PCA6408A

PCA6408A Low-voltage, 8-bit I2C-bus and SMBus I/O expander with interrupt output, reset, and configuration registers Rev. 1 — 27 September 2012 Product data sheet 1. General description The PCA6408A is an 8-bit general purpose I/O expander that provides remote I/O expansion for most microcontroller families via the I2C-bus interface. NXP I/O expanders provide a simple solution when additional I/Os are needed while keeping interconnections to a minimum, for example, in battery-powered mobile applications for interfacing to sensors, push buttons, keypad, etc. In addition to providing a flexible set of GPIOs, it simplifies interconnection of a processor running at one voltage level to I/O devices operating at a different (usually higher) voltage level. The PCA6408A has built-in level shifting feature that makes these devices extremely flexible in mixed signal environments where communication between incompatible I/O voltages is required. Its wide VDD range of 1.65 V to 5.5 V on the dual power rail allows seamless communications with next-generation low voltage microprocessors and microcontrollers on the interface side (SDA/SCL) and peripherals at a higher voltage on the port side. There are two supply voltages for PCA6408A: VDD(I2C-bus) and VDD(P). VDD(I2C-bus) provides the supply voltage for the interface at the master side (for example, a microcontroller) and the VDD(P) provides the supply for core circuits and Port P. The bidirectional voltage level translation in the PCA...