|
Snubbers
I believe I used the same maxim app note when playing around with snubbers on my charger power section. This was before I realized that the ringing was due to the parasitic inductance of the input wiring and that it needed to be minimized to reduce the ringing.
Anyway, I hacked together an RCD snubber from spare parts and it eliminated the ~3 MHz ringing on the Drain-Source voltage and reduced the initial voltage spike. Once I redid the wiring and reduced the parasitic inductance, there was virtually no ringing and only a very little voltage spike so I saw no need to add the RCD snubber back in.
Paul, I believe you've already minimized the parasitic inductance with the power board layout... are you having problems or being proactive about EMI?
Oh, I also came across 'snubber' capacitors when I was researching snubber circuits. I believe are designed as a very low ESR low value cap that can handle the rapid full charge/discharge it'd see.
|