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Heating operational amplifier OP284FSZ-REEL7

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Glebiys:
The second operational amplifier just hung in the air, I understand that this is not good.

Today I purchased another LMC6482AIMX/NOPB op-amp. Soldering it and starting it, it began to heat up very much and the output was only 1V, instead of 12V. It is Rail-To-Rail (input/output), the allowable voltage difference is Vsupply. But its difference was in CMOS technology instead of Bipolar.

Kleinstein:
The LMC6482 has an absolute maximum supply of 16 V. So a +-12 V supply is just too much and can blow the chip.

Unused OPs should be connected in a way they don't cause trouble. For the LM258/358 leaving the inputs open is OK, but this is an exception. Other OPs are usually better connected as a follower and the + input to a neutral level.

Vovk_Z:
TS circuit needs a comparator instead of opamp, I think, so I don't see a reason to change different opamps, if he can put something like LM311, LM2903 instead of.
Because comparators "like" to work with large differential voltage (but not opamps), and without negative feedback.

Kleinstein:
Using an LM258 is no problem - the input stage is actually not that different from am LM393 / LM2903.
There are not that many comparators with rail to rail push pull outputs that work with a +-12V supply. If high speed is not needed an OP may be OK as an alternative.
If just used as a kind of digital level shifter, one could consider a CMOS switch chip like DG419 - though probably a different pin-out.

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