Original poster: Finn Hammer <f-h-at-c.dk>
All,
In a SSTC H-bridge, the internal freewheeling diode of the MOSFET is
disabled by a clever arrangement of external diodes.
A schottkey diode above the drain keeps the internal diode from getting
forward biased, so that an ultrafast recovery external diode can provide
the path of any reverse EMF from the load.
Any current passing trough the MOSFET must pass trough the schottkey
diode.
In a typical design, I see MOSFETS capable of handling 20A continous,
with a 3 A schottkey diode on top.
Why is the schottkey diode not dimentioned for a similar 20A?
Cheers, Finn Hammer
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