W83L785R

WINBOND H/W MONITORING IC FOR NOTEBOOK

1. GENERAL DESCRIPTION

W83L785R is a condensed product of W83L785R --- Winbond's most popular hardware monitoring IC
for notebook. Specifically designed for the graphic cards and notebook systems, W83L785R can be
used to monitor several critical hardware parameters of the system, including voltages, fan speeds,
and temperatures, which are very important for the system to work stably and properly.

An 8-bit analog-to-digital converter (ADC) was built inside W83L785R. The W83L785R can monitor 4
analog voltage inputs, 2 fan tachometer inputs, 2 remote temperature sensors. The remote
temperature sensing can be performed by thermistors, or 2N3904 NPN-type transistors, or connected
from Intel

Deschutes CPU thermal diode output. The W83L785R provides 2 PWM (pulse width

modulation) outputs for the fan speed control. Also the W83L785R provides: SMI#, OVT#, Temp
fault, GPIO signals for system protection events; I

serial bus interface. W83L785R also provides

4 pure GPIO and 7 multifunctional GPIO pins, and powered by 3.3V.

Through the application software or BIOS, the users can read all the monitored parameters of system
from time to time. And a pop-up warning can be also activated when the monitored item was out of
the proper/preset range. The application software could be Winbond's Hardware Doctor

, or Intel

LDCM (LanDesk Client Management), or other management application software. Also the users can
set up the upper and lower limits (alarm thresholds) of these monitored parameters and to activate
one programmable and maskable interrupts. For the spacing saving consideration of the Notebook
system, W83L785R is in the package of 209mil 20pins-SSOP.

W83L785R

Preliminary

Publication Release Date: Apr. 2001

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2. FEATURES

2.1 Monitoring Items

2 thermal inputs from remote thermistors or 2N3904 NPN-type transistors or Pentium

(Deschutes) thermal diode output

4 voltage inputs

--- typical for Vcore, +3.3V (Power), +2.5V, +1.5V

2 sets of PWM fan speed control

WATCHDOG comparison of all monitored values

Programmable hysteresis and setting points (alarm thresholds) for all monitored items

2.2 Actions Enabling

2 PWM (pulse width modulation) outputs for fan speed control

--- Total up to 2 sets of fan speed monitoring and controlling

Issue temperature fault signal as the temperature of the system/CPU exceeds its limit.

Issue SMI#, OVT#, GPIO and Temp. Fault signals to activate system protection

Warning signal pop-up in application software

2.3 General

serial bus interface

Intel

LDCM (DMI driver 2.0) support

Winbond hardware monitoring application software (Hardware Doctor

) support, for both

Windows 95/98 and Windows NT 4.0/5.0

Meet WfM 2.0 (Wired for Management) spec.

3.3V VCC operation

2.4 Package

20-pin SSOP (209mil)

W83L785R

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3. KEY SPECIFICATIONS

Voltage monitoring accuracy

1% (Max)

Monitoring Temperature Range and Accuracy

- 40

C to +120

C(Max)

Supply Voltage 2.7V ~ 5.5V

Operating Supply Current 2 mA typ.

Power Down Supply Current 20 uA typ.

ADC Resolution 8 Bits

4. PIN CONFIGURATION

SDA

VCC

CPUT1/PII1

VREF

+2.5VIN/GPIO14

CPUT2/PII2

GND

GPIO5

OVT#/GPIO8

SMI#/GPIO7

PWMOUT2

SCL

PWMOUT1

TEMP_FAULT/GPIO11

FANIN2/GPIO2

FANIN1/GPIO1

GPIO13

GPIO6

VCORE/GPIO16

+1.5V/GPIO15

W83L785R

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5. PIN DESCRIPTION

I/O

12t

- TTL level bi-directional pin with 12 mA source-sink capability,open drain output

I/O

12ts

- TTL level and schmitt trigger

OUT

- Output pin with 12 mA source-sink capability

AOUT - Output pin(Analog)

- Open-drain output pin with 12 mA sink capability

- TTL level input pin

- TTL level input pin and schmitt trigger

AIN - Input pin(Analog)

PIN NAME

PIN NO.

