PMDC motor driver

Thread Starter

amitkatheria

Joined Jul 23, 2021
1
Sir,
I am trying to make a PMDC 20V30A driver and have used the below circuit but it doesn't work and sometimes the MOSFETs get too hot. Please help me.

1627023882943.png
 

Sensacell

Joined Jun 19, 2012
2,889
You realize that the high-side gate drive is derived by a capacitor bootstrap?
If you apply a signal for more than a few seconds without switching, the charge on the high-side will leak off and the upper MOSFET will start to drop out of conduction. (HOT)

Steady-state operation is not possible, you could insert periodic "recharge" cycles to keep the bootstrap caps charged.
 
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