在多元光导探测器的工程应用中，串音是影响系统性能的一个重要因素。其中，由公共地线电阻引入的电子学串音 可以通过提高偏置电阻来抑制。本文从HgCdTe光导探测器的工作特性出发，设计了等效内阻很高的恒流偏置低噪声前置放大电路。对电 路的工作原理和噪声性能进行了分析和讨论，给出了电路的噪声模型，导出了电路的等效输入噪声表达式，并进行了电路实现和低噪声 性能测试。

The crosstalk in a multi-element photoconductor is one of the factors which have influences on the performance of a system. The electronic crosstalk caused by ground resistance can be reduced by increasing bias resistance. According to the characteristics of a HgCdTe photoconductive detector, a preamplifier with a constant current bias circuit is designed. The operation principle and noise of the circuit are analyzed. The noise model of the circuit is given. An expression for its equivalent input noise is derived. Finally, the circuit is implemented and its noise performance is tested.