Part Number:UCC28630
Hi guys,
my customer uses UCC28630 in a 50W LED power supply. When measuring grid-bound noise (150kHz-30MHz) they notice some peak noise at 700-750kHz, which they were only able to filter out using a RC-Snubber (Drain MOSFET -> GND-AUX). Choke, suppresion capacitor and switching frequency of the MOSFET help everywhere else but not at the mentioned frequency range.
In previously designed lower power supplies they are seeing the same tendencies.
Is this a known phenomenon and can it be mitigated in different way?
They would like to save the reduction of efficiency caused by RC-Snubbers or prefer to move it to the transformer.
Thank you for your support,
Franz