LNK304 does not come back after overcurrent

Posted by: Inepro on 11/26/2012

If the LNK304 has a overcurrent its does not restart properly after that current is removed.

It just pulses a bit in a sawtooth pattern but it does not each normal output voltage again.

Is there a way to make it come back without having to discharge the main capacitors?

It is going to be in a always powered on configuration and i don't want it to hang on that forever.

Comments

Could you PLS upload your schematic?

Thanks and best regards

I have added the schematic.

I found that 90V schottky diode is used for your power supply. I wonder if 90V is good enough for your input. Could you advise the input voltage when this issue happen? Or you may try a didoe with higher voltgae rating.

Regards

Input voltage is 230VAC nominal, so about 325VDC, but can reach 400VAC.

I have tested the power supply up to about 560VDC without parts failing.

In the datasheet there is no mention about the voltage that the diode should withstand.

You think that with a higher voltage diode the power supply would recover from overcurrent without a power cycle?

When the LNK304 turn on, the voltage across the didoe could be 560Vdc, and thus the 90V didode must be replaced. The issue maybe solved wiith a higher volateg rating diode. You can use a didoe shown in PI DER report or datasheet.