synchronous logic
Bistable POR instead of monostable POR
Data retention assured below a supply voltage of 0.9 V.
Debounce circuitry on DIS input (maximum expected debounce
time = 10 ms)
Schmitt trigger on PWRS (power sense) input and on DIS input
Special oscillator security to prevent any malfunction.
Synchronous logic and bistable POR.
Use of synchronous logic results in much lower sensitivity to spikes
on input pins. The POR is adapted to fit well into a synchronous
environment. An increasing supply voltage sets the POR. The POR
output signal is routed to the control logic and divider/counter. it is
synchronized with the onchip clock. After all flipflops are reset, a
reset acknowledge signal is generated which resets the POR. This
method ensures that the POR signal is acknowledged in all cases,
even at very low voltages.
Data retention.
The circuit may be used in an application where an electric motor is
present. When the motor is switched on, it will disturb the supply
voltage for a short period. The POR level is set at such a level that,
even with very low supply voltages, the POR will not respond during
motor switch on. The flipflops will retain their data during the supply
voltage disturbance because of the inherent data retention of any
CMOS gate. However, when the battery is almost completely
discharged and the motor switch is activated, the dip on the supply
voltage line can be too large. The retention of the POR is therefore
made deliberately worse than that of the internal flipfops. The POR
will therefore respond long before the flipflops will loose their data.
This results in a proper start condition for a new charge cycle.
Debounce circuitry on DIS input.
A discharge cycle is activated by a switch. To protect the circuit from
any bounce of the switch contacts, debounce circuitry is provided
at the DIS input. The circuitry allows a switch debounce time of
max. 10 ms.
Schmitt trigger on PWRS (power sense) input.
The PWRS input can be corrupted by high transients due to
disturbances on the mains supply. To suppress any false triggering,
the PWRS input is provided with a Schmitttrigger. However, for
some applications, it is advisable to connect a lowvalue capacitor
(150 pF min.) between the PWRS input and GND.
Special oscillator security to prevent any malfunction.
The excellent performance of the oscillator is achieved by using
linear opamp techniques. The oscillator consists of an internal
reference, two comparators and a latch. Care was taken to design a
very reliable oscillator even with a supply voltage below 0.9 V. If one
of the comparators ceases to operate with a supply voltage below
0.9 V, the latch will not be corrupted. Priority was given to stop the
oscillator rather than allow uncontrolled oscillation.
All these measures result in reliable 1-cell to 4-cell battery charge
management.
Remaining energy indication:
The scan test facility can be used as a remaining energy indication
because the value of the counter can be readout at the scan output
(MOLLI/SCO). This is achieved by briefly interrupting the normal
mode of operation, putting the circuit in the scan mode
(pin 14 = HIGH), and readingout of the counter value. The circuit is
then returned to the normal mode (pin 14 = LOW or open).
Readout procedure: The contents of the counter flipflops can be
readout in the scan mode. To ensure that there is no disturbance of
the circuit function, it is essential to either create a round coupled loop
by linking the MOLLI/SCO output (pin 6) directly to the SCI input
pin 15), or to shiftin the serial data of the scan line at the SCI input
after completion of the read out cycle. 49 clock pulses are needed on
the Iosc input (pin 13) to shiftout the contents of the whole scan line.
The mostsignificant bit of the counter will appear at the MOLLI/SCO
output after the last clock pulse. The leastsignificant bit after the
penultimate clock pulse, etc. Selecting the last three or four bits will
yield sufficiently high accuracy to obtain the counter value which
represents the remaining energy of the battery.
SV01647
R C
SCI
SCAN
SEL
PWRS
LED
V in
EN
n.c.
EN
V CC
MOLLI
DIS
1
5
7
14
15
9
6
16
2
4
3
10
11
12
13
8
R D
R S
IOSC
R Z
LOAD
battery
buzzer
74LV4799
220 V
110 V
AC
mains
BC557
BYD13D
BZD23
BYD13D
BZD23
BYD13D
BYD13D
BC547
BC327/
BC636
BC557
Figure 2. Typical application of the low-voltage 74LV4799.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
12
SV01648
RC
GND
SEL
PWRS
100240 VAC
12/24 VDC
Vin
Vin
DRN
VAT
SRC
VIC
S2
S1
GND
C
VAC2
VAC1
PWR/LED
EN
VCC
EN
1.0 mH
33E
TR1
S
TR1
1E
2
2
10
1
F
DIS
LED
5
7
8
9
1
4
3
10
20
16
15
14
13
11
12
9
8
7
6
1
10
11
12
13
16
RD RS IOSC
LOAD
74LV4799
TEA1400
1
F
2
2
Figure 3. Application diagram of the 74LV4799 in combination with the high-voltage IC TEA1400.
SV01649
R C
SCI
SCAN
SEL
PWRS
V in
EN
EN
Q1
Q2
V CC
DIS
GND
LED
5
7
14
15
9
2
1
3
4
10
11
12
13
8
16
6
R D
R S IOSC
R Z
Z 1
L S
LOAD
battery
74LV4799
Option A: At V
CC > 2.0 V Q1 may
be directly biased by EN
Option B: At V
CC < 2.0 V add
an extra NPN transistor (Q2)
BYD13D
A
B
BYD13D
MOLLI/
SCO
Figure 4. Inductive loader, showing the two options A and B.
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
13
DIP16:
plastic dual in-line package; 16 leads (300 mil)
SOT38-4
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
14
SO16:
plastic small outline package; 16 leads; body width 3.9 mm
SOT109-1
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
15
SSOP16:
plastic shrink small outline package; 16 leads; body width 5.3 mm
SOT338-1
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
16
TSSOP16:
plastic thin shrink small outline package; 16 leads; body width 4.4 mm
SOT403-1
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
1998 Apr 20
17
NOTES
Philips Semiconductors
Product specification
74LV4799
Timer for NiCd and NiMH chargers
yyyy mmm dd
18
Definitions
Short-form specification -- The data in a short-form specification is extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Limiting values definition -- Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one
or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or
at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended
periods may affect device reliability.
Application information -- Applications that are described herein for any of these products are for illustrative purposes only. Philips
Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or
modification.
Disclaimers
Life support -- These products are not designed for use in life support appliances, devices or systems where malfunction of these products can
reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications
do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application.
Right to make changes -- Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard
cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless
otherwise specified.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 940883409
Telephone 800-234-7381
Copyright Philips Electronics North America Corporation 1998
All rights reserved. Printed in U.S.A.
print code
Date of release: 05-96
Document order number:
9397-750-04664
Philips
Semiconductors
Data sheet
status
Objective
specification
Preliminary
specification
Product
specification
Product
status
Development
Qualification
Production
Definition
[1]
This data sheet contains the design target or goal specifications for product development.
Specification may change in any manner without notice.
This data sheet contains preliminary data, and supplementary data will be published at a later date.
Philips Semiconductors reserves the right to make chages at any time without notice in order to
improve design and supply the best possible product.
This data sheet contains final specifications. Philips Semiconductors reserves the right to make
changes at any time without notice in order to improve design and supply the best possible product.
Data sheet status
[1]
Please consult the most recently issued datasheet before initiating or completing a design.
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