16-bit I2C/SMBus GPIO expander with POR and push-pull outputs
The NXP PCA9575PW2,118 is a 16-bit general-purpose I/O expander that connects to the host controller via an I2C or SMBus interface running at up to 400 kHz. It provides 16 push-pull I/O lines, a power-on reset (POR) circuit, and an interrupt output to signal the host when input states change. The wide supply range from 1.1 V to 3.6 V lets it bridge low-voltage core logic and higher-voltage peripheral rails in the same design. Typical applications include server motherboards, industrial sensor panels, and portable devices where the MCU lacks enough GPIO pins.
Housed in a 28-lead TSSOP with 0.65 mm pitch and 4.4 mm body width, this is a standard surface-mount package that routes easily on two-layer boards. The 28-TSSOP footprint is shared across several NXP GPIO expander variants, so a layout can accommodate multiple density options with a single PCB pattern.