Franc Zabkar wrote in message
...
On Mon, 27 Jul 2009 08:16:37 +0100, "N_Cook" put
finger to keyboard and composed:

Would a SM transient suppressor have a distinctive package./ overlay
designation?

The ones I've seen on hard drive PCBs are flat rectangular 2-pin
packages. I can't find a circuit reference on the PCB of my Seagate
drive, though.

That said, I'd be surprised to find a TVS diode in a closed system, ie
one where there is little chance of user interference.

I assumed the SM 3+1 lead device was a 3.3V regulator "shorted" between 0
and 5V, logo looks like DN in a circle

Could it be an LDO regulator with an on/off pin?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.


Cold mohmeter checking probably would have worked as about 0.04 ohm across
the defective item. Only 6 diodes it would seem on this board, so i checked,
and one across 0 and 5V. I'd not thought of checking diodes , as why across
5V. So a half size 4148 looking barrel SM "diode", overlay saying D,
directly between the, scalpelled off , leaving now separated 5 and 0 rails.
What to replace it with ? 6V, 7V or 10V suppressor , what is usual? Looking
under a 30x microscope is like seeing canals on mars, can just make out what
looks like a lower case "r" and a smudge. Not the slightest look of distress
to this item. As this pvr was previously intermittant then hopefully nothing
else would have been knocked out.