You pose a good point about knock off chips. I'll keep that one in
mind whenever I purchase parts through part miner.

Is this a new circuit you are using the IAMP in? I'm sure you ruled
out all other possibilities before coming to the conclusion that it is
indeed the instrument amp.

Please, post how it goes. I'm interested in knowing if the part houses
are passing along forgeries.

cheers

JW wrote:
Hello,

Has anyone seen any lot problems with BB/TI INA118UB instrumentation amps?
http://focus.ti.com/docs/prod/folders/print/ina118.html

We've just received 100 of these devices that we use on the front end of a
A/D and they all appear to be bad. They are marked INA118UB with lot code
0425. We run them from +5VDC power supply, and regardless of their input,
their output is pegged at 4.2VDC. It occurred to me that these could be
forgeries.

Also, they were purchased from Part Miner and it's beginning to look like
they may be putting up a fight with regards to our returning them - has
anyone had problems with this sort of thing with them?

Thanks.