Comparator circuit - RF Cafe Forums

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Guest
Post subject: Comparator circuit Posted: Wed Oct 05, 2005 5:23 am
I am new in circuit designing, i have to design a circuit that compares a -ve and a +ve input and gives +ve input at the output only if the -ve input is -5V, otherwise 0V at output. How can i do so using Op-Amp.

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Guest
Post subject: ComparatorPosted: Wed Oct 05, 2005 3:46 pm
With computers, you can sometimes actually say something like "if the -ve input is -5V" and have it mean something. In the physical, analog world, equality is only a concept - there's always noise, which makes equality testing impossible and essentially meaningless. (For example, what should the circuit do if ve is -5.0000001V? It's not really equal, but it's not very far off, either).

Do you really mean "if the -ve input is less than -5V"?

Please clarify.

Good Luck1

Posted 11/12/2012