TYPE

DESCRIPTION

FANIN1 /
GPIO1

t s

I/OD

12ts

0V to +3.3V amplitude fan tachometer input.(Default) /
General purpose I/O function.
This multi-functional pin is programmable.

FANIN2 /
GPIO2

t s

OUT

1 2

0V to +3.3V amplitude fan tachometer input. (Default) /
General purpose I/O function.
This multi-functional pin is programmable.

PWMOUT1

Fan speed control PWM output. This pin is open-drain

PWMOUT2

Fan speed control PWM output. This pin is open-drain

GPIO5

I/OD

12ts

General purpose I/O function.

GPIO6

I/OD

12ts

General purpose I/O function.

SMI#/
GPIO7

I/OD

12ts

System Management Interrupt.
General purpose I/O function.
This multi-functional pin is programmable.

OVT#/
GPIO8

I/OD

12ts

Over temperature Shutdown Output.
General purpose I/O function.
This multi-functional pin is programmable.

SCL

t s

Serial Bus Clock.

SDA

I/OD

Serial Bus bi-directional Data.

TEMP_FAULT
GPIO11

1 2

I/OD

12ts

Active-Low output. This pin will be a logic LOW when the
temperature of the system or CPU exceeds its limit. (Default) /
General purpose I/O function.
This multi-functional pin is programmable.

GND

Ground

Ground.

W83L785R

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Pin Discription, continued

PIN NAME

PIN NO.

TYPE

DESCRIPTION

GPIO13

I/OD

12ts

General purpose I/O function. Default Open drain.

+2.5V/

GPIO14

AIN

I/OD

12ts

0V to 2.048V FSR Analog Inputs. (This pin is connected to the
+2.5V).

General purpose I/O function.

This multi-functional pin is programmable.

+1.5V/

GPIO15

AIN

I/OD

12ts

0V to 2.048V FSR Analog Inputs. (This pin is connected to the
+1.5V).

General purpose I/O function.

This multi-functional pin is programmable.

VCORE/

GPIO16

AIN

I/OD

12ts

0V to 2.048V FSR Analog Inputs. (This pin connected to
VCORE)

General purpose I/O function.

This multi-functional pin is programmable.

VREF

AOUT

Reference Voltage.

CPUT2 /

PII2

AIN

Thermistor terminal input.(Default) /

Pentium

II diode input.

This multi-functional pin is programmable.

CPUT1 /

PII1

AIN

Thermistor terminal input.(Default) /

Pentium

II diode input.

This multi-functional pin is programmable.

VCC

POWER

+3.3 VCC power supply input.

W83L785R

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6. FUNCTIONAL DESCRIPTION

6.1 General Description

The W83L785R provides most 4 analog positive inputs, 2 fan speed monitors, 2 sets for fan
PWM (Pulse Width Modulation) control, 2 remote thermal inputs from remote thermistors or 2N3904
transistors or Pentium

II (Deschutes) thermal diode outputs. W83L785R also provides software

power down this chip to save power, but I2C interface is still working. When W83L785 starts the
monitor function on the chip, the Watch Dog machine monitor every function and store the value to
registers. If the monitor value exceeds the limit value, the interrupt status will be set to 1.

6.2 Access Interface

The W83L785R provides I

C Serial Bus to read/write internal registers. In the W83L785R, the

I2C address defined value is 0101101.

6.2.1 The first serial bus access timing are shown as follow:

(a) Serial bus write to internal address register followed by the data byte

Start By

Master

Ack

785R

R/W

Ack

785R

SCL

SDA

Ack

784R

Stop

Master

SCL

SDA (Continued)

Frame 2

Internal Index Register Byte

(Continued)

Frame 3

Data Byte

Frame 1

Serial Bus Address Byte

Figure 1. Serial Bus Write to Internal Address Register followed by the Data Byte

Ack
by
785R

W83L785R

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(b) Serial bus read form internal address register followed by the data byte

Start By

Master

Ack

785R

R/W

Ack

785R

SCL

SDA

Ack

784R

Stop by
Master

SCL

SDA (Continued)

