Intel 440GX Layout Checklist, Applications and Add-in Hardware, Routing and Board Fabrication

Models: 440GX

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3.23Layout Checklist

Design Checklist

3.23Layout Checklist

3.23.1Routing and Board Fabrication

VRM 8.2 Support: Is the VccCORE trace/power plane sufficient to ensure VccCORE meets specification. See the Intel® Pentium® II Datasheet for trace/power plane resistance and length requirements.

VTT should be routed with at least a 50 mil (1.25mm) wide trace.

VREF traces should be isolated to minimize the chance of cross-talk.

VccCORE from the voltage regulator to Slot 1 should be an “island” as opposed to a trace.

Decoupling capacitor traces should be as short and wide as possible.

GTL+ signals should follow the layout guidelines, see AP-524 Intel® Pentium® Pro Processor GTL+ Layout Guidelines for further information. If the recommendations are not followed, simulations should be been run using the actual layout.

GTL+ lines should be spaced as far apart as possible (at least 10 mils). Running GTL+ signals closer together (5 mils) for less than 1” (2.5cm) is acceptable.

There should be no CMOS/TTL signals running parallel to GTL+ signals. If they must run in parallel, separate them on different layers with a well decoupled power or ground plane. If they must run parallel on the same layer, then separate the traces by a minimum of 25 mils.

Proper operation of the IDE circuit depends on the total length of the IDE bus. The total signal length from the IDE drivers (PIIX4E pins) to the end of the IDE cables should not exceed 18”. Therefore, the PIIX4E should be located at close as possible to the IDE headers to allow the IDE cable to be as long as possible.

3.23.2Design Consideration

The BCLK trace to the ITP562 connector is not required to have a matched trace length to the other BCLK signals to the Slot 1 connector or AGPset.

3.24Applications and Add-in Hardware

3.24.1Design Consideration

See the MMX™ Technology Developer’s Guide for information on the definition and use of Intel’s MMX™ technology instruction set extension. This guide provides optimization guidelines for developers of software utilizing the performance enhancement the instruction set offers.

Contact your local Intel field sales representative for information on IHVs and ISVs utilizing Intel’s MMX™ technology.

Contact your local Intel Field Sales representative for information on utilizing Intel’s latest AGP technology.

Intel®440GX AGPset Design Guide

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Intel 440GX manual Layout Checklist, Applications and Add-in Hardware, Routing and Board Fabrication, Design Consideration