Patent attributes
An envelope tracking power supply has a multiple-output DC/DC converter, having an alternating current generating portion and a full rectifying portion. The alternating current generating portion to receive an input voltage and operate at zero voltage switching. A full rectifying portion includes at least one secondary winding and one voltage doubler output. each having a first transistor, and a second transistor, used as rectifier devices to allow currents to flow bi-directionally and sink and source the currents from and to output capacitors to keep their voltage balance. A switch bank selects a desired voltage from series connected capacitors and connects it to an output filter. The switch bank receives an envelope tracking command from the voltage selector and provides a step voltage to the output. The output voltage is changed at switching speed to track a high bandwidth envelope signal.