PCA9548-BB is an octal bi-directional translating I2C switch. The SCL/SDA upstream pair fans out to 8 downstream pairs. PCA9548-BB device splits a single I2C bus into several sub-branches so that an I2C master can select an address of any device without conflict. The system master can reset the PCA9548-BB in the event of a timeout or improper operation by asserting a low RESET input. The power-on reset deselects all channels and initializes the I2C bus state machine. Asserting RESET causes initialization of same channel to occur without powering down the other channels. The pass gates of the switch are designed to limit the maximum logic high voltage at V_CC pin. This allows the use of different bus voltages on each pair, hence 1.8V or 2.5V or 3.3V devices can directly communicate with 5V devices. External pull-up resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5V tolerant.

Features

• 1:8 bidirectional translating switch
• Three address pins allowing eight PCA9548-BB to be connected on the same I2C bus
• Power-up with all switch channels deselected
• Allows voltage level translation between 1.8V, 2.5V, 3.3V and 5V buses
• 5V tolerant inputs