一种具有极低THD值的差分运放的设计

Analyzing and Designing of a Differential Amplifier with Low THD Value

为了减小运算放大器由于自身及外界原因存在失调导致输出波形的THD值较大的状况,文中首先介绍了全差分运算放大器的基本架构,并在此基础上采用一种新颖的选通输入方式及简单的共模反馈电路设计了一款高增益,低THD值的全差分运放.经计算且在TSMC0.6μmBCD工艺上,用Cadence、Hspice等EDA软件对设计电路进行仿真,各项指标均符合设计要求,输出波形的THD值仅为0.385%.目前该电路已成功应用在一款D类音频功率放大芯片中.

In order to reduce the THD value caused by the amplifier and the environment,based on the principle of the fully differential amplifier,by utilizing a new kind of methods on the input stage and a kind of simple CMFB circuit,a novel high gain and low THD value amplifier is designed.According to the calculation and simulation using Cadence、Hspice and etc,the results are satisfied all the requirements that we have designed and the THD of the output waveform is only 0.385%.Now this new circuit has applied in a ...