On Fri, 8 Feb 2002, Spehro Pefhany wrote:
> You shouldn't have any diode drops involved. Remember MOSFETs conduct in
> either direction when ON. In the simple case (one MOSFET/PWM) you just add
> another MOSFET in parallel with the motor and drive it out of phase.

Not that simple. You can't just short the motor out, it'll start braking.
So you have to decide "how long", that's the sticky point.

Also, this is not the simple case with one mosfet, it's a full h-bridge.

Theoretically, though, it's the thing to do :) In practice, almost nobody
does it just to save a portion of a diode drop.

Cheers,

Bob

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