Mobile Intel Pentium 4 Processor - M and Intel 845MP/MZ Chipset Platform Design Guide

Mobile Intel
®
Pentium
®
4 Processor-M and Intel
®
845MP/845MZ Chipset Platform
102 Design Guide
R
9.1.1. Primary IDE Connector Requirements
Figure 47. Connection Requirements for Primary IDE Connector
4.7K
ohm
Reset#
Primary IDE Connector
ICH3-M
PDD[15:0]
PCIRST#
PDA[2:0]
PDCS1#
PDCS3#
PDIOR#
PDIOW#
PDDACK#
IRQ14
PDDREQ
PIORDY
*Due to ringing, PCIRST# must
be buffered.
3.3V
8.2K-10K
ohm
22 - 47 ohm
PCIRST_BUF#
*
CSEL
Pin32,34N.C.
GPIOx
PDIAG#/
CBLID#
10K ohm
3.3V3.3V
• 22-Ω to 47-Ω series resistors are required on RESET#. The correct value should be determined for
each unique motherboard design, based on signal quality.
• An 8.2-kΩ to 10-kΩ pull-up resistor is required on IRQ14 and IRQ15 to Vcc3_3.
• A 4.7-kΩ pull-up resistor to Vcc3_3 is required on PIORDY and SIORDY.
• Series resistors can be placed on the control and data line to improve signal quality. The resistors
are placed as close to the connector as possible. Values are determined for each unique motherboard
design.
• A 10-kΩ pull-down resistor to ground is required on the PDIAG#/CBLID# signal. This is to prevent
the GPI pin from floating if a device is not present on the Primary IDE interface.