Logic Design for ArrayBased Circuitsby Donnamaie E. WhiteCopyright © 1996, 2001, 2002 Donnamaie E. White 


External SetUp and Hold TimesLast Edit July 22, 2001 Case 1: When The Timing Specifications Are NominalFor the case where the vendor has specified timing delays as nominal, with adjustment factors or worstcase multipliers, the following procedures can be applied. The worstcase multiplier (WCM) may be the product of adjustment factors for temperature, voltage and process. SetUp Time  Generic EquationWhen computing the setup time, it is desirable to assume that the data propagation path delay is the worstcase maximum and that the clock path propagation delay is a worstcase minimum for the operating conditions. The generic equation is:
Hold Time  Generic EquationWhen computing the hold time, it is desirable to assume that the data propagation path delay is the worstcase minimum and that the clock path propagation delay is a worstcase maximum for the operating conditions. The generic equation is:
Terminology Definitions
Variations in SpecificationsEven when the propagation delays through a macro are specified as typical or nominal, the setup and hold times for flip/flops and latches may be specified as worstcase maximum. In that case, the macro setup (T_{sumacro}) and hold (T_{hmacro}) times will not be multiplied by a worstcase multiplier or adjustment factor . 

Copyright @ 2001,
2002 Donnamaie E. White, White
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