一种新颖的CMOS电流控制型可变增益放大器

A New Kind of CMOS Current-Mode Variable-gain Amplifier

采用0.35μm CMOS技术实现了一种增益按指数规律变化的电流控制型可变增益放大器(VGA)。通过采用Pseudo-exponential函数逼近方法设计指数发生电路,在1.5 V电压下工作所消耗的功率不超过1 mW。仿真结果表明,在输入控制电流误差为0.5 db的范围内,该VGA的增益控制范围可以达到30 db,适用于各种模拟信号处理电路。

A CMOS exponential-control variable-gain Amplifiers （VGA） base on a 0. 35 CMOS process is presented in this paper. A pseudo-exponential function is used in the design of exponential circuit,the power dissipations is not to surpass 1 mW with the supply voltage 1.5 V. The simulation result indicated,for the case of the input control current error within 0.5 db,the gain control range of the proposed VGA can be 30 db, which is useful in analogue signal prosessing applications.