低噪声微弱近红外光检测电路设计  

Design of low-noise and weak near-infrared light detection circuit

作　　者：夏建华 谢小鹏[1] 高国刚 肖郡龙 Xia Jianhua;Xie Xiaopeng;Gao Guogang;Xiao Junlong(School of Mechanical&Automobile Engineering,South China University of Technology,Guangzhou Guangdong,510640;Dongguan Baoteng Machinery Co,Ltd.,Dongguan Guangdong,523839)

机构地区：[1]华南理工大学机械与汽车工程学院,广东广州510640 [2]宝腾智能润滑技术(东莞)有限公司,广东东莞523839

出　　处：《电子测试》2022年第11期5-10,共6页Electronic Test

摘　　要：随着半导体行业的快速发展,红外检测技术凭借其非侵入式、高速、实时检测、体积小、结构简单的优势得到重视,在气体浓度检测、流体检测等领域得到广泛应用。本文设计了宽带宽、低信噪比的微弱红外光信号检测电路,通过分析跨阻放大电路的各个噪声来源,得出其等效噪声模型和噪声密度曲线,随后设计低通滤波器以在满足目标带宽的同时减少电路输出噪声。最后通过Ltspice仿真对滤波前后电路的噪声密度曲线和总噪声曲线进行对比,。结果表明,本文设计的检测电路能有效对高频噪声进行滤波,其总输出信号噪声降低68.71%,信噪比达到84.86d B。同时其制成的电路板体积较小,易于集成到传感器中作为信号检测电路。With the rapid development of the semiconductor industry,infrared detection technology has gained attention with its advantages of non-invasive,high-speed,real-time detection,small size,and simple structure,and has been widely used in gas concentration detection,fluid detection and other fields.This paper designs a weak infrared light signal detection circuit with wide bandwidth and low signal-to-noise ratio.By analyzing the various noise sources of the transimpedance amplifier circuit,the equivalent noise model and noise density curve are obtained,and then a low-pass filter is designed to satisfy Reduce the output noise of the circuit while reducing the target bandwidth.Finally,through Ltspice simulation,the noise density curve of the circuit before and after filtering is compared with the total noise curve.The results show that the detection circuit designed in this paper can effectively filter high-frequency noise,the total output signal noise is reduced by 68.71%,and the signal-tonoise ratio reaches 84.86dB.At the same time,the circuit board made of it is small in size and easy to integrate into the sensor as a signal detection circuit.

关 键 词：IV转换 低噪声 红外检测 

分 类 号：TM93[电气工程—电力电子与电力传动]