雪崩光电二极管数控偏压源的设计

为保证雪崩光电二极管(APD)在温度变化的情况下始终处于最佳工作状态,人们研究了多种偏压控制方案。针对传统的偏压控制存在的缺陷,文章从APD的倍增机理出发,分析了温度对雪崩增益的影响,得到偏压与温度的特性曲线。基于偏压的虚警控制原理,利用单片机便于数据处理和存储的特点,设计了一个自动跟踪雪崩管击穿电压的数控偏压电路。该电路能在温度大幅度变化的情况下保证APD正常工作,适合于高频连续信号检测的光电系统。

Design of Digital Circuit for Bias Voltage of Avalanche Photodiode

In order to ensure the APD's optimum operating in conditions of different temperature,many bias voltage control schemes have been designed.Against the disadvantage of the conventional bias voltage control schemes and based on the multiplication mechanics,this paper analyzed the temperature how to have an effect on the avalanche gain,obtained the curves between bias voltage and temperature characteristic.Based on the false alarm control theory and the characteristic of the chip microcomputer's convenience to treating and holding digital information,a numeric control bias circuit auto-tracing the avalanche breakdown voltage is designed.This circuit can guarantee the normal work of APD in large variation of temperature,it is very suited to the photoelectric system for the high-frequency and continuous signal detection.