PMP4397: What is the function of C11 and R6 ?

Hi,

The calculation for snubber loss is P = C * V^2 * F. A 10nF capacitor at 12Vin and 1.6MHz yields 2.3W. All of the power is being dissipated in the 10ohm resistor. My guess is the 10ohm is heating up the capacitor.

I recommend reducing the snubber capacitor by an order of magnitude to reduce the losses. See the attached snubber design method for redesigning.

I will investigate this reference design to understand why 10nF is recommended. At 1.6MHz and 12Vin this is way too high.

Thanks,

RyanSnubbers - Betten.pptx

Regards,
Ryan

I would reduce to 1nF capacitor and use a 0.25W 100ohm resistor. The snubber design procedure that I sent is the best way to design the snubber.

Thanks,
Ryan