Intel Pentium 4 User Manual

Layout Review Checklist
R
Intel
®
Pentium
®
4 Processor / Intel
®
850 Chipset Family Platform Design Guide 289
√ Recommendations Reason/Impact
• Traces should be routed away from board
edges by a distance greater than the trace
height above the ground plane.
• This allows the field around the trace to
couple more easily to the ground plane
rather than to adjacent wires or boards.
• Do not route traces and vias under crystals
or oscillators.
• This will prevent coupling to or from the
clock.
• Trace width to height ratio above the ground
plane should be between 1:1 and 3:1.
• To control trace EMI radiation.
• Traces between decoupling and I/O filter
capacitors should be as short and wide as
practical.
• Long and thin lines are more inductive and
would reduce the intended effect of
decoupling capacitors.
• Vias to decoupling capacitors should be
sufficiently large in diameter.
• To decrease series inductance.
• Avoid routing high-speed LAN* or Phoneline
traces near other high-frequency signals
associated with a video controller, cache
controller, processor, or other similar
devices.
• To minimize crosstalk.
• Isolate I/O signals from high-speed signals. • To minimize crosstalk.
• Place the 82562ET/EM part more than
1.5 inches away from any board edge.
• This minimizes the potential for EMI
radiation problems.
• Verify proper EEPROM size:
 82562ET – 64 word
 82562EM – 256 word
• The 82562EM requires a larger EEPROM to
store the alert envelope and other
configuration information.
• Place at least one bulk capacitor (4.7 µF or
greater OK) on each side of the
82562ET/EM.
• Research and development has shown that
this is a robust design recommendation.
• Place decoupling capacitors (0.1 µF) as
close to the 82562ET/EM as possible.
• RBIAS10 and RBIAS100 resistors should
be 1% values
• These are biasing resistors that require 1%
accuracy. Note that the values shown on the
reference schematic are recommended
starting values. Fine tuning (via IEEE
conformance testing) is required for every
new design.
16.13 Miscellaneous
√ Recommendations Reason/Impact
• 1.8 V Stand By: one 0.1 µF capacitor • Refer to Section 9.12.
• 5 V Reference: two 0.1 µF capacitors • Refer to Section 9.12.
• 5 V Reference Stand By: one 0.1 µF
capacitor
• Refer to Section 9.12.

Intel Pentium 4 Specifications

General

Brand	Intel
Model	Pentium 4
Category	Computer Hardware
Language	English