High-efficiency class E MMIC power amplifiers at 4.0 GHz using AlGaN/GaN HEMT technology

Two high-efficiency Class E MMIC power amplifiers designed at 4 GHz using AlGaN/GaN HEMT technology are presented. The first circuit was designed using a 0.5 mm (4 × 125 um) HEMT and when biased at 25 V drain bias it produced 61 % PAE, 33.8 dBm of output power and maximum gain of 14.8 dB. The second circuit used a 1 mm (8 × 125 um) HEMT and at 30 V drain bias it produced 57% PAE, 36 dBm of output power, and maximum gain of 13 dB. The key to obtaining the high gain, PAE and output power produced by these circuits is accurate modeling of the HEMTs and the passive components.