This brick is used to phase external I²C components into the brick system. It contains two internal voltage sources of 3.3V and 5V and provides internal conversion between 3.3V and 5V I²C for the signal voltages. This allows for three tasks to be accomplished. First, it enables the use of brick components on the common I²C bus that are only offered by the chip manufacturer at 3.3V. The other two functions are the ability to integrate external sensors at both 3.3V and 5V via connection wires into the brick system. Of course, a bridge can also be used here to provide 3.3V and/or 5V as a stable voltage source for small currents.