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Would this work as an XOR logic gate? Answered

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Hi, I'm new to logic gates and I am wondering if this would work as (or is) a XOR logic gate.

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steveastroukBest Answer (author)2011-03-27

L.'s reply to Sean applies to the transistor too..

In the first case, when A=0 B=0 then the output of the OR gate is 0 and the output of the NAND gate is 1, there is 5V on the base and 0 V on the collector. This is an NPN transistor, so there is a forward biased diode between +5 and 0V. Smoke.

Steve

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lemonie (author)2011-03-25


That's a OR and a NAND?
Where are your truth tables? (that's how I figured it out...)

If this is correct, yes it should do an EX-OR. But why not connect the outputs to the same leg of the transistor?

L

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seandogue (author)lemonie2011-03-26

lemonie, for an answer to why-not?, examine the case where a=b=0 or a=b=1. smoke

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lemonie (author)seandogue2011-03-27


The outputs will be 1 or 0, high or low (and equally so). As semiconductors I'd expect a diode-functionality in them, so I don't see a problem myself.

L

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