A high linearity Doherty power amplifier integrated with output matching
circuitry comprised of capacitive elements, inductive elements, and/or
shunted transmission lines. In one embodiment, the output matching
circuitry is implemented by transmission lines periodically shunted via
capacitors, where some or all of the shunted transmission lines have
lengths less than a quarter of a wavelength of a power amplifier input
signal. In another embodiment, the output matching circuitry is
configured with lumped inductive and capacitive elements. In addition, to
improve efficiency and linearity characteristics, the power amplifier
receives a voltage control signal to bias a supplemental amplifier so
that the power amplifier operates in a Doherty mode in a low output power
range and in a non-Doherty mode in a high output power range.