一种915 MHz 0.18 μm CMOS增益可变的功率放大器

A 915 MHz 0.18μm CMOS Variable Gain Power Amplifier

针对射频前端发射距离的不确定性,设计了一款基于0.18μm CMOS工艺的增益可变功率放大器。该功率放大器的中心工作频率为915 MHz,工作在AB类,采用两级单端共源共栅结构。输入级采用类似开关功能的栅压,控制3个并联的共源共栅结构输出管的导通,得到增益和输出功率可变的功率放大器。仿真结果表明,在输入级1.8V和输出级3.3V的电源电压下,该功率放大器功率增益范围为9~25.8dB,1dB压缩点处的最大输出功率为21.47dBm,最大功率附加效率为29.6%。该放大器的版图面积为（1.4×1.2）mm2。

A variable gain power amplifier was presented for the uncertainty of RF front-end transmit distance, which was based on 0. 18 μm CMOS process. The working center frequency of the power amplifier was 915 MHz, which worked in class AB and used two stage single-ended cascode structure. To obtain variable gain and output power for the power amplifier, the structure of input stage used gate voltage to control the 3 parallel cascode output tube conduction, which was similar to the function of the switch. The layout simulation results showed that the power amplifier achieved a power gain range of 9 to 25.8 dB, the maximum output power was 21.47 dBm at 1 dB compression point, and the maximum power added efficiency was 29.6%. The layout size was （1.4× 1.2） mm2.