A 1-V, 800-MHz CMOS class-E power amplifier with power control for wireless sensor network

This paper presents a 1-V class-E power amplifier for Wireless Sensor Network in a 0.18-μm CMOS process. The design exploits a cross-coupled structure to achieve high operating frequency and reduce the size of the transistors. Pairs of digital MOS switches manipulate the cross-coupled structure to work or not. To control the output power, a topology of three parallel units with different output power is adopted. An off-chip balun is also proposed for output differential-to-single ended conversion and impedance matching. At 800 MHz, the power amplifier can deliver a range of output power from -5.5 to 6.6 dBm and achieve maximal power-added efficiency (PAE) of 52.7% at 6.6 dBm.