hi All,
I am trying to design a comparator where the max voltage on the PCB is limited to 5v.
I am trying to compare an ac voltage when it drops below 32v but not sure how to set the reference voltage. here is a schematic i had come with but not sure how to move forward with a reference voltage. I had designed it after several iterations where the ac voltage was way below 2vac. Now managed to bring the voltage up 30vac. This a a followup from my previous
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the comparator should work like this,
Below 33 - HIGH
Above - LOW
got this when voltage at the primary of the MOT (load) and 26vac when the secondary are shorted.
so 26vac is 16.5vdc and divide it by 5 gives a 3.3v which i guess should be the reference voltage ? and 33vac is 20.9vdc and divide it by 5 is about 4.1v
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the comparator should work like this,
Below 33 - HIGH
Above - LOW
got this when voltage at the primary of the MOT (load) and 26vac when the secondary are shorted.
so 26vac is 16.5vdc and divide it by 5 gives a 3.3v which i guess should be the reference voltage ? and 33vac is 20.9vdc and divide it by 5 is about 4.1v
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Seem to have partially got it, at 26vac vout should read HIGH but its low and at reads LOW above 30, which it does.
