> Now limiting applied, PWM is reset, but the transformer core
> might not be reset ?)

Manu, I looked at this a little bit when designing motor (BLDC
and stepper) drivers using FETs and found it wasn't too much of
an issue. As BAJ mentioned, comparators are included in most,
if not all, driver ICs to monitor winding current

Joe

----------

Discussion of BJT (can be problematic) vs FET (generally not)

http://www.edaboard.com/thread138849.html

http://www.ti.com/lit/ml/slup126/slup126.pdf

"In a push-pull converter (bridge, half-bridge, PPCT) duty
cycle D can approach 100% at the switching frequency
(always think of D at the switching frequency, not the
transformer frequency). However, it may be necessary to
limit D to less than 90% to allow a current transformer to
self-reset.

Often the control IC limits the duty cycle for several reasons
including allowing time for delays in turning off the switch"
--=20
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