CS150 Week 6, lecture 1 Covers:1) Monster input gates2) PLAs, PALs, ROMs1) Monster input gates How many 2-input AND gates do you need to make a 64 input AND gate? And what’s the minimum number ofstages necessary? To give you the idea, let’s do a simpler one: An 8-input AND gate. Total: 7 Gates Total: 3 Gates Total: 1 GatePhillips’ AND gates have a 200ps/gate delay. So 3 stages would have a 600ps+ delay from the time the input changes to when the output changes.Gates: ?Stages: ?2) PLAs, PALs, ROMsProgrammable logic devices: PLAs: AND and OR plane adjustable. PALs: Only AND plane adjustable.Programmable memory devices: ROM: Regurgitates whatever was burned into it…Picture of a PLA: ( are fused conections. ) __ __ A A B B _OUTPUT = AB +
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