One other thing I forgot to mention, you can also have losses directly with=
in the H-bridge itself, many have shoot-through current (internal short cir=
cuit) during transitions, due to turn-off usually being longer than turn-on=
.. That happens with both ON/brake and ON/ON methods of PWM but not ON/Hi-Z.=
 Most microcontrollers with multiple PWM outputs have deadband adjustable o=
r programmed in to prevent this, and some H-bridge chips also have shoot-th=
rough protection.

Bob
--=20
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