The ADP5589 is an I/O port expander and keypad matrix decoder designed for QWERTY type phones that require a large keypad matrix and expanded I/O lines. I/O expander ICs are used in mobile platforms ...

Analog Devices, Inc., has introduced a mobile I/O expander and QWERTY keypad controller with ambient light sensing for smart portable devices that require a large keypad matrix and expanded I/O lines.

Using eight digital inputs, this circuit simplifies decoding of the common membrane 4x4 keypad matrix and eliminates the traditional requirement of scanning rows or ...