摘要
为满足半导体探测器输出电流检测系统的需求,设计了与之相适应的前置放大器。该前置放大器基于超低偏置电流运放ADA4530,采用单个反馈电阻和T型反馈网络的I/V变换前置放大电路组成。测试结果表明:该前置放大器的放大倍数可达10 mV/pA,直流偏移为8μV;对于pA级分辨率,其输出噪声电压频谱密度仅为17.75 nV/(Hz)~(1/2),输出总噪声为409μV;可用于μA~pA范围内的核辐射探测器电流信号测量。
In order to meet the needs of the semiconductor detector output current measurement system,designed with the corresponding preamplifier. The preamplifier is based on the ultra-low bias current op ampADA4530,using a single feedback resistor and a T-feedback network of I/V conversion preamplifier circuits. The results show that the preamplifier has a gain of 10 mV/pA and a DC offset of 8 μV. For the pA resolution,the output noise voltage density is only 17. 75 nV/( Hz)~(1/2),and the total noise is 409 μV. It can be used for the range of μA ~ pA current signal measurement of nuclear radiation detector.
引文
[1]刘国福,杨俊,王艳玲.空间粒子辐射探测技术基础[M].长沙:国防科技大学出版社,2016:79-82.
[2]远坂俊昭.测量电子电路设计:模拟篇[M].彭军,译.北京:科学出版社,2006:39-41.
[3]ADA4530 Data Sheet[OL].http://www.analog.com/ada4530-1?doc=ada4530-1.pdf.
[4]Walt Jung.运算放大器应用技术手册[M].张乐峰,译.北京:人民邮电出版社,2009:191-193.
[5]王晶,李斌康,阮林波,等.微弱电流高精度自动测量系统[J].强激光与粒子束,2012,24(8):1975-1979.
[6]魏立乾,雷升杰,方美华.辐射监测的微弱电流测量I/V转换技术[J].仪器仪表与分析监测,2010,26(3):28-31.