Required Snubber Components value
Hi PI,
we have designed a power supply for 3 phase input with 5v,11A load.
everything works fine except the snubber part (please see attached design),Snubber is getting more heat even at 6A
At 6A Resistor is 100 c,TVS is 72 C and Blocking diode is 80 C .
Please provide Snubber components values for the attached design .
コメント
Hi Easy Peasy,
Please find the attached Drain to source waveform at 1A and 10A .
Lleak=30uH.
Hi Please find Gerber also
| Attachment | サイズ |
|---|---|
| Gerber_3D_view.pdf (193.41 KB) | 193.41 KB |
your basic problem here appears to be that all the power parts are too spread out, either side of the transformer - this adds to the Llk and ringing due to the extra length of the pcb traces, and makes it hard to damp the leading edge spike.
Also you need more snubbing on the main o/p diode (larger C) - check the turn off waveform.
With this board the way it is - and with this transformer - the only option you have is to raise the power handling of the primary snubber - if you want to reduce the ringing.
EP.
Without seeing wave-forms and layout it is difficult to comment, a quick cure is to use two or three resistors to spread the heat, and similarly for TVS (2 in series), and 2 x faster 600V blocking diodes in series (35nS)...