W83627DHG Nuvoton Technology Corporation of America, W83627DHG Datasheet - Page 48

• Manufacturer Part Number: W83627DHG
• Description: IC I/O CONTROLLER 128-QFP
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83627DHG

• Applications: PC's, PDA's
• Interface: LPC
• Voltage - Supply: 3.3V
• Package / Case: 128-XFQFN
• Mounting Type: Surface Mount
• Pin Count: 128
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.5
PECI (Platform Environment Control Interface) is a proprietary derivation of SST. It is one of the
temperature sensing methods that the W83627DHG supports. With a bandwidth ranging from 2 kbps to
2 Mbps, the PECI uses a single wire – no additional control lines needed – for self-clocking and data
transfer. By interfacing to the Digital Thermal Sensor on the Intel
temperature value relative to the processor’s temperature at which the thermal control circuit (TCC) is
activated.
To enable the PECI functionalities of the W83627DHG, BIOS/Software should follow the steps below:
1. Program Logical Device C, CR[E8h] bit (1..0) for PECI speed selection to meet the bit timing limits of
CPU with PECI function. We recommend this bit is set to “11” for better stability.
2. Program Logical Device C, CR[E5h] bit (7..4) for each PECI Agent to match the number of domains
in the processors. Setting to “1” enables the W83627DHG to issue GetTemp(0) and GetTemp(1)
commands to access the PECI temperatures of domain 0 and domain 1. Setting to “0” enables the
W83627DHG to issue GetTemp(0) command for domain 0.
3. Program Logical Device C, CR[E0] bit (3..0) for each PECI Agent. Setting to “1” returns the PECI
temperature of domain 1 to the temperature reading register. Setting to “0” returns the PECI
temperature of domain 0 to the temperature reading register. If CR[E5] bit 1 is set to “1”, the higher
PECI temperature of domain 0 and domain 1 is returned to the temperature reading register. See the
example below for more details about the temperature reading register(s)
4. Program Logical Device C, CR[E0h] bit (7..4) for each PECI Agent. Setting to “1” enables the
W83627DHG to access the agent. The power-on default is disabled. After an agent is enabled, the
W83627DHG issues PING and GetTemp commands to obtain the PECI temperature
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
VIN2 (pin 97) is connected as shown below:
PECI
+12V
5VCC
2.5V
R3
30K 1%
R5
10K 1%
R1
150K 1%
R4
10K 1%
R6
10K 1%
R2
10K 1%
VIN1
VIN2
-36-
VIN0
Publication Release Date: Aug, 22, 2007
®
CPU, PECI reports a negative
W83627DHG
Version 1.4