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Comparator circuit - RF Cafe Forums

Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views. It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if you would like to post something on RF Cafe's Facebook page, please do.

Below are all of the forum threads, including all the responses to the original posts.


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

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