Logic Design for Array-Based Circuits

by Donnamaie E. White

Copyright © 1996, 2001, 2002 Donnamaie E. White


Power Considerations

Last Edit July 22, 2001

Total Power Dissipation

Add the DC power computation result to the AC power computation result.

Pd = PdDC + PdAC

The result is the worst-case power dissipation to be used in computing junction temperature.

Depending on the array series, one of the terms may be zero or close enough to zero to discount.


  1. Is AC power a factor in the array series of interest? (Use the same series used in the DC power exercises.)

  2. What equation is used by the array vendor you have chosen?

  3. AMCC Q20000 Series: Continue the problem started in the DC power exercises and add AC power to the DC power already computed for the circuit. The number of input macros is 84. The number of internal macros is 112. There are no Darlington output macros. Assume all macros switch at 500MHz (Note: Is there a pulse width violation for any macros at this speed?)

  4. Compare both versions of the above problem as described earlier. Which one is best?

Copyright @ 2001, 2002 Donnamaie E. White, White Enterprises
For problems or questions on these pages, contact dew@Donnamaie.com