Frame 2

Internal Index Register Byte

(Continued)

Frame 4

Data Byte

Frame 1

Serial Bus Address Byte

Figure 2. Serial Bus read from Internal Address Register followed by the Data Byte

R/W

ack
by
785R

Frame 3

Serial Bus Byte

ack
by
785R

W83L785R

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6.3 Analog Inputs

The maximum input voltage of the analog pin is 2.048V because the 8-bit ADC has the 8mv LSB.
Actually, the application of the voltage monitoring would most often be connected to power suppliers.
The +1.5V voltage can directly connected to these analog inputs. The +2.5V and CPU VOCRE, the
inputs higher than 2.048V, should be reduced a factor with external resistors so as to obtain the input
range. As Figure 3 shows.

VIN0(VCORE)(Max2.048V)

+1.5V

Pin 15

Pin 14

Pin 20

VCC

+2.5Vin

8-bit ADC

with

8mV LSB

Typical Thermister
Connection

100K, 1%

RTHM

Pin 17

CPUT1

Pin 19

Positive Inputs

10K, 25 C

**The connections of CPUT2

is same as CPUT1

Pin 16

VREF

10K, 1%

200K, 1%

VIN1(Max2.048V)

VIN2

VIN3

Figure. 3.

6.3.1 Voltage Monitor input can not be over 2.048V :

The input voltage VIN1 or Vcore can be expressed as following equation:

VIN

. V

+2.5V

is +2.5V inputs.

The value of R1 and R2 can be selected to 100K Ohms and 200K Ohms, respectively, when the input
voltage is 2.5V. The node voltage of VIN3 can be subject to less than 2.048V for the maximum input
range of the 8-bit ADC. The pin 20 is connected to the power supply VCC with +3.3V. There are two
functions in this pin with 3.3V. The first function is to supply internal analog power of the W83L785R
and the second function is that this voltage with 3.3V is connected to internal serial resistors to
monitor the +3.3V voltage. The value of two serial resistors are 20K ohms and 40K ohms so that
input voltage to ADC is 1.1V which is less than 2.048V of ADC maximum input voltage. The express
equation can represent as follows.

W83L785R

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VCC

where VCC is set to 3.3V.

6.4 Temperature Measurement Machine

The temperature data format is 8-bit two-complement for thermal sensor. The 8-bit temperature data
can be obtained by reading the CR[26h] or CR[27h]. The format of the temperature data is show in
Table 1.

Temperature

8-Bit Digital Output

8-Bit Binary

8-Bit Hex

+125

0111,1101

7Dh

+25

0001,1001

19h

0000,0010

02h

0000,0001

01h

0000,0000

00h

-1

1111,1111

FFh

-2

1111,1110

FEh

-25

1110,0111

E7h

-55

1100,1001

C9h

Table 1.

6.4.1 Monitor temperature from thermistor:

The W83L785R can connect two thermistors to measure three different environment temperature or
remote temperature. The specification of thermistor should be considered to (1)

value is 3435K, (2)

resistor value is 10K ohms at 25

C. In the Figure 3, the themistor is connected by a serial resistor with

10K Ohms, then connect to VREF (pin 17).

6.4.2 Monitor temperature from Pentium II

thermal diode or bipolar transistor 2N3904

The W83L785R can alternate the thermistor to Pentium II

(Deschutes) thermal diode interface or

transistor 2N3904 and the circuit connection is shown as Figure 4. The pin of Pentium II

D- is

connected to power supply ground (GND) and the pin D+ is connected to pin PIIx in the W83L785R.
The resistor R=15K ohms should be connected to VREF to supply the diode bias current and the

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bypass capacitor C=3300pF should be added to filter the high frequency noise. The transistor 2N3904
should be connected to a form with a diode, that is, the Base (B) and Collector (C) in the 2N3904
should be tied together to act as a thermal diode.

2N3904

R=15K, 1%

C=3300pF

Bipolar Transistor

Temperature Sensor

Pentium II

CPU

D+

D-

Therminal

Diode

C=3300pF

R=30K, 1%

VREF

PIITDx

W83L785R

Figure 4.

