W83L785R Datasheet, PDF (12/38 Pages) Winbond – WINBOND H/W MONITORING IC FOR NOTEBOOK

W83L785R/W83L785G
6.4.1 Voltage Monitor input can not be over 2.048V:
The input voltage VIN1 or Vcore can be expressed as following equation:
VIN1 = V_+2.5V
×
R₂
R₁ + R₂
. V_+2.5V is +2.5V inputs.
The value of R1 and R2 can be selected to 100K Ohms and 100K 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
/G and the second function is that this voltage with 3.3V is connected to internal serial resistors to
monitor the +3.3V voltage. The values 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.
V_in
= VCC ×
20KΩ
20KΩ + 40KΩ
≅ 1.1V
where VCC is set to 3.3V.
6.5 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.
Table 1
TEMPERATURE
8-BIT DIGITAL OUTPUT
8-BIT BINARY
8-BIT HEX
+125°C
0111,1101
7Dh
+25°C
0001,1001
19h
+2°C
0000,0010
02h
+1°C
0000,0001
01h
+0°C
0000,0000
00h
-1°C
1111,1111
FFh
-2°C
1111,1110
FEh
-25°C
1110,0111
E7h
-55°C
1100,1001
C9h
-8-