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N_Cook N_Cook is offline
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Default SMPS failure query

On 13/04/2014 12:22, John-Del wrote:
On Sunday, April 13, 2014 6:51:40 AM UTC-4, N_Cook wrote:
In a Philips CDR755, year 2000. Working fine previous time of use and

then nothing at the next use. Turned out to be a 1N5406 size package

SB360 3amp 60V shottky diode gone short circuit on the LV side for the

5V rail. No other colateral damage (not tried recording a CD yet but

both decks play) , maybe a very slight discolouration on the anode end

of the diode, could equally be from time of encapsulation. After the Tx

, I would have said probability-wise. about the least likely item to

fail. Original manufacturing flaw that progressed or something to check

for before being certain just an isolated failure? if there was ,say, a

power surge/spikes or something could that cause a failure to that diode

and nothing else? Was it just coincidence there was a water leak , over

electrical equipment elsewhere in the house about the time of this failure.


Don't over think this. Shorted diode, replaced, worked... move on. I see this all the time. If your 5V is stable and the diode runs cool, most likely an isolated failure. If it blows another, then revisit.


I just don't like the idea of coincidences. The roof leak poured over a
music system and filled up the tape deck, at least they junked that .
This was in another room but happened over the same week.