6.4.3 Over Temperature signal (OVT#)

W83L785R provides two external thermal sensors to detect temperature. When detected
temperature exceeds the over-temperature value, pin OVT# will be asserted until the
temperature goes below the hysteresis temperature. Pin OVT# has 2 operating modes:

6.4.3.1 Comparator Mode :

At this mode, temperature exceeding T

causes the OVT# output activated until the temperature

is less than T

HYST

. ( Figure 5)

6.4.3.2 Interrupt Mode:

At this mode, temperature exceeding T

causes the OVT# output activated indefinitely until reset

by reading interrupt status register. Temperature exceeding T

, then OVT# asserted, and then

temperature going below T

HYST

will also cause the OVT# activated indefinitely until reset by

reading temperature sensor1 or sensor2 registers. Once the OVT# is activated by exceeding T

then reset, if the temperature remains above T

HYST

, the OVT# will not be activated

again.( Figure 5)

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HYST

*Interrupt Reset when Interrupt Status Register is read

OVT#

(Comparator Mode; default)

(Interrupt Mode)

Figure 5.

6.4.4 Temperature Fault (Temp_fault #)

W83L785R provides a good protection for temperature. Set pin11(TEMP_FAULT#) to
monitor temperature and enable TEMP_FAULT# function. When VTIN1(Pin19) or VTIN(Pin18)
temperature exceeds Temperature fault limit in CR53,or R54 pin11 TEMP_FAULT# will be
asserted(Figure 6).

Figure 6. TEMP_FAULT

TEMP_FAULT limit

TEMP_FAULT#

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6.5 FAN Speed Count and FAN Speed Control

6.5.1 Fan speed count

Inputs are provided by the signals from fans equipped with tachometer outputs. The level of these
signals should be set to TTL level, and maximum input voltage cannot be over VCC. If the input
signals from the tachometer outputs are over the VCC, the external trimming circuit should be added
to reduce the voltage to obtain the input specification. The normal circuit and trimming circuits are
shown as Figure 7.

Determine the fan counter according to:

Count

RPM Divisor

1 35 10

In other words, the fan speed counter has been read from register CR28 or CR29, the fan speed can
be evaluated by the following equation.

RPM

Count

Divisor

1 35

The default divisor is 2 and defined at CR47.bit0~2, bit4~6 which are three bits for divisor. That
provides very low speed fan counter such as power supply fan. The followed table is an example for
the relation of divisor, RPM, and count.

Divisor

Nominal

RPM

Time per

Revolution

Counts

70% RPM

Time for 70%

8800

6.82 ms

153

6160

9.74 ms

2 (default)

4400

13.64 ms

153

3080

19.48 ms

2200

27.27 ms

153

1540

38.96 ms

1100

54.54 ms

153

770

77.92 ms

550

109.08 ms

153

385

155.84 ms

275

218.16 ms

153

192

311.68 ms

137

436.32 ms

153

623.36 ms

128

872.64 ms

153

1246.72 ms

Table 2.

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FAN Out

+12V

GND

Pull-up resister

4.7K Ohms

+12V

Fan Input

Pin 1
Pin 2

W83L785R

22K~30K

10K

FAN

Connector

FAN Out

+12V

GND

Pull-up resister < 1K
or totem-pole output

+12V

Fan Input

Pin 1
Pin 2

W83L785R

> 1K

Figure 7-2. Fan with Tach Pull-Up to +12V, or
Totem-Pole Putput and Zener Clamp

3.3V Zener

Figure 7-1. Fan with Tach Pull-Up to +12V, or Totern-Pole
Output and Register Attenuator

FAN Out

+5V

GND

Pull-up resister

4.7K Ohms

+5V

Fan Input

Pin 1
Pin 2

W83L785R

1K~2.7K

10K

FAN

Connector

FAN Out

+5V

GND

Pull-up resister < 1K
or totem-pole output

+5V

Fan Input

Pin 1
Pin 2

W83L785R

> 1K

Figure 7-4. Fan with Tach Pull-Up to +5V, or
Totem-Pole Putput and Zener Clamp

3.3V Zener

Figure 7-3. Fan with Tach Pull-Up to +5V, or Totern-Pole
Output and Register Attenuator

6.5.2 Fan speed control

The W83L785R provides four sets for fan PWM speed control. The duty cycle of PWM can be
programmed by a 8-bit register which are defined in the CR81h and CR83h. The default duty cycle is
set to 100%, that is, the default 8-bit registers is set to FFh. The expression of duty can be
represented as follows.

