I have 4 boards here (2.05g) which all exhibit the same difficult-to
catch fault. It has been described as 'SCR latchup?' by Guralp.
Just occaisionally, when you power it up, it doesn't start properly,
stays in reset (red LED on) and draws shedloads of current (couple of
amps, limited by PSU). The time I caught it and checked, it was the
CPU that was getting really hot.
Cycle the power and the board works fine.
We saw this once with a board last time I was doing fix-it diagnostics
with ChrisJ at his place, but couple't get the board to do it again.
It only ever seems to happen with a board that hasn't been powered up
for some time, which makes it a right pain to try and track down.
Does anyone have any suggestions as to what the actual fault might be,
what I should check, how to reproduce it, or wether it is generally
hopeless and I should delare them all 'knackered'.
I am guessing it might be something to do with power supply sequencing
of the different CPU voltages?
Wookey
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