摘要
光电探测器前置放大电路设计的好坏会直接影响整个检测系统的信噪比。为了提高对微弱光信号的检测精度,使用低噪声光电二极管和运算放大器,并选择光电二极管工作在光伏模式,设计出了光电探测器的低噪声前置放大电路。通过采用超前校正方法对由光电二极管结电容及运算放大器输入电容引起的相移进行补偿,克服了光电二极管寄生参数引起的转换电路的不稳定性。给出了在设计低噪声光电检测电路时对光电器件及前置放大器等元器件的相关参数进行选择的依据。
The preamplifier circuit in a photoelectric detector can directly affect the signal-to-noise ratio（SNR） of a whole detection system.To improve the detection precision of weak photocurrent, a low noise preamplifier circuit for a photoelectric detector based on a photodiode（in photovoltaic mode） and an operational amplifier is designed.The instability in an I/V conversion circuit due to the parasitic parameters of the photodiode is overcome by using a lead correction method to compensate the phase shift caused by the junction capacitance of the photodiode and the input capacitance of the operational amplifier.Finally,the reasons for choosing the relevant parameters of the components such as photoelectric devices and preamplifiers in the design of this low noise photoelectric detection circuit are given.
出处
《红外》
CAS
2011年第3期14-18,共5页
Infrared
