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Help with LM741 op-amp? Answered

Just to test it out, I hooked up a voltage follower with a LM741 Op-amp. But, when I measure the voltages, it doesn't work.
When I have problems with such simple circuits, it makes me want to kick a small animal.
Please, save the small animals, help me with my circuit.

When I measure Vout, I expected something somewhere around 7-8 volts, but I'm actually getting 13-14 volts.
I also tried changing the resistors in the voltage divider, but the output did not change.
I'm getting my power from an unregulated 12v 1A wall transformer, but I measured it at around 15v unloaded.
I replaced the chip once to rule out static electricity as the problem, and I got an output 0.1 volt higher.
Any ideas?


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Best Answer 8 years ago

No kicking my doggie :)

Circuit is correct...
Check your pin numbers.



Answer 8 years ago

I uhh...
I had the uhhh....
I... had the positive and negative reversed...
I'm going to to cry now.

...thank you


8 years ago

looks like you forgot to connect the wire from OUTPUT back to the MINUS input. This connection sets your GAIN. If the connection is missing or not connected, then the gain will be very high and you will have full volts at output pin. With the direct connection back to the minus input, you should have a gain of ONE. This can also happen if the 1k resistors are not connected to ground. This would make the input at pin (+) equal Vcc 15v and the output will be high. So check to see if you have 1/2 vcc at the (+) input.