The PCA9306 is a dual bidirectional I2C-bus and SMBus voltage-level translator with an enable (EN) input, and is operational from 1.0 V to 3.6 V (Vref(1)) and 1.8 V to 5.5 V (Vbias(ref)(2)).

The PCA9306 allows bidirectional voltage translations between 1.0 V and 5 V without the use of a direction pin. The low ON-state resistance (Ron) of the switch allows connections to be made with minimal propagation delay. When EN is HIGH, the translator switch is on, and the SCL1 and SDA1 I/O are connected to the SCL2 and SDA2 I/O, respectively, allowing bidirectional data flow between ports. When EN is LOW, the translator switch is off, and a high-impedance state exists between ports.

The PCA9306 is not a bus buffer like the PCA9509 or PCA9517A that provide both level translation and physically isolate the capacitance to either side of the bus when both sides are connected. The PCA9306 only isolates both sides when the device is disabled and provides voltage level translation when active.