Description
The STMPE321 is a 3-channel capacitive touchkey controller. Capacitance measurement is implemented in fully optimized hardware. All 3 I/Os can be configured via an I2C bus to function as either capacitive touchkey, or as GPIOs (general purpose I/O). QFN12 (2.2 x 1.5 mm)

Features
■ Up to 3 GPIOs
■ Up to 3 capacitive touchkey inputs
■ Operating voltage 1.65 - 1.95 V
■ Interrupt output pin
■ I2C interface (1.8 V operation, 3.3 V tolerant)
■ 8 kV HBM ESD protection
■ 40 fF resolution, 128-step capacitance measurement
■ Advanced data filtering (AFS)
■ Environment tracking calibration (ETC)
■ Individually adjustable touch variance (TVR) settings for all channels
■ Adjustable environmental variance (EVR) for optimal calibration
■ Capacitive key sensing capability in 27 µA sleep mode

Applications
■ Mobile phones and smartphones
■ Portable media players
■ Game consoles