Abstract: A Doherty amplifier system (10) is disclosed having a carrier amplifier (12) with a carrier drain bias input (14), and a peak amplifier (24) having a peak drain bias input (26), and a peak gate bias input (28). Also included is a programmable bias controller (40) having a data interface configured to receive peak-to-average power ratio (PAPR) data associated with a basestation. The programmable bias controller (40) further includes a processor (46) coupled to the data interface and configured, in response to the PAPR data, to determine and apply bias levels to the carrier drain bias input (14), the peak drain bias input (26), and the peak gate bias input (28) to provide an amplifier efficiency between 30% and 78.5%.

Abstract: A power amplifier with a quasi-static drain voltage adjustment is provided that has a transistor that is made from Gallium Nitride (GaN). In an exemplary aspect, the transistor is a field-effect transistor (FET) having a source, gate, and drain. The transistor is tested for process variations. Based on detected process variations, a microcontroller may raise a drain voltage to increase output power capability.