US Patent 7245509 Half bridge driver

A half bridge driver includes a push/pull control chip outputting a first control signal and a second control signal. Each duty cycle of the two control signals is smaller than 50%. A driver couples to the push/pull control chip and a DC power for receiving the first control signal and the second control signal. A half bridge switch assembly with two N-MOSes couples to the DC power, the driver and a transformer, and converts the DC power into an AC power by the driver. The AC power is transmitted to a first side of the transformer.