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Need help with Comparator problem

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hayowazzup

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Hi, does anyone know if it is possible to put LM339 comparator into an non-inverting/inverting configuration ( having feedback loop)?

I was wondering in what situation I could use a comparator as an opamp and when I couldn't. and under what circumstances an opamp can be used as a comparator? I am trying to designing a opamp circuit that will have a few hundred kilohertz input signal feeding into it, but don't really understand the differences between them.
 

keith1200rs

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You cannot use a comparator as an opamp - it won't be stable. You can use an opamp as a comparator.

Keith
 

luben111

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Hi
Of course you can put LM339 comparator into an non-inverting/inverting configuration ( having feedback loop) but it's not recommended. Comparators are not designed to work as linear amplifiers and you'll get a lot of distortions. OpAmps are not designed to work in saturation mode (differential voltage on inputs is non zero) but of course you can use them as comparators until you don't violate the input characteristcs.
 

Aritra17

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opamp can be used as a comparator as per circuit diagram
i can't say about this particular ic but a comparator can definitely be used as a differential amplifier
 

keith1200rs

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You CANNOT use a comparator as an opamp. Comparator output stages are designed to be either high or low and not inbetween. The output stage has no defined linear region. It will be unstable i.e. it will oscillate.

Keith
 
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