摘要
可变增益放大器是模拟单元电路之一,起着变化增益、调整信号动态范围、稳定信号功率的作用。文章综述了CMOS集成可变增益放大器的研究情况;给出了可变增益放大器的定义、应用、分类和主要指标,描述了多种开环和闭环放大器的结构,分析了相应的增益控制方法及其优缺点;说明了在CMOS工艺下实现放大器增益按指数变化的几种途径。最后,介绍了用于无线数字通信,具有宽带、高线性、低电源电压等高性能可变增益放大器的设计实例。
Variable gain amplifier （VGA） is an analog circuit, which varies gain, adjusts signal dynamic range and stabilizes signal power. An overview of CMOS integrated variable gain amplifiers is made. The definition of VGA and its function, classification and specifications are elaborated. Different open- and closed-loop VGA＇s are described, and the advantages and disadvantages of gain control strategies are analyzed. Approaches to achieving exponential gain in CMOS technology are explained. Finally, examples of high performance VGA＇s used in wireless digital communication are introduced, which mainly focus on broad bandwidth, high linearity and low supply power.
出处
《微电子学》
CAS
CSCD
北大核心
2005年第6期612-617,共6页
Microelectronics
基金
国家重点基础研究发展规划资助项目(G2000036508)
国家自然科学基金资助项目(编号90407006)
关键词
放大器
可变增益放大器
可编程增益放大器
指数增益控制
Amplifier
Variable gain amplifier
Programmable gain amplifier （PGA）
Exponential gain control
