Design Guide
119
I/O Controller Hub
I/O Controller Hub
9
9.1
IDE Interface
This section contains guidelines for connecting and routing the ICH3-S IDE interface. The ICH3-S
has two independent IDE channels. This section provides guidelines for IDE connector cabling and
motherboard design, including component and resistor placement, and signal termination for both
IDE channels. The ICH3-S has integrated the series resistors that have been typically required on
the IDE data signals (PDD[15:0] and SDD[15:0]) running to the two ATA connectors. While it is
not anticipated that additional series termination resistors will be required, OEMs should verify
motherboard signal integrity through simulation. Additional external 0
Ω
resistors can be
incorporated into the design to address possible noise issues on the motherboard. The additional
resistor layout increases flexibility by offering stuffing options at a later date.
The IDE interface can be routed with 5 mil traces on 7 mil spaces, and must be less than 8 inches
long (from ICH3-S to IDE connector). Additionally, maximum length difference between the
longest and shortest trace lengths of a channel is 0.5 inch.
9.1.1
Cabling
•
Length of cable:
Each IDE cable must be equal to or less than 18 inches.
•
Capacitance:
The capacitance of each IDE cable must be less than 35 pF.
•
Placement:
A maximum of 6 inches is allowed between drive connectors on the cable. If a
single drive is placed on the cable, it should be placed at the end of the cable. If a second drive
is placed on the same cable, it should be placed on the next closest connector to the end of the
cable (no more than 6 inches away from the end of the cable).
•
Grounding:
Provide a direct low impedance chassis path between the motherboard ground
and hard disk drives.
•
ICH3-S Placement:
The ICH3-S must be placed equal to or less than 8 inches from the ATA
connector(s).
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 ...