16-bit I²C GPIO expander with POR and interrupt
The PCA9555DBR: It provides 16 configurable I/O pins with push-pull output, a power-on reset (POR) feature, and an interrupt output that signals the host when an input changes state. The 24-SSOP (5.30 mm width) package fits into compact PCB layouts common in industrial control panels, telecom line cards, and sensor aggregation boards. This part is a workhorse for adding digital I/O without burning MCU pins.
The 24-SSOP footprint is a standard 0.209-inch wide body — verify the PCB land pattern against the supplier package drawing before layout, as the 0.65 mm pitch is finer than a standard SOIC.
Output drive — 10 mA source / 25 mA sink
Each I/O can source 10 mA or sink 25 mA. For higher-current loads, plan an external driver stage.
This part is qualified for ongoing production and new design-in without an obsolescence clock.