Is there a simulatable SPST switch somewhere?

Schematic Simulation (Ngspice)
1

I’m new to KiCad simulator (but not spice). I seem to find most of the standard components i need for simple simulations with the exception of a SPST type switch. Is there one available that I’m just not seeing?

Thanks

2

A long time back when I was using much older (80s) spice I recall using a pwl definition on a resistor from near-short to near-open values, or some simple trick like that.

3

The example below is taken from a thread for KiCad 7.99 (ngSpice 41) but I guess this part of it has been the same for a long time.

image

Source:

Edit: The most important thing here is probably to realize that circuit elements can be changed by formulas, the “time” parameter or other things. That is probably much more convenient in a lot of simulations than emulating a “real” switch.

4

The switch shown above is controlled by the simulation time.

Another approach is the electrically controlled switch, used in the same thread as cited above by paulvdh. If you look for the ugly symbol (a relay), you will find the switch model in the zipped project.

5

Are you looking for a simulation of an actual physical switch with contact bounce?

6

I’m not looking to simulate contact bounce, just the changing of the resistance in a way that doesn’t cause the simulation to struggle with convergence

7

Thank you for that idea on a time dependent resistor. That works!

8

Don’t blame it on me. It’s all Holgers fault. I just copied it from his example thread.

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