The PCA9306 device is a dual bidirectional I²C and SMBus voltage-level translator with an enable (EN) input and operates without use of a direction pin. The voltage supply range for V_REF1 is 1.2 V to 3.3 V and the supply range for V_REF2 is 1.8 V to 5.5 V.

The PCA9306 device can also be used to run two buses, one at 400-kHz operating frequency and the other at 100-kHz operating frequency. If the two buses are operating at different frequencies, the 100-kHz bus must be disconnected by using the EN pin when the 400-kHz operation of the main bus is required. If the controller is running at 400 kHz, the maximum system operating frequency may be less than 400 kHz because of the delays added by the level shifter.

In I²C applications, the bus capacitance limit of 400 pF restricts the number of devices and bus length. The capacitive load on both sides of the PCA9306 device must be taken into account when approximating the total load of the system, ensuring the sum of both sides is under 400 pF.

Both the SDA and SCL channels of the PCA9306 device have the same electrical characteristics, and there is minimal deviation from one output to another in voltage or propagation delay. This is a benefit over discrete-transistor voltage-translation solutions, because the fabrication of the switch is symmetrical. The translator provides excellent ESD protection to lower-voltage devices and at the same time protects less-ESD-resistant devices.