Duty

cycle

Programmed 8 - bit Register Value

255

(%)

100%

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+12V

FAN

NMOS

PNP Transistor

PWM Clock Input

+5V

FAN

NMOS

PNP Transistor

PWM Clock Input

Figure 8.

6.6 SMI#

6.6.1 Temperature

Pin SMI# for temperature has 3 modes.

6.6.1.1 Comparator Interrupt Mode

Temperature exceeding T

causes an interrupt and this interrupt will be reset when reading all of

the Interrupt Status Registers. Once an interrupt event has occurred by exceeding T

, then reset,

if the temperature remains above the T

HYST

, the interrupt will occur again when the next

conversion has completed. If an interrupt event has occurred by exceeding T

and not reset, the

interrupts will not occur again. The interrupts will continue to occur in this manner until the
temperature goes below T

HYST

. (Figure 9-1)

6.6.1.2 Two-Times Interrupt Mode

Temperature exceeding T

causes an interrupt and then temperature going below T

HYST

will also

cause an interrupt if the previous interrupt has been reset by reading all the interrupt Status
Register. Once an interrupt event has occurred by exceeding T

, then reset, if the temperature

remains above the T

HYST

, the interrupt will not occur. (Figure 9-2 )

6.6.1.3 One-Time Interrupt Mode

Temperature exceeding T

causes an interrupt and then temperature going below T

HYST

will not

cause an interrupt. Once an interrupt event has occurred by exceeding T

, then going below

HYST,

an interrupt will not occur again until the temperature exceeding T

. (Figure 9-3)

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HYST

Figure 9-1. Comparator Interrupt Mode

*Interrupt Reset when Interrupt Status Registers are read

HYST

Figure 9-2. Two-Times Interrupt Mode

SMI#

*Interrupt Reset when Interrupt Status Registers are read

HYST

Figure 9-3. One-Time Interrupt Mode

SMI#

6.6.2 Voltage

SMI# interrupt for voltage is Two-Times Interrupt Mode. Voltage exceeding high limit or going
below low limit will causes an interrupt if the previous interrupt has been reset by reading all the
interrupt Status Register. (Figure 10-1)

6.6.3 Fan

SMI# interrupt for fan is Two-Times Interrupt Mode. Fan count exceeding the limit, or exceeding
and then going below the limit (set at value ram index 3Bh and 3Ch), will causes an interrupt if
the previous interrupt has been reset by reading all the interrupt Status Register. (Figure 10-2)

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7. SPECIFICATIONS

7.1 Absolute Maximum Ratings

PARAMETER

RATING

UNIT

Power Supply Voltage

-0.5 to 7.0

Input Voltage

-0.5 to V

+0.5

Operating Temperature

0 to +70

Storage Temperature

-55 to +150

Note: Exposure to conditions beyond those listed under Absolute Maximum Ratings may adversely affect the life and reliability of the
device.

7.2 DC Characteristics

(Ta = 0

C to 70

C, V

= 5V

10%, V

= 0V)

PARAMETER

SYM. MIN. TYP. MAX. UNIT

CONDITIONS

I/O

12t

- TTL level bi-directional pin with source-sink capability of 12 mA

Input Low Voltage

0.8

Input High Voltage

2.0

Output Low Voltage

0.4

= 12 mA

Output High Voltage

2.4

= - 12 mA

Input High Leakage

LIH

+10

= V

Input Low Leakage

LIL

-10

= 0V

I/O

12ts

- TTL level bi-directional pin with source-sink capability of 12 mA and schmitt-trigger level

input

Input Low Threshold Voltage

0.5

0.8

1.1

= 5 V

Input High Threshold Voltage

1.6

2.0

2.4

= 5 V

Hysteresis

0.5

1.2

= 5 V

Output Low Voltage

0.4

= 12 mA

Output High Voltage

2.4

= - 12 mA

Input High Leakage

LIH

+10

= V

Input Low Leakage

LIL

-10

= 0V

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11.2 DC Characteristics, continued

PARAMETER

SYM.

