碲镉汞红外探测器前置放大电路低温稳定性研究

A Study on the Low-Temperature Stability of Preamplifier Circuits for HgCdTe Infrared Detectors

摘要:

在航天工程应用中发现，室温下HgCdTe红外探测器前置放大电路输出正常，但是温度降低到-55℃时，输出有振荡现象，对探测器施加红外辐照，振荡现象加剧。本文首次对该现象进行系统研究，提出了HgCdTe红外探测器电路在低温下光照后的等效电路模型，从相位裕度与增益裕度角度分析前置放大电路在低温下产生振荡的机理，并在此基础上，提出了抑制低温光照后前置放大电路振荡的解决方法，实验结果验证了该方法的有效性。

Abstract:

In aerospace applications, it is found that the output of HgCdTe infrared detector preamplifier circuit is normal at room temperature, but there is an oscillation phenomenon when the temperature is reduced to -55℃, and the oscillation phenomenon is aggravated by applying infrared irradiation to the detector. In this paper, this phenomenon is systematically investigated for the first time, and an equivalent circuit model of the HgCdTe infrared detector circuit after low-temperature irradiation is presented. The mechanism of the oscillation of the preamplifier circuit at low temperature is analysed from the perspective of phase margin and gain margin. Based on this analysis, a solution is proposed to inhibit the oscillation of the preamplifier circuit after illumination at low temperatures. The validity of the method was confirmed by the experimental results.