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


Power ConsiderationsLast Edit July 22, 2001 CMOS and BiCMOS ArraysBiCMOS arrays will simplify the computation since they will only compute DC power for the bipolar interface macros. Note that BiCMOS arrays still have an overhead current CMOS arrays emphasize AC power components and do not usually have DC components listed When Power is Specified Rather then CurrentAnother variation in the computational method occurs when the macros are individually specified with a power dissipation, i.e., use this macro  dissipate this much power. The worstcase multiplier and the worstcase voltage may or may not be accounted for in the computation. Only addition is required to compute the macro power dissipation An overhead component for the bias circuitry may need to be computed and added to the macro sum. If typical power is specified, a worstcase multiplier or adjustment factor may be provided as previously discussed Design Rules when Power is to be Estimated
AC Macro Power DissipationTo compute the AC power for any array, perform the computation shown earlier and repeated here: PAC = 0.20 * ( a * f * G ) where
There will be some variation in the form of the equation depending on the use of gates or macros or outputs as the sizing measure. There will be variation depending on the use of a register ratio and there will be variation in the types of macros for which AC power will be computed.

Copyright @ 2001,
2002 Donnamaie E. White, White
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