Re: Bridge Failures ...



"hr(bob) hofmann@xxxxxxx" wrote:

It seems like Graham's been pretty well subdued by most of the
commenters who see a reasonable number of reasons why one diodes on
one side of the bridge might fail more often. Not that it couldn't be
a statistical anomaly, but there are other possibilities too, and I
hope Graham now understands his trashing response was out of line. We
need helpful comments, not trashing ones.

Most of the comments that suggested a relationship seemed to be clutching at
straws quite frankly.

The best explanation I saw was the influence of large areas of copper foil on the
pcb. That will help to cool the diode on that 'leg' and a cool diode is less
likely to fail than a hot one.

However, the idea that there's always more foil on the negative terminal seems
spurious to me. I certainly don't lay out pcbs like that. Your own experience may
differ of course.

Graham

.

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