Electronics simulation software.

[Arnak]

Hi,

Can anyone tell me of a relatively cheap or free Electronics simulation software that can simulate a touch sensitive switch?

The problem seems to be that while most software can simulate the circuit they do not have an option to simulate a finger pressing a metallic pad 8-((

Thanks for any help that you can give.

Arnak

 

[ikalogic]

Honnestly i never saw such a software (i dont say that it doesn't exist)

I think it would be easier to explain to us the problem and let us help you to imagine the different possible results.

 

[Arnak]

Touch Switch

Hi,

OK, I need to construct a touch switch circuit to use on an organ stop tab.

The circuit needs to be activated by a finger touch and latch on then another touch plate to latch off.

Operating voltage is not critical.

Obviously price is a major consideration as I need to build 190 of the switches!!!

Any advice you can give would be most useful.

Thanks,

Arnak

 

[Nigel Goodwin]

My only advice would be to use proper switches, touch switches have never been known for being reliable - I doubt you would ever get all 190 working at the same time!.

 

[Arnak]

Touch Switch

Hi,

In a normal situation normal switches would be the best idea, I agree.

Using them on an organ is a very different situation as you also need to include settable pistons which can set several tabs at once and a general cancel to set all tabs to off.

I do appreciate that it is a difficult problem but there are commercial designs to do this but they are quite expensive. 8-((

One way that has been suggested to emulate the touch contacts is to use a switch and a 150pf capacitor to ground as the on connection and the same for the off, so in theory any reasonable emulation software should allow this.

I find it difficult as some of the demo software doesn't allow many components or allow much circuit testing.

If I can find a good piece of software at a reasonable price I will buy it and have a play around.

Arnak

 

[Sceadwian]

ltspice is free, but you have to define what you mean by components? Like various different IC's? You generally don't try to simulate them all in one go, you modularize the various circuit stages you're testing and simulate each stage independently, using the input or output from one stage to feed the next as it's behavior is characterized. More detail about the circuit you're trying to simulate, the components involved and exactly what you're trying to achieve would be nice. You could start with what kind of output the switches you're using produce. Because if it's truly analog (touch sensitive) then you're not talking about a switch per say.

 

[Arnak]

Touch switch

Hi,

I have tried some demo software that has components already set up, you can adjust their parameters.

Checking around I think that a 4013 flip-flop would do the job with two momentary switches.

One switch would operate when the tab is pressed down and another when the tab is returned to the up position.

When on the output goes high and low when it is off.

There is scanner hardware available to scan the tabs for a voltage change at the output.

I have found a circuit that looks like it will do the job, now I'd just like to emulate it and test it.

That would alleviate the need for a touch sensitive switch although it is not ideal as it requires a moving tab, ideally a touch switch would turn the 4016 on and off and light a led to show the switch state.

Arnak