Class-F amplifier loading networks: a unified design approach

A method is shown which greatly simplifies the design of third-order loading networks for Class-F switching amplifiers. The goal of the method is to determine the approximate component values for interstage and final amplifier loading networks that present the proper load conditions at the primary frequency f/sub 0/ and it´s third harmonic 3f/sub 0/, while at the same time introducing a low impedance to ground at the second harmonic frequency 2f/sub 0/. Design procedures and equations are presented for one class of final amplifier and three classes of interstage loading networks.