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Understanding op amp circuit

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d4n13l:
Hi,

I'm starting with op amps, from the schematic, I get 0-1V from voltage divider, and I would expect to see the same voltage in the output of the op amp due to the negative feedback but it stays frozen at 1.9V no matter the +IN voltage. Could someone help me figure out why isn't it working?

rstofer:
Check the data sheet.  The op amp probably can’t work within a couple of volts of the rails.

Ultron81:
Yeah, what he rstofer said. If you want the input to drop to 0, you either need to supply a negative supply voltage to the op amp, or use a single-supply op amp that can go to 0V like a LM358.

d4n13l:
It worked with the LM358, I didn't know that not all op-amps can be used like that. Thanks :)

nigelwright7557:

--- Quote from: rstofer on July 24, 2019, 12:19:26 am ---Check the data sheet.  The op amp probably can’t work within a couple of volts of the rails.

--- End quote ---

Try a rail to rail op amp.
Not all op amps work close to the rails.
In fact some invert the output if close to the rails.

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