MIN.

TYP.

MAX.

UNIT

CONDITIONS

OUT

12t

- TTL level output pin with source-sink capability of 12 mA

Output Low Voltage

0.4

= 12 mA

Output High Voltage

2.4

= -12 mA

- Open-drain output pin with sink capability of 8 mA

Output Low Voltage

0.4

= 8 mA

- Open-drain output pin with sink capability of 12 mA

Output Low Voltage

0.4

= 12 mA

- Open-drain output pin with sink capability of 48 mA

Output Low Voltage

0.4

= 48 mA

- TTL level input pin

Input Low Voltage

0.8

Input High Voltage

2.0

Input High Leakage

LIH

+10

= V

Input Low Leakage

LIL

-10

= 0 V

- TTL level Schmitt-triggered input pin

Input Low Threshold Voltage

0.5

0.8

1.1

= 5 V

Input High Threshold Voltage

1.6

2.0

2.4

= 5 V

Hysteresis

0.5

1.2

= 5 V

Input High Leakage

LIH

+10

= V

Input Low Leakage

LIL

-10

= 0 V

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7.3 AC Characteristics

VALID DATA

SCL

SDA IN

SDA OUT

t HD;SDA

SCL

HD;DAT

SU;STO

SU;DAT

Serial Bus Timing Diagram

Serial Bus Timing

PARAMETER

SYMBOL

MIN.

MAX.

UNIT

SCL clock period

SCL

Start condition hold time

HD;SDA

4.7

Stop condition setup-up time

SU;STO

4.7

DATA to SCL setup time

SU;DAT

120

DATA to SCL hold time

HD;DAT

SCL and SDA rise time

1.0

SCL and SDA fall time

300

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8. HOW TO READ THE TOP MARKING

The top marking of W83L785R

W83L785R

046OA

2826978Y

Left: Winbond logo

1st line: Type number W83L785R, R means SSOP (Thickness = 209mil).
2nd line: Tracking code 2 826978Y

2: wafers manufactured in Winbond FAB 2

826978Y: wafer production series lot number

3rd line: Tracking code 046 A A

046: packages made in 2000, week 46
O: assembly house ID; A means ASE, O means OSE, G means Greatek
A: IC revision; A means version A, B means version B

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9. PACKAGE DRAWING AND DIMENSIONS

20 SSOP-209 mil

A2 A

SEATING PLANE

DTEAIL A

DETAIL A

SEATING PLANE

0.002

0.197
0.291

7.80

7.40

8.20

5.30

10.05
5.00

A1
A2

5.60

10.35

10.20

2.00

1.85

0.323

0.307

0.073

0.079

0.220

0.395

0.407

0.401
0.209

MIN.

DIMENSION IN INCH

SYMBOL

DIMENSION IN MM

MIN.

NOM

MAX.

NOM

0.05

e
L

0.009

0.015

0.004

0.008

0.021

0.030

0.050

0.004

0.22

0.38

0.09

0.21

0.65

0.0256

0.55

0.75

1.25

0.10

0.95

0.037

1.75

1.65

0.065

0.069

Headquarters

No. 4, Creation Rd. III

Science-Based Industrial Park

Hsinchu, Taiwan

TEL: 886-35-770066

FAX: 886-35-789467

www: http://www.winbond.com.tw/

Taipei Office

11F, No. 115, Sec. 3, Min-Sheng East Rd.

Taipei, Taiwan

TEL: 886-2-7190505

FAX: 886-2-7197502

TLX: 16485 WINTPE

Winbond Electronics (H.K.) Ltd.

