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Subject: Re: [geda-user] Design suggestions...
From: John Doty <jpd AT noqsi DOT com>
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Date: Wed, 21 Dec 2011 12:16:51 -0700
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On Dec 21, 2011, at 12:09 PM, DJ Delorie wrote:

> 
>> That, and add a little capacitance to the DC motors/potentiometers
>> so PWM of them effectively creates a sigma delta DAC with an output
>> smoothing filter.
> 
> I'd assumed rotor inertia would be sufficient, but I suppose "that
> depends" as usual.
> 

The problem with added capacitance is that it increases the dissipation of the driver, since it then has to charge/discharge the capacitors when it switches. With enough capacitance to smooth the waveform, this will be a big effect.

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd AT noqsi DOT com