Philip Pemberton wrote in
:

On Thu, 10 Jun 2010 11:52:17 +0000, Philip Pemberton wrote:

then replace
the TEA1522P before wasting time with the opto isolator, shunt
regulator, or other unlikely candidate.

Swapped the 1522. PSU still dead, no output or startup.

Suspects are now the opto, the shunt regulator, and the resistors which
measured high.


did you check the ESR of the electrolytics,particularly those around your
IC? I've seen where high-ESR caps kept switchers from starting.
They loaded the IC supply enough that it would not start.
I've also seen where carbon film resistors that charged the "housekeeping"
IC power supply cap had increased in value to the point they were open.

--
Jim Yanik
jyanik
at
localnet
dot com