# Clipper Circuit Calcs .... I sure need help

Discussion in 'The Projects Forum' started by ivan_the_red, Dec 25, 2008.

1. ### ivan_the_red Thread Starter Member

Dec 7, 2008
11
0
I've spent some time trying to find out how to design a clipper clrcuit that will output a square wave signal from 0vdc to 7vdc from an AC input signal that is 12 volts. I have found alot of circuit examples but none of them had any formulas or explainations that I could follow in order to calculate the resistor and Zener diode values.Can anyone show me the calculations needed to accomplish this...please

Thanks
Ivan

Apr 20, 2004
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3. ### ivan_the_red Thread Starter Member

Dec 7, 2008
11
0
Thanks for the quick response, but this is what I was looking at previously and I dont see any calculations for anything. That resource does show basically whats happening, but how do you size the resistor and diode????

4. ### SgtWookie Expert

Jul 17, 2007
22,182
1,728
Well, you'll want to limit the current to keep it from exceeding the diode's ratings.

If you're going to use Zener diodes, you'll need to look up the datasheet(s) for them to see what the minimum current is to guarantee regulation, the maximum current permitted (keeping wattage in mind; derate 10% at least) and size the resistor appropriately.

With a 12VAC signal in, your clipped waveform will be trapezoidal, not a square wave. If you really want a square wave, you'll need to use something like a comparator.