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Replacing SB560 diodes on SMPS Substitution

Question: I have a Vizio M420SL Led smart tv that I recently picked up. It powers on and Vizio boot logo comes up just fine. However, when the logo disappears and the picture should display, it just shows a bunch of flickering red green and blue static shapes (usually boxes). It's not displaying symptoms of a bad panel and I've tested the TCON board both with power applied and removed from the tv and it checks out fine aside from my voltage reads "0" with power. I began to study the power board to begin tracing the problem and noticed 2 diodes (running prallel) with each other are showing open and need to be replaced on the secondary power supply side of the mainboard just before the leads to the mainboard. They are SB560s. My question is, is it possible to replace them with SR560s? I'm still learning diodes and have worked a lot with caps, ICs, and resistors which are pretty easy but for some reason diodes are confusing me!! Is there a difference between a "barrier diode" and a "rectifier diode". Both are 5A 60V diodesand i can't seem to find anything online regarding their compatibility. Also, would a failed diode pushing too much power to the other boards cause this displayed symptom? My thought is an excess of power from the Pboard is discharged through the other components resulting in the static screen colors because it's not "regulating" as it should. But then again, I'm still new to LED TVs. Thanks in advance! I'm rambling on but will sum it up below.


Can I replace SB560 barrier diode with a SR560 rectifier diode on my LED TVs SMPS?

What is the difference between a barrier diode and rectifier diode? And can they be used interchangeably?

Would the failed diodes on the SMPS cause the symptoms I explained above due to failed regulation of voltage?

Also, if I can't use the SR560 in placement of the SB560, is there a "step up" or "step down" diode I could use or where I could find (preferably an all in one site that tells me all diodes with same specs as SB560s and part#s)?

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Just curious on the first point. Why not just replace like for like? Given that they cost $1.529 each (minimum 5 pieces = $7.65)

They were chosen by the manufacturer for a reason and if you cannot get them exactly there are always equivalent replacements available.

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True, I originally planned to replace them like for like but couldn't find any around town or in my scrap bin of old boards. Earliest I was able to have some delivered was a week out. I typically do swap them with identical components I just didn't know if there was an alternative.



This link may be of some help. They say that the SR560 is an equivalent (among some others) but note the disclaimer at the bottom


That is the info I was looking for! Going to save the link for future referencing! Thanks!


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