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I'm trying to simulate a quad op-amp with KiCad. As an example, I chose the LM324.

The tutorials don't show how a quad op-amp is simulated. They show a single op-amp, a diode, or simple RC circuits.

I first drew this schematic:

enter image description here

U1A, U1B, U1C, U1D and U1E are op-amps and the supply pins of a quad op-amp model.

VDC and VSIN above are SPICE simulation symbols of KiCad.

For the quad op-amp (LM324) I chose this SPICE model. I saved this with the .lib extension (lm334.lib) in the project folder. Then I double-clicked on U1A and used the SPICE model editor by pointing at the SPICE file and chancing the "Alternate node sequence" 3,2,4,11,1 as follows. This is because the SPICE pin names are different from KiCad's. Then I clicked OK.

U1A

I did the same thing for U1B using the same SPICE file and changing the pin sequence:

U1B

I did similar steps for U1C, U1D and for U1E (for the supply pins). I set the pin sequence as follows as in U1A:

enter image description here

When I click on any U1 they are all the last alternate pin sequence. When I run the simulation with the following settings (or any SPICE settings):

enter image description here

The simulation doesn't work as expected. I get "Error: vector V(Out) not found."

How can a quad op-amp (given its SPICE file) as in my question be simulated properly in KiCad? I don't want to use single op-amps because that doesn't make sense since this will go on a PCB in the second stage.

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1 Answer 1

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Unfortunately, there's no simple way to solve this. If you're comfortable with creating a simple SPICE subcircuit in text, you should be able to follow Section 8 (Using a Dual OpAmp) of the following instructional article and apply it to a quad opamp:

https://ngspice.sourceforge.io/ngspice-eeschema.html#multi

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