About Operational Amplifier?

Hi, I connected UA741 IC to the typical non inverting output config. The amplification seems to be fine. When I give an Input signal of 5 volts I get an out put of 14v. But the problem comes when I bring the input signal to zero the output doesnt fall to zero it remains at about 7 volts. Seems like the... show more Hi, I connected UA741 IC to the typical non inverting output config.

The amplification seems to be fine. When I give an Input signal of 5 volts I get an out put of 14v.

But the problem comes when I bring the input signal to zero the output doesnt fall to zero it remains at about 7 volts.

Seems like the amplifier just adds another 7 volts to the input signal. But, according to the opamp equations ie., for the non-inverting configuration Vout=Vin(1+R1/R2) so theoretically when Vin =0 Vout should also become zero , but this doesnt happen.

I need to connect the microcontroller output amplified by UA741 to control a 12 v relay , but since I cant get 0 o/p I am not able to control the relay.

Please tell me why the Vout remains stuck to 7 volts instead of turning 0.
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