一种低功耗高分辨率可编程增益放大器的设计

摘要

A low-power and high-resolution programmable gain amplifier is designed for Zero-IF receiver in this paper.Architecture of source degeneration resistor is adopted and the linearity is improved by using a gm-boosting circuit.The bandwidth of the amplifier is enlarged by adding compensation capacitors and the object of low-power design is achieved.The PGA is designed based on 0.25μm CMOS technology.Simulation results show that the PGA has a gain range from 0 to 62dB and the maximal consumption is 2.2mW at 2.5V supply voltage with a 0.5pF load.The gain resolution is 0.25dB.Its bandwidth is 10MHz and IIP3 is 17.9dBm.%该文设计了一种用于零中频接收机的低功耗高分辨率可编程增益放大器。该放大器采用源级电阻负反馈结构,利用跨导增强技术提高了放大器的线性度,并加入补偿电容扩展了带宽,实现了低功耗设计。该可编程增益放大器采用0.25μmCMOS工艺,仿真结果表明,在0.5pF负载电容的情况下,放大器增益动态的范围是0～62dB,2.5V供电电压下最大功耗为2.2mW,增益分辨率达到0.25dB,带宽10MHz,0dB增益时输入三阶交调点为17.9dBm。