NXP PCA9539PW,118 - 16-bit I2C-bus and SMBus Low Power I/O Port with Interrupt

The PCA9539PW,118 is a robust, 16-bit General Purpose Input/Output (GPIO) expander with interrupt capability, designed by NXP Semiconductors to provide additional I/O ports for microcontrollers over the I2C-bus and SMBus. This versatile component is housed in a TSSOP-24 package and is particularly suitable for applications where I/O pins on the microcontroller are limited.

With its two 8-bit Configuration, Input, Output, and Polarity Inversion registers, the PCA9539PW,118 allows for extensive flexibility in I/O interfacing. Each I/O port can be configured as an input or output without the need for external pull-up resistors, thanks to the built-in weak pull-up resistors. This makes it an ideal choice for expanding the I/O capabilities of a microcontroller in a wide range of applications, including servers, personal electronics, and industrial control systems.

The device operates over a power supply range of 2.3V to 5.5V, which makes it compatible with both 3.3V and 5V logic levels, thus offering a versatile solution for mixed-voltage systems. The PCA9539PW,118 also boasts low standby current, which is crucial for power-sensitive applications.

One of the key features of the PCA9539PW,118 is its interrupt output that can be connected to the interrupt logic of the host microcontroller. When any input state differs from its corresponding Input Port register state, the device generates an interrupt signal, thereby informing the host controller of the change in input without the need for constant polling, thus saving valuable processor time and reducing power consumption.

The PCA9539PW,118 supports both the I2C-bus Fast mode and the SMBus with speeds up to 400 kHz, providing a high-speed interface for communicating with the host controller. It also includes an active LOW reset input which enables the host controller to reset the I/O expander at any time, ensuring a reliable and predictable initialization.

Overall, the NXP PCA9539PW,118 is a practical and efficient solution for system designers looking to expand the I/O capabilities of their microcontroller-based systems, without compromising on performance or power consumption.