High efficiency GaN current‐mode class‐D amplifier at 2.6 GHz using pure differential transmission line filters.

In class‐D operation the impedances of the output network at each harmonic frequency at the intrinsic terminals of the transistors are of main importance. This reported work demonstrates a new concept using pure differential transmission line filters for the matching of these impedances. Furthermore, de‐embedding techniques are used to compensate the impedance transforming characteristics of the package parasitics. A current‐mode class‐D (CMCD) amplifier with a power‐added efficiency (PAE) of 62% and a corresponding output power of 29.5 W at 2.6 GHz has been demonstrated. To the authors' knowledge, these are the highest reported values of the PAE as well as the output power at this frequency for a CMCD. [ABSTRACT FROM AUTHOR]