Abstract: A switching stage includes a first plurality of switches configured to produce an alternating current from a bulk voltage. A transformer has a primary and a plurality of secondaries, the primary configured to receive the alternating current. A second plurality of switches are coupled to a first of the plurality of secondaries through a first resonant filter to provide a first voltage output. A third plurality of switches are coupled to a second of the plurality of secondaries through a second resonant filter to provide a second voltage output, the second voltage output being of opposite polarity to the first voltage output. A controller is configured to control the second plurality of switches and the third plurality of switches according to on-and-off state of the first plurality of switches and criteria including whether an absolute value of the first voltage output or the second voltage output exceeds a reference voltage.

Abstract: A single stage switch mode power converter receives a supply line voltage and a supply line current from a power supply line, and provides one or more regulated output voltages for a load, such as an amplifier. The power converter is operable to regulate the output voltage(s) using a controller that includes a voltage controlled current loop. The controller can enable substantially constant supply line current to be drawn from the power supply line by selectively allowing conduction of the supply line current through the power converter. A power factor of the supply line voltage and the supply line current may be optimized by the controller at medium to high power levels thereby maximizing the power provided to the switch mode power converter from the power supply line. Due to the adaptive nature of the controller, the power converter can operate over a wide range of supply line voltage.