Description:
This is a breakout board for Freescales MPR121QR2. The MPR121 is a capacitive touch sensor controller driven by an I2C interface.
The can control up to twelve individual electrodes, as well as a simulated thirteenth electrode. The MPR121 also features eight LED driving pins. When these pins are not configured as electrodes, they may be used to drive LEDs.
There a four jumpers on the bottom of the board, all of which are set (closed) by default. An address ties the ADD pin to ground, meaning the default I2C address of the will be 0x5A. If you need to change the address of the (by shorting ADD to a different pin, make sure) you open the first. Jumpers also connect SDA, SCL and the interrupt pin to 10K pull-up resistors. If you dont require the pull-up resistors you can open the jumpers by the trace connecting them.
There is no regulation on the board, so the voltage supplied should be between 2.5 to 3.6VDC. The VREG pin 2.5 and is connected through a 0.1uF capacitor to ground, which means, unless you modify the board, you cant operate the MPR121 in low-supply voltage mode (1.71-2.75VDC).
Package included:
1 xMPR121-Breakout-v12 Proximity Capacitive Touch Sensor Board
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