Circuit apparatus for controlling a glazing unit whose transparency is switchable, and switchable glazing assembly, motor vehicle and method for controlling a glazing unit whose transparency is switchable

Abstract

The disclosure relates to a circuit apparatus for controlling a switchable glazing unit. The circuit apparatus has a potential-isolated circuit part configured to generate a periodically alternating drive voltage which has a predetermined first period duration on the glazing unit. The disclosure provides a voltage source, to which the potential-isolated circuit part is connected via a transformer and which is configured to operate the transformer with an AC voltage which has a second period duration shorter than the first period duration, wherein the potential-isolated circuit part is configured to receive the transformed AC voltage from the transformer and, in repeatedly alternating switching phases, to respectively forward only positive half-cycles of the transformed AC voltage to an electrical capacitance of the glazing unit and to forward only negative half-cycles of the transformed AC voltage to an electrical capacitance of the glazing unit by means of a converter device.