US Patent 8717102 RF device with compensatory resonator matching topology

An amplifier circuit includes an RF transistor, a parallel resonator and a series resonator. The RF transistor has an input, an output and an intrinsic output capacitance. The parallel resonator is connected to the output of the RF transistor and includes a first inductive component connected in parallel with the intrinsic output capacitance of the RF transistor. The series resonator connects the output of the RF transistor to an output terminal and includes a second inductive component connected in series with a capacitive component. The series resonator is operable to compensate for a change in impedance of the parallel resonator over frequency.