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Hi, I'm designing an AGC (Automatic Gain Control) circuit with LM741. You can find the schematic (is public) AGC1 from my user "robertomanfredi". The LM741 is supplied with one +5VDC power supply. If you run a DC Simulation it says: V- (pin 2) = 111.1 mV V+ (pin 3) = 2.373V V out (pin 6) = 5.974mV This is impossible because Vout=A*(V+ - V-). Can you help me ? Thanks

Searching for AGC1 does not find your circuit but I found it by clicking on your username.

To help find circuits quickly, it is helpful to post them using the URL or the CL link under the "Link and Share" option.

For A = the open loop gain then

Vout=A*(V+ - V-).

is only true when the amplifier is operating in its linear range.

A real LM741 output can only operate to within a couple of volts of either rail so it will not operate properly from a single 5V supply.

I'm not sure exactly how close to a real 741 the CL model is but if you make V1=15V then V(out) sits at 7.5V which looks more like you'd expect.

Thanks for your comments