A 2.14GHz watt-level power amplifier with passive load modulation in a SOI CMOS technology

This paper presents the implementation and measurement results of a power amplifier with passive load modulation targeting Femtocell base station applications and integrated in SOI CMOS 130nm process. The proposed structure combines a SOI LDMOS power stage with a SOI CMOS Tunable Matching Network (TMN) based on high voltage switched capacitors in order to improve PA efficiency at back-off power. At 2.14GHz, the PA achieves 31.5dBm of measured peak power under 4V supply and compared to a conventional PA with fixed output matching network, the measured efficiency improvement is 60 % at 8.5 dB back-off.