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From: Christopher Howard <christopher@librehacker.com>
Newsgroups: sci.electronics.design
Subject: Re: cheap analog square function?
Date: Mon, 16 Feb 2026 13:08:53 -0900
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>>>
>>> Circuit A is the basic squaring concept, relies on modern open-drain
>>> output comparators being pretty good switches to ground. Assumes you
>>> already have a source of sawtooth or triangle waves with defined zero
>>> and peak values in the system.
>>>
>

I had a few follow questions, if you please, regarding the PWM squarer
(circuit A):

- Does this circuit work in quadrant one only? If so, would any slight
  modification of the circuit allow for handling negative input voltages
  also?

- Could you please tell me a little bit more about the low pass filter
  portion of the circuit? Does that particular configuration have a
  name?

-- 
Christopher Howard