Keypad Decoder and I/O Port Expander Features: 16-element FIFO for event recording 10 configurable I/Os allowing for such functions as: Keypad decoding for a matrix of up to 5 × 5 Key press/release interrupts See datasheet for additional features I2C interface with Fast-mode plus (Fm+) support of up to 1 MHz Open-drain interrupt output 16-ball WLCSP, 1.59 mm × 1.59 mm