PSA - more bad TL072s

[Laundryroom David]

If you’re troubleshooting a build that involves TL072s, don’t assume the chips are good even if purchased from reputable sources. I built a @szukalski Blue Sheep yesterday that just would not work. I narrowed it down to the ICs. Popped in known good NE5532s and it sounds awesome. The TL072s I was using were either from Digikey or SBP, so it’s def not a dodgy seller. Anyway, carry on building something! Hopefully this note will help somebody’s sanity.

EDIT: I traced this tube of chips back to a Digikey order.

 

[spi]

Did you note the batch ID? I've been collecting bad TL072 batch IDs that I find or get reported . . . .

Known Bad TL072CP Date Codes:
18MDSHY
14AP8NM
07A5L8QM
22ALE3M

I've been paranoid ever since I read this, but never got around to checking ones I had until today. I have two with code 07A5LQM. Just one character less from a fake one!

These were in my stash, but I may have used some from the same batch in builds. So far I haven't had any that don't work, but if they were noisy not sure I'd notice.

I think I'm in the clear but the code is suspiciously close.

 

[chris.knudson]

I only get my TL072s from Mouser these days. I'm happy to report that all have been good. Although, you can order them directly from TI if you want to go the safest route.