高线性光耦合型隔离放大器的研制

An opitically—isolated amplifier with linearity improvement

本文提出一种提高光耦合型隔离放大器线性度的新方法,它采用直流偏置、电流反馈及差分技术有效地补偿了光耦合器件的非线性误差。文中详细介绍了电路的基本原理,并给出了实验结果,它表明:在不需任何特殊元件和制作工艺条件下,放大器的非线性误差小于0.1％FS,最高工作频率大于300kHz。

This paper proposes a new method to improve the linearity of anopticallycoupled isolation amplifier. This method adopts the technologies of current biasing, current feedback and differentiation so as to compensate the non-linearity error of the isolation amplifier. The paper also introduces in detail the basic operating principle of the circuits. In addition, it gives the experimental result,which shows the isolation amplifier with non-linearity error of less than 0.1%FS and the highest working frequency of greater than 300kHz can be easily achieved without specia components and technologies.