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Gain problem 741 op-amp simulation

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flat5

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I'm playing with Electronic Design Studio version 3.
I have found some bugs with the drawing part of the program but
I'm wondering about the Spice module.
I expected a gain of 10 and am getting a gain of 2 in the simulator.
Also the output voltage is centered on zero volts and is going 1 volt negative.
I'm powering the circuit with one 9 volt battery.
I'm using 30Hz 1 volt input for now to see the output clearly.

The + input is the lower one. Signal is going to the - input.

circuit
http://s1.simpload.com/1113491cc5c1698bc.gif

spice
http://s1.simpload.com/1113491cc5f4baf9c.gif

comments? Have I drawn the circuit wrong?
 
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The lousy old 741 opamp is spec'd with a 30V supply. Some don't work when the supply is less than 12V. Your supply is only 9V.

I think your Spice is looking at the input and not the output.
If the 741 opamp works then its output will be a square-wave of about 6.6V p-p.
 
Thank you for your comments.

"I think your Spice is looking at the input and not the output."

You are right in that the probe is seeing the signal through R4 and R3.
I put another resistor from R3 to ground (110k) and then the sim. said +- .5 volt.

I changed the battery to 15 volts, then 35 volts, then 1 volt.
The sim. still said +-0.5 volt.
Then changed the op-amp to MC1458. Still no change.

It looks to me that the sim. just does not work with op-amps out of the box.
I would have to set up the sim. parameters for every op-amp.

Can someone confirm that this program, as is, does not handel op-amp simulation?
 
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Your schematic does not have the op amp power supply pins connected to the battery.
 
Thank you Roff, that may be important but there is no provision to include them on any IC in the database of this program. I must conclude that they are implied or the simulator is useless!

which it seems to be :)

I also can not get a 2n2222 phase shift oscillator to simulate.
 
Why don't you try LTspice? You will have to import a model for the 741, but it will have explicit power pins, and your circuit will simulate correctly. LTspice is free. There are no limitations like you find in demo and student versions of other programs.
I can show you how to add the model and run a simulation.
 
Now we're talking :)
I will DL the program and play with it.
Thank you very much, Roff.
I will let you know how things come out.
 
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