E-PHEMT for single supply, no drain switch, and high efficiency cellular telephone power amplifiers

Abstract

Performance of a newly developed enhancement mode power PHEMT technology is demonstrated for single supply, no drain switch, high efficiency cellular telephone power amplifier applications. The E-PHEMT features Idss=0.5 pMmm, Imax=190 mA/mm, Vp=+0.3 V, Gm=340 mS/mm, and Vbdg=20 V. When matched onwafer for a compromise between power and efficiency at 900 MHz, the EPHEMT achieves Pout=100-140 mW/mm with associated PAE-70 YO at 3.2 V and Pout=35 mW/mm and PAE=71% at 1.5 V. The new E-PHEMT has high gain, excellent efficiency under linear and 1dB compressed gain conditions, making it attractive for high efficiency linear power amplifiers. A 10 mm E-PHEMT achieves remarkably similar saturated power and efficiency performance over 0 to 400 mA quiescent bias current range, which allows low power dissipation operation for high reliability.

A wideband high dynamic range triple‐stacked FET dual‐shunt distributed analogue voltage controlled attenuator

“…To verify the proposed design technique, a triple‐stacked distributed VCA has been fabricated in a 0.15‐μm enhancement mode (E‐mode) GaAs process [19]. Compared to conventional depletion mode GaAs processes, the E‐mode process offers the capability of using a single positive control voltage [20–22]. All the transistors are identical and have a gate width of 2 25 µm.…”