The polypropylene ones will definitely be stronger and have a lower selfinductance, but that may not be a problem in your application; I'd try the cheap non-pol electrolytic and see if it works :-)Originally Posted by GooeyGus
Senior Member
The polypropylene ones will definitely be stronger and have a lower selfinductance, but that may not be a problem in your application; I'd try the cheap non-pol electrolytic and see if it works :-)
Senior Member
I just found that there are two 1n4935 diodes on each board near the big inductors.
I measured only 4ohms resistance across these diodes, both ways, on both boards. These are 200v 1A diodes. I measured resistance using my DMM... I'm guessing this is an issue?
Senior Member
That depends what's in parallel with them really- can you remove them from the PCB and test them again? They may be essential to the proper operation of the switcher- there'll be a flywheel diode and a rectifier diode in most buck or boost topologies. If the flywheel diode goes, efficiency drops and the chopper transistor eventually fails, but if the rectifier goes the whole thing goes foom.
Senior Member
Yeah you were right... they test fine when removed
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