Help needed - hysteresis comparator. Thanks

[ring119]

hey, everyone, i'm designing a hysteresis comparator (to detect small signal pulse and convert it back to digital data). The schematic is from Allen's notes. But i'm not sure how to look at the result, how to obtain the offset voltage and hysteresis window... All i know is to perform a DC simulation and the result is shown in the attached file. I saw ppl mention about monte-carlo simulation, but i'm still not sure how to do it. Can anyone help me on this? Thanks a lot.

 

[mishu_b]

first I suggest (for a little accuracy more) to replace the Ideal current source with one current mirror ....

for hysteresis you need to run 2 DC simulation from 0 to x(V) (your desire value) and back.

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[ring119]

hi, mishu_b, tks for reply.

I run 2 DC simulations, sweep one input voltage from 0 to Vdd and back, but the results are the same. i can not see the hysteresis window... is there anything i did wrongly? tks again

 

[skowe26]

Hi,
Run transient simulation with one input having a fixed voltage and the other input with a triangular wave.

 

[ring119]

Hi, skowe26. I've got the hyteresis window. Thanks a lot.