Platform Power Delivery Guidelines
186
Design Guide
NOTE:
The outlined area in the figure is the 3.3 V plane. Place at least five 0.1
µ
F capacitors in this area.
12.5.3
PCIRST# Implementation
PCI-X requires a 100 ms delay from valid power (PWRGD) to reset deassertion (PCIRST#). The
system design must ensure this requirement is met.
The P64H2 reset must be deasserted within 60 ns of the MCH reset deassertion. Intel strongly
recommends the customer to measure this timing relationship on their board. Failure to meet this
guideline may result in a system failing to boot.
12.5.4
P64H2 Power Sequencing Requirement
3.3 V and 1.8 V must be valid before the first CLK66 pulse is drive to the P64H2. This can be
garunteed by gating the CK408 cocks using a power good signal from the 1.8 V regulator.
Figure 12-23. 3.3V PCI/PCI-X (VCC_3.3) Capacitor Placement
0.1uF
AD24
AD1
A24
A1
Summary of Contents for Xeon
Page 24: ...Introduction 24 Design Guide This page is intentionally left blank ...
Page 30: ...Component Quadrant Layout 30 Design Guide This page is intentionally left blank ...
Page 52: ...Platform Clock Routing Guidelines 52 Design Guide This page is intentionally left blank ...
Page 66: ...System Bus Routing Guidelines 66 Design Guide This page is intentionally left blank ...
Page 118: ...Intel 82870P2 P64H2 118 Design Guide This page is intentionally left blank ...
Page 146: ...I O Controller Hub 146 Design Guide This page is intentionally left blank ...
Page 148: ...Debug Port 148 Design Guide This page is intentionally left blank ...
Page 210: ...Schematic Checklist 210 Design Guide This page is intentionally left blank ...
Page 220: ...Layout Checklist 220 Design Guide This page is intentionally left blank ...
Page 222: ...Schematics 222 Design Guide This page is intentionally left blank ...