A 1.92mW Filtering Transimpedance Amplifier for RF Current Passive Mixers

📋 论文概要

该论文提出了一种用于射频电流无源混频器的滤波跨阻放大器（TIA），功耗仅为1.92mW。通过优化电路结构，在保持低输入阻抗的同时实现了滤波功能，有效降低了混频器输出端的电压摆幅，改善了接收机的噪声和线性度性能。

💡 主要创新点

• 提出了一种低功耗滤波TIA架构，在传统TIA基础上集成滤波功能，无需额外有源滤波器。
• 通过电流反馈和电容分流技术，在低功耗下实现了宽带宽和低输入阻抗，适用于无源混频器后级。

🏷 关键词

📄 原文摘要

Nowadays, current passive mixers represent the state of the art for signal downconversion in wireless receivers. In such kind of structures, noise, distortions and losses are strictly correlated to the performance of the stage following the mixer. The most common solution adopted to sense the down-converted current is a transimpedance amplifier (TIA) in shunt with a capacitance to ground that assures a low input impedance when the loop gain of the amplifier decreases (Fig. 20.9.1a). A low input impedance is necessary to have a small voltage swing at the output of the mixer (typically few hundreds mV) to minimize the modulation of the switch resistance and with it the distortion produced during the downconversion. The input capacitance can also be used to filter the majority of the out-of-band interferers by transforming the TIA into a filter [1,2] (Fig. 20.9.1b). This reduces the dynamic range required by the TIA and its power consumption.

👥 作者与机构

Tian Ya Liu, Antonio Liscidini

University of Toronto, Toronto, ON, Canada