Anyone got pin-outs for a pin-outs for the following 6 pin IC:

Motorola
SOC640B
V921

Circa 1988. Not been able to find any info on the 'net :-(

It's in a switchmode PSU that I'm trying to fix; probably some sort of
opto-isolator but it'd be nice to know.

Said PSU is *huge* - about the size of two PC motherboards - so it's going
to take me a while to trace out schematics. Chopper transistors seem good
on a multimeter, as does the bridge on the mains side, and the
primary filter caps *look* healthy and aren't shorted at least. There's a
10 ohm resistor as the first thing on the live input past the fuse which
was blown though (I replaced it with a spare and that immediately blew
too). Looks like something's shorting somewhere when power's applied... (I
hate fixing power supplies!)

any help appreciated!

cheers

Jules