A circuit includes a first power transistor stage internally configured to function as a voltage-controlled current source, a second power transistor stage having an input impedance which varies as a function of input power and an interstage matching network coupling an output of the first power transistor stage to an input of the second power transistor stage. The interstage matching network is configured to provide impedance inversion between the input of the second power transistor stage and the output of the first power transistor stage. The impedance inversion provided by the interstage matching network transforms the first power transistor stage from functioning as a voltage-controlled current source to functioning as a voltage-controlled voltage source at the input of the second power transistor stage.