说明：  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 circuit of the analog unit, a change is the gain, adjust the signal dynamic range, stability and the role of signal power. This paper reviews the CMOS integrated variable gain amplifier of the situation given the definition of a variable gain amplifier, application, classification and key indicators, describes a variety of open and closed loop amplifier structure, analysis methods and the corresponding gain control The advantages and disadvantages illustrates the CMOS process to achieve changes in amplifier gain in several ways according to index. Finally, introduced for wireless digital communications, with broadband high linearity and low supply voltage high-performance variable-gain amplifier design examples.)