From: christopher@librehacker.com   
      
   >>>   
   >>> 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   
      
   --- SoupGate-Win32 v1.05   
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