23 lines
986 B
Markdown
Executable File
23 lines
986 B
Markdown
Executable File
Problem 4, Part D was omitted from the solutions. It is presented here.
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D\) What is t_pd of the fastest equivalent circuit (i.e. one that
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implements the same function) built using only the three components
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listed above?
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Lets start by reducing the logic equation....I'm going to use three
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intermediary signals, alpha, beta and gamma, and pull identity numbers
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from the slides
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alpha=!(A+B) beta=!(alpha+A) gamma=!(alpha+!B) OUT=!(beta+gama)
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OUT=!(!(alpha+A) + !(alpha+!B)) substitution OUT=!(!(!(A+B)+A) +
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!(!(A+B)+!B)) substitution OUT=!(!(!A\*!B+A) + !(!A\*!B+!B)) demorgans
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OUT=!!(!A\*!B+A) \* !!(!A\*!B+!B) demorgans OUT= (!A\*!B+A) \*
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(!A\*!B+!B) identity 4 elementary OUT= (!A\*!B+A) \* (!B) identity 10
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absorption OUT= (!A\*!B+A\*!B) identity 8 distributivity OUT= !B (!A +
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A) identity 8 distributivity OUT= !B 5 elementary
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Since this can be implemented with a single inverter, the smallest
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propagation delays is 1ns.
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[Category:FPGAWorkshop](Category:FPGAWorkshop "wikilink") |