MPR121 Breakout V12 Capacitive Touch Sensor Controller Module I2C Keyboard Module
- This
is a breakout board for Freescale's MPR121QR2. The MPR121 is a
capacitive touch sensor controller driven by an I2C interface. The chip
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 jumper ties the ADD pin to ground, meaning the
default I2C address of the chip will be 0x5A. If you need to change the
address of the chip (by shorting ADD to a different pin), make sure you
open the jumper first. Jumpers also cont SDA, SCL and the interrupt pin
to 10k pull-up resistors. If you don't require the pull-up resistors you
can open the jumpers by cutting the trace conting them.
- There
is no regulation on the board, so the voltage supplied should be
between 2.5 and 3.6VDC. The VREG pin is conted through a 0.1uF capacitor
to ground, which means, unless you modify the board, you can't operate
the MPR121 in low-supply voltage mode (1.71-2.75VDC).
- 1pc x MPR121 Breakout V12 Capacitive Touch Sensor Controller Module I2C Keyboard