Trace Length Equalization Procedures With Allegro - Intel 855GME Design Manual

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Intel 855GME Chipset and Intel
®
Intel Pentium
Figure 14. Reference Trace Length Selection
5. Use the Allegro* I (info) command to report the current length of the trace to be equalized.
Record the length in cell B2 of the Excel* spreadsheet.
6. Use the Allegro* "Cut" command to cut the trace in two locations of the serpentine as shown
in Figure
7. Use the Allegro* "Move ix" (i.e., if vertical routing) command to move the floating section by
the Δ/2 distance listed in cell B4.
8. Reconnect the floating segment if needed.
9. Repeat steps 5 through 8 for the reminder of the traces in the group.
Figure 15. Trace Length Equalization Procedures with Allegro*
RE FERE NCE L ENG TH
S TARTING LEN G TH
Δ
Δ / 2
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M/Celeron M Processor FSB Design and Power Delivery Guidelines
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15. This operation generates a floating section of the serpentine.
5950
6012
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Δ = Starting Length – Reference Length
January 2007
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6300ESB ICH Embedded Platform Design Guide
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Reference Length 5950 mil
CU T
M ove ix - Δ /2
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