Circuit to substitute switch

[Zordon]

Hi,
I only have normally closed pb switches and i need a switch with a Normally open and Normally closed connection. How can i accomplish this using digital circuitry instead of the correct part using only a normally closed pb.

I was thinking of a Mux but dont know how to approach this project.

 

[Veraxis]

If you want a momentary switch that is triggered electronically, you can use an XOR gate or an XNOR gate for a momentary normally on switch or a momentary normally off switch respectively. If you want them to switch simultaneously, just link them to the same trigger (see file). If you want a toggle switch with an electronic trigger, use a T-latch (see pic.). If you want to turn a normally closed electro-mechanical pushbutton into a normally open one, I guess you could throw a NOT gate in series with it...

 

[crutschow]

Do you need an actual isolated switch contact or just a logic signal of the correct polarity?

 

[Zordon]

Hi, JLNY post has been very helpful but I would need an isolated switch contact so I can have a clock going on the normally closed and a different signal on the normally open connection.

 

[canadaelk]

You are not clear with your description. Is it a SPDT or a DPST or a DPST (alternate action). Why not a litle schematic: In-Switch-Out. E

 

[Zordon]

Sorry im not sure what it is called i guess i need a double pole single throw to have one normally open connection and one normally closed and to alternate when someone presses a normally open pb.

 

[Veraxis]

Sorry im not sure what it is called i guess i need a double pole single throw to have one normally open connection and one normally closed and to alternate when someone presses a normally open pb.

perhaps I am misunderstanding, but wouldn't my original "momentary switch" diagram work for that if you used the pb to control the trigger?

 

[Veraxis]

hang on, I screwed up. the circuit I posted before does not work. This should work, I'm sure this time.