Intel Pentium 4 User Manual

Layout Review Checklist
R
Intel
®
Pentium
®
4 Processor / Intel
®
850 Chipset Family Platform Design Guide 273
16.1.6 AGTL+ ( V
REF
HDVREF [3:0], HAVREF [1:0] and CCVREF)
√ Recommendations Reason/Impact/Documentation
• Processor must have at least one dedicated
voltage divider. There are four GTLREF
signals on the processor. Keep voltage
divider within 1.5 inches of the first V
REF
pin.
• Refer to Section 5.3.
• 82850 MCH requires one dedicated voltage
divider. Voltage divider must be within 1.5
inches of MCH V
REF
ball.
• Refer to Section 5.5.
• Decouple each voltage divider with a 1 µF
capacitor and each V
REF
pin with a 220 pF
capacitor as close to the pin as possible.
• This recommendation provides a low
impedance line without the cost of additional
plane or island.
• Refer to Section 5.3.
• When routing V
REF
use a ~12 mil line trace
width.
• This recommendation provides a low
impedance line without the cost of additional
plane or island.
• Refer to Section 5.2.
• Keep other signals 10 mils away from V
REF
signal.
• V
REF
signal must be a clean as possible
from noise.
• Refer to Section 5.3.

Intel Pentium 4 Specifications

General

Brand	Intel
Model	Pentium 4
Category	Computer Hardware
Language	English