Re: Flyback Diode

Michael wrote:
Hi,

How do you go about choosing a suitable flyback diode for a 1.8kW 36V motor? Does it have to be able to handle above the motor's stall current of 50A?

You might get by with a smaller diode, but you would have to heat sink it very well to cover the worst case situation. At stall, something approaching 90% of motor current will pass through the diode.
You could parallel the two halves of this one for less than $6 from Digikey:
http://www.irf.com/product-info/datasheets/data/60ctq045pbf.pdf

This one costs twice as much but has more margin (both voltage and current):
http://www.st.com/stonline/products/literature/ds/6728/stps80l60c.pdf
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