Re: Synchronous rectifier


<supermos@xxxxxxxxx> wrote in message
news:1140413647.305047.7280@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi, I am working on a integrated synchronous rectifier, in which a
comparator sense the Vds of a MOSFET to control the turning on and off
of the MOSFET. So the comparator is a zero-crossing detector. In the
design of the comparator, the offset is well controled to enhance the
efficiency. But in very light load/zero load, there is some
oscillation. Thus my question is: is anyone of you once meet this
instability problem and could anyone give some advice on this?

Thanks...
Eric
The bane of synchronous rectifiers is dead time which occurs at light
load. Select a topology that contains no dead time at light loads.
cheers,
Harry


.

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