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I am working on a wall mounted feature that has LED strip lights to create up lighting. I have already created a circuit that dims the lights for power up and off, I just now need to create a circuit that puts 12v to the dimming circuit by touching a single metal plate. I created a circuit similar to this with a 555 timer, but touching the plate makes the power going on until the capacitor is discharged. This circuit is on only, I would like on and off with no time limit, so basically a bi-stable flip flop correct or single input latching circuit? I am a complete amateur in this stuff, so any help would be much appreciated!

Thank you!

http://electroschematics.com/5996/touch-switch-circuits/

http://www.semtech.com/images/datasheet/sx8646.pdf

Thank you for your help, Signality. Unfortunately those circuits all have a touch sensor that completes a circuit, I was trying to figure out a touch sensor that just uses the extra voltage from a person and only one sensor. Can the 8646 do this?

"Can the 8646 do this?"

Yes but it's a very complex chip just to turn a light on and off.

25 years ago, Plessey made a chip that was used in lamps that you touched to turn on, touched to turn on and touched and held to ramp the light up and down. Let go and it held the light level at that point in the ramp. Touch off, touch on and it came back on at the same light level.

Maybe unsurprisingly, I can find no online reference to it or how it worked or anything similar.

However ...

This might help:

:)

Wow, this may be a bit over my head, I really appreciate your help on this though. I really wish that chip was available.. I will probably have to go to two touch sensors unfortunately.

Probably not much help but the example is a generic design using opamps for simplicity. You can use discrete transistors but if the generic design is over your head then a discrete design may be even further.

Take a copy, have play with it and see what you can learn from it.

Have a look at:

https://www.circuitlab.com/forums/basic-electronics/topic/bf37fy6t/some-useful-learning-resources/

:)