Touch Controlled LED Canvas

This is a very simple project for people who feel that a basic canvas from wilkos just isn't special enough for you.
This instructable will show you how to brighten up a dull canvas and give it a little more character

Here is a list of the items you will need. The picture above includes paint but if you bought the canvas then you don't need that.

1. Scalpul
2. Soldering iron
3. Solder
4. DUEL AAA Battery Holder (single in the photo)
5. 2x AAA batteries
6. Multi-core wire
7. Hack Saw
8. Adafruit Standalone Toggle Capacitive
9. Touch Sensor Breakout
10. MULTICOMP - MCL914GD - LED, 1.8MM, 76°, GREEN

Other LED's can be used but the ones listed are what were used in this project. They have a forward voltage of 2.2V which is why 2 AAA batteries are needed (1.5V each)
AA batteries could be used for longer battery life if desired but make sure they fit in the frame of the canvas first.
Links for the LED and the Toyuch Sensor are below.

http://www.maplin.co.uk/p/adafruit-standalone-toggle-capacitive-touch-sensor-breakout-n52dq

http://uk.farnell.com/multicomp/mcl914gd/led-1-8mm...

This step show the layout of the circuit in schematic form and in practical form.

The circuit is very simple. Each of the LED is wired in parallel so the positive legs are all wired together and all the negative legs are wired together.

it is good practice to label the wires before soldering them together so i labeled the negative pin of the LEDs with some black electrical tape.

The Touch Switch is slightly different from a standard toggle switch because it required a VDD to power the chip and the output voltage comes from the LED1 pin.

The batteries positive wire connects to the VDD of the touch switch and the ground to the GND pin. The LEDs positive pins are connected to the LED1 output and the negative to the GND wire that the battery is connected to.

Standard calculations are:

20mA per LED
30x LED's
20 X 30 = 600mA

The voltage is constant because it is wired in parallel.

An average single AAA battery will lst 2 hours of continuous draw so 4 hours with two.

1. It is best to do each canvas individually then wire the canvas' together at the end.
2. Use the scalpel to cut a small hole for each LED in the location you wish to place the LEDs
   
   • You could do this before soldering the LEDs to estimate length of wire between links
3. Once the desired number of LEDs are wired together (making sure that one end has 2 extra long wires attached)
4. When all the holes are cut, push the LEDs one-by-one through the canvas making sure that the last LED with the connection wires is at an edge that boarders another canvas.
5. For the battery, it can be placed anywhere that will fit it and it can reach the switch

On the touch switch there is a pin that allows a different sensor to be used rather than the on-board one. A simple piece of foil works.

simply solder a wire to the to the pin and the foil to that and attach the foil to the outside of the canvas. This is demonstrated in the picture above.

The sensor board can be tucked under the frame of the canvas or wherever you see fit.