Over 70% PAE packaged GaN HEMT through wideband internal matching at second harmonic in S-band

Reported is a design methodology to efficiently control source and load impedances of a power GaN HEMT at the second-harmonic frequency inside a metal ceramic package. Second-harmonic source control is more precisely investigated. A specific filter is implemented at the gate side within the package to transform external source impedances into negative reactances seen by the internal device at second-harmonic frequencies. Whatever the external source termination presented at second-harmonic frequencies, source impedances seen by the internal die are confined to high efficiency regions. This methodology is applied to a 20 W packaged GaN HEMT using internal control of input and output second-harmonic impedances to reach more than 70 of power-added-efficiency (PAE) on 30 relative bandwidth in S-band.