moinmoin

i'm currently building an led light that should be switched on/off with a touch switch using a metal touch plate.

the touch switch should turn the led's on when touched once and off again when touched the second time ......and so on.

3.6v or 3 AAA rechargeable batteries should power the led's and the touch switch.

with this project space is limited as all the electronics (batteries, led's, touch switch circuit) are enclosed into an object the size of a tennis ball.

i have a toggle flip-flop using transistors but need help to make it a touch switch.....555 timer maybe?

i attached the circuit i have but i cannot make sense from it.
if there is a better solution or simpler way .....any suggestions welcome!!!

thanks in advance for your help

m

Attached Images

toggle flip-flop circuit using transistors.jpg (146.6 KB, 20 views)

iONic

This ought to get you started and more...

http://www.electronics-lab.com/projects/sensors/002/
http://www.aaroncake.net/Circuits/touch.asp
http://www.discovercircuits.com/DJ-C...s/fingersw.htm
http://www.uoguelph.ca/~antoon/circ/touch1.html

moinmoin

thanks ...
do you know if any of these circuits work with 3.6v batteries?
thanks m

SnowyDog

At first glance, I think that the circuit in the second link that iONic has suggested should work fine if you use a low-voltage version of the 4011 NAND chip. The Philips (now NXP Semiconductor) website allows you to do a parametric search for such a device.

http://www.standardics.nxp.com/produ....3&levels=CMOS

The circuit in the third link may work at 3.3v without modification depending upon the characteristics of the MOSFET you choose.

SnowyDog

moinmoin

hey
thanks for these suggestions!
the problem i still have is how to make the two parts that have to be touched into one touch plate.
this is essential because i only have one little piece of metal on a plastic surface ....it can't be two!
any suggestions?

regards m