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John McMaster edited this page Feb 28, 2018 · 21 revisions

Notes on creating a device timing model

Fanout effect timing info. IIRC I saw about 20% variation across things

Node

SPEED_CLASS shifts around a lot depending on other parameter values, which also shift around

A few interesting comparisons

  • SPEED_CLASS difference
    • BASE_CLOCK_REGION:X0Y3 CLASS:node COST_CODE:21 COST_CODE_NAME:HQUAD IS_BAD:0 IS_COMPLETE:1 IS_GND:0 IS_INPUT_PIN:0 IS_OUTPUT_PIN:0 IS_PIN:0 IS_VCC:0 NAME:INT_L_X0Y199/WW4BEG3 NUM_WIRES:13 PIN_WIRE:65535 SPEED_CLASS:100
    • BASE_CLOCK_REGION:X0Y3 CLASS:node COST_CODE:21 COST_CODE_NAME:HQUAD IS_BAD:0 IS_COMPLETE:1 IS_GND:0 IS_INPUT_PIN:0 IS_OUTPUT_PIN:0 IS_PIN:0 IS_VCC:0 NAME:INT_L_X2Y199/WW4BEG3 NUM_WIRES:13 PIN_WIRE:65535 SPEED_CLASS:284
    • Everything is basically the same, but speed class is still different
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