I²C/SMBus translating switch for multi-voltage buses
The PCA9548ADW is an 8-channel I²C/SMBus translating switch from Texas Instruments, designed to route upstream bus traffic to one of eight downstream channels while translating between different voltage domains.
Package and board-fit: wide-body SOIC-24
The PCA9548ADW comes in a 24-SOIC package with a 7.50mm body width (0.295"), which is the wide-body variant. This is not the narrow 3.9mm SOIC-24 — the footprint on your PCB must match the wider body, and the tube delivery (not tape-and-reel) means it ships in antistatic tubes for manual or low-volume assembly. Surface-mount assembly is standard, but the wide-body SOIC has a larger pad pitch (1.27mm typical) that is forgiving for rework and inspection compared to finer-pitch packages.
Supply voltage and bus translation range
The translating switch function allows the upstream bus (connected to the master) to run at a different voltage than the downstream channels — for example, a 3.3V master talking to 1.8V I²C peripherals, all through one IC. The interface is I²C and SMBus compatible, so it works with standard I²C masters and SMBus hosts. The 8-channel architecture lets you isolate or enable individual downstream buses, useful for addressing conflicts or power-sequencing multiple sensor clusters.