W83627DHG-PT Nuvoton Technology Corporation of America, W83627DHG-PT Datasheet - Page 50

• Manufacturer Part Number: W83627DHG-PT
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83627DHG-PT

• Pin Count: 128
• Lead Free Status / RoHS Status: Compliant

8.5
PECI (Platform Environment Control Interface) is a new digital interface to read the CPU temperature
of Intel® CPUs. With a bandwidth ranging from 2 Kbps to 2 Mbps, PECI uses a single wire for self-
clocking and data transfer. By interfacing to the Digital Thermal Sensor (DTS) in the Intel
reports a negative temperature (in counts) relative to the processor’s temperature at which the thermal
control circuit (TCC) is activated. At the TCC Activation temperature, the Intel CPU will operate at
reduced performance to prevent the device from thermal damage.
PECI is one of the temperature sensing methods that the W83627DHG-P supports. The
W83627DHG-P contains a PECI master and reads the CPU PECI temperature. The CPU is a PECI
client.
The PECI temperature values returning from the CPU are in “counts” which are approximately linear in
relation to changes in temperature in degrees centigrade. However, this linearity is approximate and
cannot be guaranteed over the entire range of PECI temperatures. For further information, refer to the
PECI specification. All references to “temperature” in this section are in “counts” instead of “°C”.
Figure 8-8
2) 3VCC (pin 12) = Decimal[2-byte data by GetVolt3p3V()] / 1024 volts
3) “+12V” = Decimal[2-byte data by GetVolt12V()] / 1024 / ((R1+R2) / R2) volts
4) “+5VCC” = Decimal[2-byte data by GetVolt5V()] / 1024 / ((R3+R4) / R4) volts
VIN1 (pin 98) is connected as shown below:
5) “+2.5V” = Decimal[2-byte data by GetVolt2p5V()] / 1024 / ((R5+R6) / R6) volts
VIN0 (pin 99) is connected as shown below:.
VIN2 (pin 97) is connected as shown below:
PECI
+12V
5VCC
2.5V
shows a typical fan speed (PWM duty cycle) and PECI temperature relationship.
R3
30K 1%
R5
10K 1%
R1
150K 1%
R4
10K 1%
R6
10K 1%
W83627DHG-P/W83627DHG-PT
R2
10K 1%
VIN1
VIN2
-40-
VIN0
Publication Release Date: July 09, 2009
®
Version 1.94
CPU, PECI