gEDA-user: powermeter power supply update

[DJ Delorie <dj@xxxxxxxxxxx>]

I promised an update to this, and here it is.

I got the LM25575 eval board and wired it up to the powermeter board's
bulk supply, so I could compare theirs to mine side-by-side (kinda the
whole point, yes?).

A pin-by-pin comparison of the two supplies showed that most pins were
acting the same, except one - the FB pin (feedback - it's the output
of the error comparison amplifier) had a clocked signal on it on my
board, but was a steady DC on theirs.  None of the nearby pins had a
clock on it, the solder joint was good, the PDF showed no reason why
there would be a clock on it.  Diagnosis: bad chip.

So, I replaced the chip with the new one I had ordered.  Now it works
fine.

As an aside - the ENC28J60, R8C, FTDI232R, and two ADE7753 chips, use
a total of 164 mA.  The board holds 16 ADEs so 14 x 5 mA is another 70
mA, total 235 mA - well short of the expected 600 mA worst case.  The
ENC28J60 is spec'd at 250 mA all by itself.


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