MPR121 12-Channel Capacitive Touch Sensor

MPR121 12-Channel Capacitive Touch Controller Breakout

The Freescale MPR121 controls up to 12 individual capacitive touch electrodes over an I2C bus. Featuring internal hardware filtering and automatic baseline calibration, it turns any conductive material—copper tape, fruit, water, metal plates—into an interactive capacitive keyboard.

Specifications

• Electrode Channels: 12 independent capacitive touch inputs
• Interface: I2C with configurable addresses (0x5A to 0x5D)
• Operating Voltage: 2.5V to 3.6V (onboard 3.3V LDO regulator included)
• Interrupt Pin: Active-low IRQ triggers immediately upon electrode touch/release
• Internal Filtering: 8-stage automatic baseline tracking against environmental changes
• Applications: Custom keypads, touch sliders, interactive installations