NXP PCA9554APW,112 - 8-bit I²C-bus and SMBus I/O Expander

The NXP PCA9554APW,112 is a highly integrated 8-bit I/O expander that utilizes the I²C-bus and SMBus serial interface. This versatile chip is designed to provide a simple solution for expanding input/output functionality when additional I/Os are needed for ACPI power switches, sensors, push buttons, LEDs, fans, and other similar devices.

This I/O expander is housed in a TSSOP16 package, which makes it suitable for space-constrained applications. It operates over a broad voltage range from 2.3V to 5.5V, which allows it to support various common logic levels and be compatible with a wide range of microcontrollers and processors.

Featuring eight I/O pins that can be configured as inputs or outputs, the PCA9554APW,112 allows for a significant increase in the I/O capabilities of a microcontroller system. Each I/O can be individually set to a high or low logic level, and the input status of each pin can be read back by the host controller. Additionally, the device includes polarity inversion registers that allow for easy data inversion, simplifying the interface with external circuits.

The PCA9554APW,112 supports both the standard-mode (100kHz) and the fast-mode (400kHz) I²C protocols. This makes it flexible for use in a variety of systems with different performance requirements. The device also incorporates built-in power-on reset and features an interrupt output which can be connected to the interrupt logic of the host microcontroller. This interrupt output is activated when any input state differs from its corresponding input port register state, allowing for efficient detection of input changes without the need for constant polling by the host processor.

Overall, the NXP PCA9554APW,112 is an ideal choice for system designers looking to enhance the I/O capability of their projects, while maintaining a low overhead on the main processor and minimizing PCB space usage.