|
I did get voltage spikes and ringing on the rise and falls. They were pretty small, like 3-4 volts or so. The ringing didn't seem to increase in magnitude as the voltage increased if I remember right. I'm about to test the car's version in a couple days, so I'll double check that. One thing that helped with the spikes was putting small (like 0.1uF, 0.01uF, 1uF) MLCC capacitors from the input of the gate driver to ground.
I actually did it in real time just to see how it affected things. It was pretty cool. You could actually see the spike shrink each time I inserted a capacitor, and it would grow when I removed it.
Is the freewheel diode responding too slowly? What's the response time for it? I guess I could look it up. Never mind. hehe. I think you gave the part numbers. Hmm... Could you get away with just a single 150 uH inductor? Have you seen what it looks like with just one of them in the circuit? (are you using 2 of them? I forgot. I guess I can go back and read it in a second. hehe)
|