The NXP PCA9554ADB is an 8-bit I/O expander designed for I²C and SMBus applications, providing 8 general-purpose I/O pins controlled via a two-wire serial interface. The device includes a Power-On Reset (POR) feature that initializes the I/O pins as inputs, and an interrupt output signals the host when an input state changes, reducing polling overhead.
Industrial temperature range and 400 kHz clock — fit for factory and outdoor gear
The 400 kHz I²C clock frequency matches Fast-mode I²C, so it works directly with most microcontrollers without needing to stretch clock cycles.
For dual-sourcing or alternate packaging, the PCA9554ADBR (same die, Tape & Reel) is the reeled variant — the only difference is the shipping medium.
16-SSOP package — surface-mount footprint for compact boards
The I/O current capability is 10 mA source / 25 mA sink per pin, enough to drive LEDs directly or interface with optocouplers without a buffer stage.