US Patent 10159524 High power battery powered RF amplifier topology

The design of high-power RF amplifiers, specifically the design of the output transformer, is complicated by the relatively low voltage provided by battery packs that are practical for handheld devices meant for possibly delicate uses. Provided is an RF amplifier with one or more taps on the primary coil, wherein each tap is controlled by a half bridge driver. The output transformer primary winding may be driven between any two half bridge drivers, with the number of turns between the half bridge drivers and the fixed output winding determining the overall turns ration for the transformer.