- Joined Feb 22, 2015
D1/C1 absorb the positive-going flyback from the inductor - in fact, that's fundamental to the operation of the circuit.could have two reasons
a:coil has no diode negative pulse could destroy s d junction
b:gate is blown up voltage to high also missing a small resistor to gate >=100Ohm)
The input cap gate is at high freq a low impedance absorbing current resistor will limit this.
It's not shown in the schematic for simplicity, but in fact I have a 2 ohm resistor in series with the gate. The driving circuit is an MIC4452YM, theoretically capable of supplying 12 amps peak.