On Wed, 16 May 2012 12:34:31 +0100, "N_Cook" put
finger to keyboard and composed:

I checked the pcb traces and pins 1 and 4 are swapped over on that schematic
, the 270K dropper agrees but ground and supply are swapped so pinning
agreement with those IR... ones

If you measure the Vcc of the IC, then that should narrow down the
suitable candidates. Vcc is determined by an internal zener, not by
the external components. It doesn't sound like this IC is the problem,
though.

- Franc Zabkar
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