[sdiy] IC ID

[Tim Stinchcombe]

Hi Scott,

> I'm trying to ID an IC.  ST is the manufacturer, and it's 
> labeled AE P348
> 
> It's only got 2 leads, but is definitely got a polarity and 
> it's not a cap or resistor.

If it is a small square'ish SMT package (4mm x 3mm), my guess would be some
sort of 'transient voltage suppressor'
(TVS)/tranzorb/zener/whatever-you-want-to-call-it (ST call them
'transil'?!), perhaps something like this (?):

http://www.st.com/stonline/products/literature/ds/5544/smaj.pdf

which does come in one flavour with an 'AE' marking on it, the SMAJ5.0A-TR,
which is a 5V unidirectional device. (There is actually quite a good
representation of the markings in that datasheet, including a 'location' and
'date code' - could that be the 'P348'?) If it is one of these, and is
unidirectional, you should be able to see a typical diode-drop on it with a
DVM (the good one that is!). And it could be that the one that is smokin'
has broken down and is merely shorting the 5V rail to ground...

Tim
__________________________________________________________
Tim Stinchcombe 

Cheltenham, Glos, UK
email: tim102 at tstinchcombe.freeserve.co.uk