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PWM Circuit

PWM Circuit

PWM Circuit

if you measure the outputs A and B of a pulse width modulation circuit at zero duty cycle, it will measure equal voltage at A and B outputs with the same duty cycle with respect to ground resulting in 0V.
What will the output will look like please if measured between A and B outputs please.

RE: PWM Circuit

I'm not sure...but a manually adjustable PWM controller might be just the ticket for setting up the heat output of a 120VAC motor anti-condensation heater where only a 240VAC supply is available...


"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: PWM Circuit

You crack me up CR!

At zero duty cycle one of the waveforms will be DC 0V and one will be DC at the rail. You'd see the rail looking across both of them.

That's typical A and B. If you have something else like bipolar outputs you have to spell that out.

Keith Cress
kcress - http://www.flaminsystems.com

RE: PWM Circuit

The question is confusing but if both measure equal and 0V then you should also measure 0V between them. 0% duty cycle means at least one output is off all the time.

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