Multisim and Ultiboard

cancel
Showing results for 
Search instead for 
Did you mean: 

Integrator output larger than supply rails

Hello 

 

I tried to simulate a simple integrator circuit with a CA3140M op-amp using +/-5V rail supplies. The output is measured as high as 1.6 kV for input sine signal as small as 100mV pk at 500 Hz. Can someone explain this surprising issue? This does not happen with a 741 op-amp in the same circuit.

Thanks for your advice

0 Kudos
Message 1 of 3
(990 Views)

Hello,

 

if you double click on the opamp and then Edit Model you'll see that it is a very simple AC model with controlled sources. There is no output swing limitation, non-linearity, SR or other large signal behavior described. This means that you can only do small signal AC runs with your circuit unless you find a more complete model of the opamp. This typically depends on the IC manufacturer. The AC sweep runs as it should for the lossless integrator.

 

0 Kudos
Message 2 of 3
(925 Views)

Thanks Gabor for your valuable input

0 Kudos
Message 3 of 3
(884 Views)