Rm. 803, World Trade Square, Tower II

123 Hoi Bun Rd., Kwun Tong

Kowloon, Hong Kong

TEL: 852-27516023-7

FAX: 852-27552064

Winbond Electronics
(North America) Corp.

2730 Orchard Parkway

San Jose, CA 95134 U.S.A.

TEL: 1-408-9436666

FAX: 1-408-9436668

Please note that all data and specifications are subject to change without
notice. All the trade marks of products and companies mentioned in this data
sheet belong to their respective owners.

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. Winbond customers using or selling these
products for use in such applications do so at their own risk and agree to fully
indemnify Winbond for any damages resulting from such improper use or sale.

10.

W83L785R SCHEMATICS

785.SCH

0.1

W83L785R Application Circuit

Custom

Friday, March 30, 2001

Title

Size

Document Number

Rev

Date:

Sheet

CPU_VCORE

1.5V

VCC

2.5V

VCC

+12V

VCC

Fan5VCC

VCC

Fan5VCC

VREF

SDA

GP5

GP6

OVT#

SCL

GP13

SMI#

VTIN2

SDA

PWMOUT2

FANIN2

FANIN1

PWMOUT1

GP13

VTIN1

VREF

VTIN1
VTIN2

SCL

PWMOUT1

FANIN1

PWMOUT2

FANIN1

PWMOUT1

FANIN2

R16

10K

R18

100k

R17

10K

R34

10K 1%

R29

30K 1%

RT1

THERMISTOR

10K 1%

CAP

3300p

R38
4.7k

R39

4.7k

R40

WINBOND ELECTRONICS CORP.

R19

200k

R44
1K

R45
1K

R46
1K

R1
4.7K

R11
10K

R14

4.7K

0.1u

W83785R

1
2
3
4
5
6
7
8
9

20
19
18
17
16
15
14
13
12
11

FANIN1/GPIO1
FANIN2/GPIO2
PWMOUT1
PWMOUT2
GPIO5
GPIO6
SMI#/GPIO7
OVT#/GPIO8
SCL
SDA

VCC

VTIN1
VTIN2

VREF

VCORE/GPIO16

+1.5V/GPIO15
+2.5V/GPIO14

GPIO13

GND

TEMP_FAULT#/GPO11

10u/16V

4.7K

R13
4.7K

R41

R28
10K

R24

4.7K

JP1

HEADER 3

Q1
3906

R22

1N4148

47u

R37
10K

R33

4.7K

JP2

HEADER 3

Q3
3906

R32

R30

4.7K

1N4148

47u

R35

100

R27

27K

R36

27K

R21
4.7K

R31
4.7K

Q4
MOSFET N

MOSFET N

R26

100

R20

4.7K

R24

4.7K

47u

Q1
3906

JP2

HEADER 3

1N4148

R27

Q4
MOSFET N

R37
10K

R30

4.7K

R21
4.7K

R20

4.7K

JP1

HEADER 3

R28
10K

R22

R35

100

R26

100

47u

R33

4.7K

R31
4.7K

MOSFET N

R32

R36

1N4148

Q3
3906

PIID-

PIID+

SMDAT

TEMP_FAULT#

GPIO6

THRM#

GPIO5

EXTSMI#

SMCLK

VOLTAGE SENSORING CIRCUIT

Rev.

0.1:W83L785R application circuit. 3.3VCC

{

From PII/PIII CPU

TEMPERATURE SENSORING CIRCUIT

NOTE:

ALL GPIO PIN Must add pull-up resistor

To chipset

}

(max 2.048V)

PWM1 Circuit for FAN1 speed Control

PWM2 Circuit for FAN2 speed Control

Signal
Power

GND

Signal
Power

GND

PWMOUT1 is
open-drain default.

PWMOUT2 is
open-drain default.

W83784R has SMARTFAN function

open-drain default.

PWMOUT1 is

Signal

PWMOUT2 is

GND

PWM2 Circuit for FAN2 speed Control

W83784R has SMARTFAN function

open-drain default.

Power

PWM1 Circuit for FAN1 speed Control

FOR 5V FAN

FOR 12V FAN

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: W83L785R

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: W83L785R