What this I²C/SMBus buffer does on the bus
The PCA9518PWR is a specialized interface buffer from Texas Instruments designed for I²C and SMBus applications. It sits between the controller and the bus segments, isolating capacitive load and allowing more devices on the same bus without violating rise-time limits.
Supply rail and package constraints
The 20-TSSOP package with 0.65 mm pitch requires a controlled impedance layout for the SDA/SCL traces; keep stub lengths under 10 mm to avoid reflections on multi-drop buses.