Capacitive Touch Sensor


#1

Hi I’m building a magnetic stirring device and wanted to add a touch sensor so that as items are placed on the top the motor starts automatically, I’m considering purchasing Adafruit Standalone Momentary Capacitive Touch Sensor Breakout;

I wanted to know if this will work through 4mm of plastic.
If not how could i get another pad
I also wanted to know how to power this board, my input is 12V 1A what would i need to convert this to power the sensor.

Many thanks
J


#2

Through plastic it will work, as I’m playing with it’s big brother the QT1070 and you can (using i2c) configure a lot of options. The touch sensor requires at max 5.5v so would need stepping via a regulator/BEC/seperate power.

Have you got a pad that will trigger the sensor? If your after a simple option, a reed relay and magnet is an option (placement away from your other magnets), and have some have a higher tolerance of voltage so get away with 12v through it.


#3

Many thanks
I’ve ordered the sensor, 5v voltage regulator and transistor a switch for 5v to 12v fan
I’m new to building circuits, if it doesn’t work will have to stick with manual switch :(