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mike mike is offline
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Default Anybody have a schematic for the SMPS for this laptop?

Robert Macy wrote:
On Nov 4, 11:05 am, mike wrote:
Robert Macy wrote:
Anybody have a schematic for this simple SMPS?
AC to DC Adapter for the IBM Thinkpad T22
16V 3.36A
On the unit itself is
Battery Technology, Inc.
IB-PS365
09000000106991
from that I found:
Battery Technology, Inc.
16500 East Gale Avenue
City of Industry, CA 91745-1712
Tel: 626-336-6878
Fax: 626-336-5657
http://www.batterytech.com
but, they don't answer their phone, nor does their website 'find' any
refrence to this model?!
the 800 number from their own website comes up disontinued.
Anybody have a schematic? Especially interested in the input section
= AC mains up to the rectifiers and fusing.

Don't have the schematic, but tracing out the input part from the board
oughta be trivial.
Anything particular you're trying to determine?


pigtail fuse size [can't read without removing]

any potential parts that may have zapped when the liquid hit it while
powered.


Every thinkpad supply I've seen has been free of vent holes. You'd have
to drop in a puddle and leave it there to get much liquid in.

You gotta take out the fuse to replace it. If it's not marked, you can make
a guess based on the input current numbers on the sticker.

As for failure, when you fill it up with liquid, the input circuit
is not the weakest link. With a new fuse, you should measure continuity
between the input connector and the diodes. Check the diodes.
That's about all you can do.

More likely, liquid got into the switcher and smoked the main switch
transistor blowing the fuse. Check resistance source to drain on the
FET.

Depending on what liquid, how long before it got throughly neutralized
and thoroughly
dried, you may want to find a dumpster.

It's not extremely likely, but if some bit of corrosion grows and causes
the output voltage to increase to levels lethal to the thinkpad, you'll
be looking for a slightly bigger dumpster. If it catches fire and burns
down your house, you'll need a REALLY BIG dumpster.

The risk is critically dependent on whether the liquid was
clean water dried immediately or cat pee left for a month.