Hi all,

I had this same problem a while ago, but couldn't find the thread. A
bunch of my random Linear Technology ICs have been mysteriously
overheating and failing on the breadboard. These include op-amps and
switching regulators lately. All my PIC micros are still working
perfectly as expected even when "abused" (short-circuited, over-voltage,
transient spikes up to 16V(!) on the supply line, well out of the
filtering capability of the decoupling capacitors...).

But it seems that my LT switching ICs as of late are failing even when I
take care to make sure supply lines are clean. The power supply is a
computer power supply at 5V. Oscilloscope shows good transient response
and smooth output. I made sure to stick plenty of capacitors (ceramic,
electrolytic, and tantalum) on the supply line anyway. After about a few
minutes of use, the IC gets extremely hot to the touch, and stops
switching (fails). The current draw from the chip is 1/10 the rated
maximum, and I'm decoupling all power input and output lines properly.

The op-amps are suffering a similar fate, even though the power supply
voltages (+/- 12V) are well within their rated maxima. The op-amps are
even specified for "indefinite" output short-circuit duration, but this
is causing to them to fail even faster.

Temperature probe reports excess of 100'C.

What could be the problem?
--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.