基于MOS场效应晶体管的高精度可变电阻器  

HIGH PRECISION VARIABLE RESISTOR BASED ON MOSFET

作　　者：霍显杰 田力学 李永刚 李颖弢[1] HUO Xianjie;TIAN Lixue;LI Yonggang;LI Yingtao(School of Physical Science and Technology,Lanzhou University,Lanzhou,Gansu 730000)

机构地区：[1]兰州大学物理科学与技术学院,甘肃兰州730000

出　　处：《物理与工程》2021年第6期50-56,62,共8页Physics and Engineering

基　　金：甘肃省科技计划项目(20JR5RA307);甘肃省委组织部甘肃省重点人才项目。

摘　　要：本文介绍了一种有源可变电阻器的实现方法,该电阻器使用MOS场效应晶体管作为开关器件,通过控制MOS场效应晶体管是否导通来控制与之并联的电阻是否接入电路,电阻逐个使用2^(n)Ω。基于电阻分压定律,微控制器(MCU)控制电压控制的电压源(VCVS)的电压来等效模拟电阻分压以达到模拟电阻的目的,本设计引入了比例积分PI控制,很好地消除了误差电阻的影响,提高了电阻精度,且具有良好的抗干扰性能和温度补偿性能。相较已有的一些变阻器,该变阻器具有体积小、精度高、易集成和电阻连续可控等优点,可以广泛应用于电路设计、通信工程、控制工程等领域,在大学物理实验中亦有广泛的用途。This paper introduces a method to realize an active variable resistor.The resistor uses MOSFET as the switching device,and controls whether the parallel resistance is connected to the circuit by controlling the MOSFET.The resistor uses 2^(n)Ω one by one.Based on the law of resistance partial voltage,Microcontroller Unit(MCU)controls the voltage of voltage controlled voltage source(VCVS)to equivalent analog resistance to achieve the purpose of analog resistance.In this design,proportional integral PI control is introduced to eliminate the influence of error resistance,improve the precision of resistance,and thus good anti-interference performance and temperature compensation performance can be obtained.Compared with some existing variable resistor,the variable resistor has the advantages of small size,high precision,easy integration and continuous controllable resistance.It can be widely used in circuit design,communication engineering,control engineering and other fields,and also can be widely used in college physical experiments.

关 键 词：MOS场效应晶体管 可变电阻 比例积分控制(PI控制) 微控制器(MCU) 电压控制的电压源(VCVS) 

分 类 号：TM546[电气工程—电器]