How to add this functionality into a circuit:

[BassBomb]

I've got some LED, Op-amp, resistor network circuit that is to be controlled by two switches

Basically one power source is amplified by op amps and then that signal drives the LED's.

What I want to do is have two switches which control this power souce:

If only one of either switch is on I would want the power source to be interrupted
If they are both on or off I would want the power source to be allowed through

As you can see this sounds like an XNOR gate, but I don't know if you can simply use XNOR CMOS logic into a normal circuit like mine.

Does anyone know a nice way to make this work out?

 

[40sTheme]

Why not have one switch? Any particular reason?

 

[Red Squirrel]

Sounds almost like a 3 way circuit, but not quite. Maybe use a 3 way circuit, and just flip one of the switches around so it's off when really it's on? 😛 Not sure if they make 3 way dip switches though (I'm assuming that's what you're using)

 

[BassBomb]

Why not have one switch? Any particular reason?

The whole point is to have two modes:

One mode lights are always on until Switch A is pressed
(Switch B remains in on position in this case)

Other mode is lights are always off until Switch A is pressed
(Switch B remains off in this position)

Does that make sense?

@ RedSq
One switch can be a simple Dip switch (Switch B), but Switch A needs to be something that is fast like a micro-switch 1P2T

 

[40sTheme]

The whole point is to have two modes:

One mode lights are always on until Switch A is pressed
(Switch B remains in on position in this case)

Other mode is lights are always off until Switch A is pressed
(Switch B remains off in this position)

Does that make sense?

Ah ok.
RedSquirrels post should work I think.

 

[Dumac]

Sounds almost like a 3 way circuit, but not quite. Maybe use a 3 way circuit, and just flip one of the switches around so it's off when really it's on? 😛 Not sure if they make 3 way dip switches though (I'm assuming that's what you're using)

I remember having to come up with this design in physics lab.

 

[BassBomb]

Thanks RedSquirrel

That will definitely work for me!

I spent ages trying to figure out what the third pin on the microswitch was for...

 

[Matthiasa]

Honestly I would just use the logic gate, might have to do something to regulate the voltages to it, but the output could just be sent to another op amp to get to whatever voltage you want.

That does depend on what voltage the logic gate operates at though, but it should work if voltages are set properly.

 

[BassBomb]

Honestly I would just use the logic gate, might have to do something to regulate the voltages to it, but the output could just be sent to another op amp to get to whatever voltage you want.

That does depend on what voltage the logic gate operates at though, but it should work if voltages are set properly.

I think it is far simpler to just have our switches arranged in this fashion. Less clutter and less we need to power and wire.

 

[Matthiasa]

Yeah probably. 😛