AN469 I2C I_O Ports_V2_Jan_20_2005.pdf

AN469 I2C/SMBus general purpose I/O expanders Rev. 02 — 20 January 2005 Application note Document information Info Content Keywords I2C-bus, I/O expander, GPIO, EEPROM Abstract One of the more common functions of the I2C-bus is to provide additional I/O port capability for a controller without increasing the number of pins on the controller package. Philips Semiconductors offers many different versions of I2C I/O port expanders. The following is a selection guide that provides the designer with an overview of the similarities and important differences of selecting the best port expander for the job. Philips Semiconductors AN469 I2C/SMBus general purpose I/O expanders Revision history Rev Date Description 2Application note (9397 750 14523). Modifications: ? The format of this application note has been redesigned to comply with the new presentation and information standard of Philips Semiconductors. ? Title of application note changed from ‘I2C I/O ports’ to ‘I2C/SMBus general purpose I/O expanders’ ? Newest I2C devices have been added (PCA9534, PCA9535, PCA9536, PCA9537, PCA9538, PCA9539) ? Technical section added: device pinout, architecture overview, programming, RESET, INT, Frequently Asked Questions. 1Application note; initial version.9397 750 14523 ? Koninklijke Philips Electronics N.V. 2005. All rights reserved. Application note Rev. 02 — 20 January 2005 2 of 44 Contact information For additional information, please visit: For sales office addresses, please send an email to: sales.addresses@ Philips Semiconductors AN469 I2C/SMBus general purpose I/O expanders 1. Introduction 1.1 Family overview The Philips family of I2C/SMBus General Purpose parallel Input/Output (GPIO) devices provides a simple solution for application requiring more I/Os. About 20 different devices can be chosen from two sub-families, commonly called ‘quasi bi-directional General Purpose I/Os’ and ‘totem-pole General Purpose I/Os’. Devices can be chosen w