摘 要

Abstract II

1 绪论 1

1.1 课题研究的目的和意义 1

1.2 国内外研究现状 2

1.3 论文内容安排 3

2 APD老化测试系统的方案设计 4

2.1 雪崩光电二极管的特性参数 4

2.2 老化及寿命测试的理论依据 5

2.2.1 老化及加速寿命 5

2.2.2 阿伦尼斯(Arrhenius)模型 6

2.3 系统方案设计与分析 6

2.3.1 APD 参数测试系统整体方案概述 6

2.3.2 ADL5317设计方案 7

2.3.3 APD雪崩二极管的测试指标和测试难点 8

2.3.4 老化测试的方案 9

3 系统硬件电路的设计 10

3.1 ADL5317监控电路 10

3.2 升压电路 12

3.3 电流电压转换电路 13

3.4 OPA2188滤波电路 14

3.5 MCU电路 14

3.5.1 外部按键电路 15

3.5.2 配置的下载电路 16

3.6 液晶显示电路 17

4 系统电路的软件设计与电路调试 18

4.1 软件主程序的设计 18

4.1.1 DAC模块 19

4.1.2 AD采样模块 21

4.2 电路调试 22

4.2.1 VSET管脚电压调试 22

4.2.2 ADL5317电路的调试 24

4.2.3 微弱电流的检测 24

4.3 调试结果 24

5 总结与展望 25

5.1 总结 25

5.2 工作展望 25

参考文献 26

附录 27

致谢 28

摘要

光纤通信技术的迅猛发展使得人们对通信的质量和速度的要求也进一步提高，所以具有更快响应和更高灵敏度的光检测器件被人们所青睐。APD管具有灵敏度高、高光速的良好特性，它是一种凭借着强电场作用产生载流子倍增效应的高速光电二极管，在光纤通讯以及微弱信号的检测等领域中已经被普遍运用^[1]。

迄今为止，APD测试系统依然存在着测试方法复杂和价格昂贵等问题，这对于雪崩二极管的生产测试带来了严峻的挑战，为此本文设计了APD测试系统。另外，APD雪崩二极管在这个信息时代中备受青睐，在光电传输系统中被普遍应用，所以一旦其失效将造成巨大损失，这使得人们对APD管的可靠性产生了顾虑，从而人们开始对APD管进行老化测试的研究。

尽管这些年我国在光纤通信领域处于快速发展的阶段，由于我国起步较晚，我国在该领域与一些发达国家还是存在一定差距，许多测试仪器仍然从国外进口， 价格比较昂贵。国内也研发了APD雪崩光电二极管的测试仪器与设备，但是国内这方面的研究大部分都是针对科研的需要，并没有解决公司生产测试复杂、价格昂贵的问题为此，对APD老化测试系统的研究具有重要意义。

本文从研究雪崩二极管的特性参数入手，确定了需要测量的两个个参数：击穿电压和暗电流。根据本课题需要测量的参数制定了APD雪崩二极管参数测试电路以及老化测试方案。APD雪崩二极管参数测试电路的关键任务是能够输出可调节的高电压并且可以检测微弱的电流，为此本文最终使用了ADL5317设计方案。基于ADL5317芯片的参数测试电路主要包括了ADL5317模块、升压电路、电流电压转换模块和MCU控制模块等。单片机选用了美国微芯科技公司的DSPIC33FJ64GP804芯片，利用该单片机内部的DA和AD单元来对电压电流进行采集和控制，通过PIC单片机编写软件对AD模块采集的数据进行处理，将最后的测量结果显示在液晶屏上。

本文实现了APD雪崩光电二极管的击穿电压、暗电流和倍增因子的测量，并且具有成本低、性能稳定、干扰小的特点。另外，本文虽未实现最后的老化测试，但是给出了老化测试的理论依据和方案，基本完成毕业设计的要求。

关键词： 微弱电流检测、雪崩二极管、升压电路、电流电压转换

Abstract

The rapid development of optical fiber communication technology makes people's communication quality and speed requirements are further improved, so with faster response and higher sensitivity of the photodetection devices are favored. APD avalanche diode with high sensitivity, high light speed of good characteristics, it is a strong electric field with the role of carrier multiplier effect of high-speed optoelectronic devices in the optical fiber communication, weak signal detection and other fields have been widely used.

So far, APD test system still exists the test method is complex and expensive and so on, which for avalanche diode production test has brought serious challenges, for which this article designed the APD test system. In addition, APD avalanche diode in this information age favored in the photoelectric transmission system is widely used, so once its failure will cause huge losses, which makes the reliability of APD pipe concerns, so people began to APD Tube for aging test.

Although China in the field of optical fiber communications in the field of rapid development, due to the late start in China, China in the field and some developed countries there is still a gap, many test equipment is still imported from abroad, the price is more expensive. China has also developed a APD avalanche photodiode test equipment and equipment, but most of the domestic research in this area are for the needs of scientific research, and did not solve the company's production test complex and expensive issues for this, the APD aging test system Research is of great significance.

In this paper, we study the characteristics of the avalanche diode to determine the two parameters need to be measured: breakdown voltage and dark current. The APD parameter test circuit and the aging test protocol were developed according to the parameters to be measured. APD parameter test circuit is the key task to be able to output adjustable high voltage and detect weak current, for this end the use of the ADL5317 design. Based on ADL5317 chip parameter test circuit mainly includes ADL5317 circuit module, boost circuit module, current and voltage conversion module and MCU control module. Single-chip selection of the US Microchip Technology DSPIC33FJ64GP804 chip, the use of the microcontroller's internal DA and AD units to collect and control the voltage and current, the preparation of the software to collect the data processing, the final measurement results displayed on the LCD screen The