LNK306, input circuitry burns
Hello! We have a schematics based on LNK306. This circuit is connected after PFC. From time to time on some PCBs R1 and C2 are exploding at power-up, at that all other circuitry remains OK. Can it be caused by too low value of C2 capacitor? Thank you!
Comments
OK, thanks. It seems to be like you have said. Can you please recommend the type of the capacitor?
Let's say, what ripple current it shall withstand for worst case?
I believe the following RDK131 and DER231 can help you. PLS find them in the following LINK.
http://www.powerint.com/sites/default/files/PDFFiles/rdr131.pdf
http://www.powerint.com/sites/default/files/PDFFiles/der231.pdf
Great, thanks. Can you please tell me, can we use R1 without C2 at all, if we circuit powered by DC? Or C2 is required for IC itself?
You have to use C2 to handle the huge AC current at input..
It is very possible that the C2 damaged first, and then R1 blew up. PLS try a bigger capacitor for C2. As you know, the input current of buck converter is a pulse, and thus the capacitance and ESR of C2 are very important. Try a bigger capacitor, and maybe it really works.