*If* there's no latchup hazard in the opamp. I never pull below ground any pin on those ancient National designs.
: 81R
er
That's not a hazard, it's a feature--crowbar. LM34, right?
Grins, James
Exactly! I like Phil because his knowledge exceeds Jamie's (Maynard's) by several orders of magnitude and he communicates it clearly. I have learned much from him and I suggest Jamie try to do the same.
Well, no wonder that you never learn anything. He is a prolific poster here and provides great information.
Maybe you got some infatuation
Infatuation? Is that your practice word of the day?
I must ask, what is a sit in a stooly? I don't think I've ever done anything like that. It must be something with which you are familiar and I am not.
Well, I've already replied that I would rather learn from Phil than see your junk.
I never pull below ground any pin on those ancient National designs.
More's the pity.
Why? Do you enjoy chips doing weird things, latching up?
If you're not 100% sure where substrate current is going to go, pulling pins below ground is hazardous. LM324, LM339, 4000A cmos, LM35, lots of ADCs and DACS, were notorious. Lots of new designs still have latchup problems; it must be very hard to fix, since so many designs have this hazard.
When you put hundreds, sometimes 1000+ parts on a board, you've got to be paranoid about risk, or it will never work.
Yes. Read the tiny footnotes, and never power them from more than 5 volts.
We're using LM50's lately, because you can pull down to ground safely and still measure -40C.
I meant, obviously, pulling a signal pin of a single-supply chip below its substrate ground.
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