Electronics Questions & Answers ← browse Q&As

Hi,

I'm new to CircuitLab. I'm just creating a simple circuit on a breadboard, where I've added a momentary push button and some logic gates.

How can I simulate the 2 states of the circuit, without changing the circuit? (ex: replacing the push button with something else)

Ideally I'd like to have 2 graphs, one which shows the output with the button pushed, and the other without.

-John

In your simulation, instead of a push button use a relay driven by a low frequency square wave voltage source. Then the relay contact mimics the push button and you can plot both the voltage source and the output of interest

Thank you Foxx. I guess there are a few options to CHANGE the circuit (thank you for your suggestion), but I have to ask: what purpose does the push-button component serve if we can't use it in a circuit? (not shooting you; hoping CircuitLab would comment)

You can control the PB state (open or closed) by going to build mode, double clicking on the PB and selecting "open" or "closed" in the resulting menu. Then you would have to go back to simulate mode to see the result. I don't know how you would plot this. My suggestion would get the same results but would be simple and easy to plot

I ended up creating a momentary button from 4 timed switches. The effect is as follows:

T1s: button closes
T2s: button opens
T3s: (I change some other timed state)
T4s: button closes
T5s: button opens

Though I felt a little nauseous creating this, it solves my problem. Even this way I wish the timed switches could be automatically resettable or cyclic allowing for repeats. Another idea would be to create a timed button.

If you want to dissociate the "main source" of your circuit from passing through what is the switch, you can use the Mr. Foxx suggestion by putting the clocked signal to a gate of a MOSFET.

I would rather limit the use of the timed switched to a case where I want to investigate something like a rush in current to simulate an initial powering on (part of) a circuit. Although someone else may also have other use for them.