ABSTRACT

A three-stage four–way 90–101 GHz power amplifier (PA) on 90 nm CMOS is reported. The PA consists of a meandrous four-way Wilkinson power divider, and common-source (CS) input and gain stages with inductive shunt-shunt feedback, followed by four-way CS output stage using a compact four-way current combiner. Wideband π-match inter-stage networks are used for broadband impedance and power matching. An LC input network (constituting a series capacitor, a parallel inductor, and an inductive shunt-shunt feedback) is used to convert the input impedance of the input-stage transistors to 50 Ω. This is the way to attain impedance matching at the outputs of the four-way Wilkinson power divider. Besides, an LC output network (constituting a series LC and a parallel inductor) is used to convert the 50 Ω load to the needed series RL load of the four-way current combiner. As a whole, the output-stage transistors operated at the maximal output power (P_out) and power-added efficiency (PAE). At 94 GHz, the PA attains gain of 20.1 dB, saturated P_out (P_sat) of 17.5 dBm, and maximal PAE (PAE_max) of 17.7%, one of the best results ever reported for W-band CMOS PAs. The remarkable performance of the CMOS PA reveals its potential for 94 GHz radar systems.

摘要

报道了一种在 90 nm CMOS 上的三级四路 90-101 GHz 功率放大器 (PA)。PA 包括一个曲折的四路 Wilkinson 功率分配器，以及具有感应并联-并联反馈的共源 (CS) 输入和增益级，然后是使用紧凑型四路电流组合器的四路 CS 输出级。宽带 π 匹配级间网络用于宽带阻抗和功率匹配。LC输入网络（由一个串联电容、一个并联电感和一个感性并联-并联反馈组成）用于将输入级晶体管的输入阻抗转换为50Ω。这是在四路 Wilkinson 功率分配器的输出端实现阻抗匹配的方法。除了，LC输出网络（由串联LC和并联电感组成）用于将50Ω负载转换为四路合流器所需的串联RL负载。作为一个整体，输出级晶体管在最大输出功率（P_out ) 和功率附加效率 (PAE)。在 94 GHz 时，PA 获得 20.1 dB 的增益，17.5 dBm 的饱和 P _out (P _sat ) 和 17.7% 的最大 PAE (PAE _max )，这是 W 波段 CMOS PA 有史以来最好的结果之一。CMOS PA 的卓越性能揭示了其在 94 GHz 雷达系统中的潜力。