高性能可变增益放大器（VGA）设计探讨

可变增益放大器（VGA）是模拟电路的一个基本组成模块。它们已经在移动通信系统,硬盘驱动系统等领域得到了广泛的应用。随着深亚微米CMOS工艺的到来,集成电路的特征尺寸越来越小,电源电压逐渐降低,高性能的VGA设计向模拟电路设计师提出了严峻的挑战。鉴于此,探讨了一些高性能VGA的设计技术,对开环VGA和闭环VGA两种结构作了详细的论述,并分析了相应的增益控制方法和优缺点。最后介绍了一种用于低压低功耗设计的高性能VGA增益级电路结构,并提出了VGA各种性能参数之间的折衷设计。

Design of High Performance VGA

Variable gain amplifiers（VGA） are basic building blocks employed in many analog electronic systems.They have applied widely in the systems such as mobile communications system,hard disk driver system and other fields.With the advent of deep sub-micro CMOS processing technology,implement of high performance VGA offers grave challenge for the analog designer due to the minimized feature size and reduced power supply voltage.In this paper,techniques for the design of high performance VGA are proposed and both open-loop and closed-loop configurations of VGA are elaborated.Finally,the tradeoff design between the performance parameters is suggested.