On Tue, Apr 29, 2025 at 12:08?PM ed breya via groups.io <eb=
[email protected]> wrote:
I think Siggi has called it right if the DCV and ripple on the raw feed to
the 3.6V regulator has not already been confirmed OK or fixed. I thought
though that all the filter caps had been replaced earlier. If not, this
could explain it all. If the C42 has been replaced yet still shows
excessive ripple, there may be an open rectifier ahead of it, which would
make it half-wave with much bigger ripple at line frequency rather than 2f.
That's a good point. Looking at the oscillogram (
/g/TekScopes/photo/296482/3910865), it looks to me that
the period is 10ms, which is double 50Hz?
The only way I can see the signal flat-topping like that is if there's no
(or very little) current drawn from the unregulated rail. Though, as we
don't know the DC level, maybe it's not flat-topping at 0V.
All this being said, this current limiting arrangement seems a little hokey
to me as it's limiting the output of the regulator, while measuring the
combined currents from the rectifier and the unregulated output?
