When to use snubber?

Thread Starter


Joined Dec 27, 2007
Hello Everyone,

Can someone please tell me a scenario when you need a snubber? I will be switching (PWM) 42V into a 50mH coil with a series resistance of 0.8 Ohms between 20-100KHz. I plan on having about 0.1-3A of current through the coil. I have no idea whether or not I will need a snubber.

If one is needed, how does one go about designing one?

Thanks very much!



Joined May 7, 2007
Snubbers are usually used to reduce switching stresses across the switching transistors. They also help reduce EMI. Also if you happen to use bipolar devices for the switching they are used for load line shaping.

What is the switching topology? Is it an off-line PS? Flyback topology often require snubbers since the voltage can be very high.