8170 N/B MAINTENANCE

5.1 Pentium 4(Willamette/Northwood) mFC-PGA2 478 pin

Name

Type

Description

VCCIOPLL

Input

VCCIOPLL provides isolated power for internal processor system

 

 

bus PLLs. Follow he guidelines for VCCA, and refer to the Intel®

 

 

Pentium® 4 Processor in the 478-pin Package and Intel® 850

 

 

Chipset Platform Design Guide for complete implementation

 

 

details.

VCCSENSE

Output

VCCSENSE is an isolated low impedance connection to processor

 

 

core power(VCC). It can be used to sense or measure power near

 

 

the silicon with little noise.

VCCVID

Input

There is no imput voltage requirement for VCCVID for designs

 

 

intended tosupport only the Pentium 4 processor in the 478-pin

 

 

package. Refer to the Intel® Pentium® 4 Processor in the

 

 

478-pin Package and Intel® 850 Chipset Platform Design

 

 

Guide for more information.

VID[4:0]

Output

VID[4:0] (Voltage ID) pins can be used to support automatic

 

 

selection of power supply voltages (Vcc). These pins are not

 

 

signals, but are either an open circuit or a short circuit to VSS

 

 

on the processor. The combination of opens and shorts

 

 

defines the voltage required by the processor. The VID pins are

 

 

needed to cleanly support processor voltage specification

 

 

variations. See 1.4 for definitions of these pins. The power

 

 

supply must supply the voltage that is requested by these pins,

 

 

or disable itself.

VSSA

Input

VSSA is the isolated ground for internal PLLs.

 

 

 

VSSSENSE

Output

VSSSENSE is an isolated low impedance connection to processor

 

 

core VSS. It can be used to sense or measure ground near the

 

 

silicon with little noise

TMS

Input

TMS (Test Mode Select) is a JTAG specification support signal

 

 

used by debug tools.

TRDY#

Input

TRDY# (Target Ready) is asserted by the target to indicate that

 

 

it is ready to receive a write or implicit writeback data transfer.

 

 

TRDY# must connect the appropriate pins of all system bus

 

 

agents.

TRST#

Input

TRST# (Test Reset) resets the Test Access Port (TAP) logic.

 

 

TRST# must be driven low during power on Reset. This can be

 

 

done with a 680 . pull-down resistor.

VCCA

Input

VCCA provides isolated power for the internal processor core

 

 

PLLs. Refer to the Intel® Pentium® 4 Processor in the 478-pin

 

 

Package and Intel® 850 Chipset Platform Design Guide for

 

 

complete implementation details.

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