MPR121 Touch Controller Breakout, 12 Channels, I2C

Expand your project with touch sensors using the MPR121 touch controller breakout board. The MPR121 chipset uses I2C to connect to your microcontroller like Arduino or Raspberry Pi and doesn’t need any further GPIOs. In fact it’s not only a controller for inputs but also offers simple outputs on the pins 4 to 11 which can be used to drive LEDs.
Select one of four I2C addresses simply by connecting the ADD pin to GND, VCC, SDA or SCL. You can connect up to four breakout boards which means up to 48 touch sensor to a single I2C bus. Following I2C addresses are available:

GND on ADD: 0x5A
3.3V on ADD: 0x5B
SDA on ADD: 0x5C
SCL on ADD: 0x5D

Please note that the breakout board doesn’t offer any voltage regulation, so make sure that you limit the operating voltage to 3.6 V max. Nevertheless, you can still use this board with your 5V Arduino board. Simply use the 3.3 V line of your Arduino to power this breakout, SDA and SCL can be connected directly to your Arduino and your ready to go.