APPLICATION NOTE 4054

Using the MAX7359 for Multifunctional and Gaming Keys on PDAs/Smartphones: A Programming Guide

By: Walter Chen

Abstract: The keypad control properties of cell phone chipsets are often stretched to their limits when an operating system or application needs to detect multiple keypresses (e.g. Ctrl-Alt-Del and gaming controls). The MAX7359 is an ideal add-on key-switch controller for implementing multifunctional and gaming keys on a PDA/smartphone QWERTY keypad. The MAX7359 can be connected to the cell phone chipset through an I²C interface, and simple program coding can be used to select a set of desired features.