I have attached a comparator circuit. I want to add hysterisis on non-inverting input. How can I do that?

 

Here is a link to an article from Maxim - http://www.maxim-ic.com/app-notes/index.mvp/id/3616

And Analog Devices - http://www.analog.com/library/analogDialogue/archives/34-07/comparators/

 

Welcome to the forums.

When you post a circuit, we'd appreciate a picture file - such as png, pdf, pict, etc. - as opposed to a Word doc. It's much faster to take a peek.

Have you read the datasheet for a comparator, such as LM339? They will usually include an example of applying hysteresis

 

thanks alot

 

How can i increase the switching speed of this circuit?

 

How can i increase the switching speed of this circuit?

Feed it a faster signal?

You need to supply a LOT more info for anyone to help you. You haven't specified any parts or circuit details. How do you know you need faster switching? What are you really trying to do?

 

Increase the speed of WHICH circuit? You need to post a schematic of which circuit you are talking about, preferably in .PNG format.

 

Sorry. I have attached the circuit now. The inverting input changes at a slow rate and the output of opamp changes in the form of ramp. I want to decrease the time it takes to change levels.

 

Try it like this instead.

See the attached.

 

Also using a dedicated comparator(393 or 339) will do away with the ramp on the output. Output will be a square wave, and will work with a single rail supply.

 

Those comparators require a pull-up resistor, as their outputs are open-collector.

Pull-up Ohms ~= Vcc/4mA

 

thanks a lot for the help