W83783S_07 WINBOND [Winbond], W83783S_07 Datasheet - Page 17

• Manufacturer Part Number: W83783S_07
• Description: Winbond H/W Monitoring IC
• Manufacturer: WINBOND [Winbond]

6.3.3 Monitor temperature from thermistor:
W83783S can connect three thermistors to measure three different environmental temperatures. The
specification of thermistor should be considered to (1) β value is 3435K, (2) resistor value is 10K ohms
at 25°C. In the Figure 11, the themistor is connected by a serial resistor with 10K Ohms, and then
connect to VREF (Pin 37).
6.3.4 Monitor temperature from Pentium II
W83783S can alternate the thermistor to Pentium II
transistor 2N3904 and the circuit connection is shown as Figure 12. The pin of Pentium II
connected to power supply ground (GND) and the pin D+ is connected to pin PIIx in W83783S. The
resistor R=30K ohms should be connected to VREF to supply the diode bias current and the 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 togeter to act as a thermal diode.
Temperature Sensor
Bipolar Transistor
Pentium II
Therminal
CPU
B
Diode
OR
C
E
2N3904
D+
D-
Figure 12.
R=30K, 1%
TM
- 13 -
thermal diode or bipolar transistor 2N3904
R=30K, 1%
C=3300pF
TM
C=3300pF
(Deschutes) thermal diode interface or
Publication Release Date: August 21, 2007
VREF
PIITDx
PIITDx
W83783S
W83783S
Revision 1.0
TM
D- is