PWM:

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   Create a model of a pulsewidth modulator using Pad� approximants.

   The pulsewidth is assumed fixed at tau. The function includes the
   sampler gain of 1/tSamp;

   Since version 1.
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   Form:
   [a, b, c, d] = PWM( tau, tSamp, n )
   [num, den]   = PWM( tau, tSamp, n )
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   ------
   Inputs
   ------
   tau           (1,1) Nominal pulsewidth
   tSamp         (1,1) Sampling period
   n             (1,1) Number of terms (optional)

   -------
   Outputs
   -------
   a or num            Numerator polynomial or plant matrix
   b or den            Denominator polynomial or input matrix
   c                   Measurement matrix
   d                   Feedthrough matrix

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Children:

Common: Control/Delay
Common: Control/FResp
Common: Control/ND2SS
Common: Control/ZOH