Introduction
STMPE801 is an eight-bit port expander that can be interfaced to the main digital ASIC or processor via the two-line bidirectional I2C bus. The digital engines in mobile multimedia platforms usually come with a limited number of I/Os. The port expander ICs can be used to increase the number of I/Os or control signals in such applications.

STMPE801 can be used in advanced digital platforms such as:
● Portable media players
● Game consoles
● Mobile phones
● Smart phones etc.

This application note explains the setup and hardware interfacing of the device to the main processor.