Abstract
In the transition of industrial production from mechanization to intelligent automation, the burn-in screen machine that undertakes the task of screening electronic components has been widely used. However, due to the needs of element screening technology, the power supply and power supply lines of burn-in screen machine need to work in a closed environment with high temperature difference and strong magnetic field for a long time, the actual stress exerted on the electronic components may deviate greatly from the set value or even completely fail. Therefore, in order to examine the actual ability of the burn-in screen machine to undertake the screening task, the on-line detection of the voltage and current output by the burn-in screen machine is required. Because the temperature inside the burn-in screen room constantly changes between -55°C and 80°C and there are some strong electromagnetic interference signals, and the voltage detection accuracy can reach 0.05%, the current detection accuracy can reach 0.07%, and the general measurement and test system is difficult. To meet the requirements, it is necessary to develop and design a special inspection system. The main research contents of this article are as follows:
Firstly, aiming at the high precision requirement of on-line detection system, this topic researches systematic error theory in advance, determines the error distribution principle and error synthesis method of the system, and guides the design of the overall system and hardware circuit of the system. At the same time, the thermal design and electromagnetic shielding technology of electronic equipment were studied. Based on the characteristics of the internal environment of burn-in screen room, the system was designed to resist temperature and electromagnetic interference. Based on the above research results and system requirements, the overall design of the system was completed.
Secondly, the overall hardware structure of the online detection system is designed. The hardware circuit is divided into five modules: analog signal conditioning unit, isolation unit, data acquisition unit, STM32 minimum system and communication unit. The design ideas, circuit structure of each module and the choice of devices are discussed in detail, and calculate the theoretical errors caused by various components in the analog signal conditioning unit, which is the main source of systematic errors, so as to provide the necessary guarantee for systematic errors meeting the technical requirements.
Then, t he μCOS-II real-time operating system is transplanted in the microcontroller, and designs independent user functions on this operating system to divide the system
time, based on LabWindows/CVI developed and designed the system's PC software, to achieve the system's automatic testing functions and online detection functions.
Finally, the data acquisition function, temperature control function and communication function of the system are verified, and a system test platform is set up to complete the overall function debugging of the system and the calibration of the measurement data. The system error is measured and the performance of the system is evaluated in the field environment where the burn-in screen machine is operated. The experimental results show that the on-line detection system designed in this paper can complete the on-line detection task of the electronic components burn-in screen machine under the environment of high temperature difference and strong magnetic field in the burn-in working room, and the performance indicators meet the technical requirements.
Keywords: on-line detection, burn-in screen, anti-jamming design, error analysis
目录
摘要 ............................................................................................................................... I Abstract ............................................................................................................................. I I 第1章绪论 . (1)
1.1 课题背景及研究的目的和意义 (1)
1.2 检测技术的研究现状和未来发展 (2)
1.2.1 检测技术的国内外研究现状 (2)
1.2.2 检测技术的发展分析 (4)
1.3 本文的主要研究内容 (6)
第2章系统误差分析及抗干扰技术研究 (7)
2.1 系统需求分析 (7)
2.1.1 老化筛选设备状况分析 (7)
2.1.2 系统的基本要求和技术指标 (8)
2.2 系统误差分析理论研究 (9)
2.2.1 系统的误差分配 (9)
2.2.2 系统的误差合成 (10)
2.3 系统抗干扰技术研究 (11)
2.3.1 抗温度干扰技术 (12)
2.3.2 抗电磁干扰技术 (13)
2.4 系统总体方案设计 (16)
2.5 本章小结 (16)
第3章在线检测系统的硬件电路设计 (18)
3.1 总体电路结构设计 (18)
3.2 电压调理单元电路设计 (18)
3.2.1 电压测量电路设计 (19)
3.2.2 档位切换电路设计 (20)
3.2.3 器件的选取及误差计算 (21)
3.3 电流调理单元电路设计 (22)
3.3.1 电流取样电路设计 (22)
3.3.2 器件的选取及误差分析 (23)
3.4 隔离单元电路设计 (25)
3.5 数据采集单元电路设计 (26)
3.5.1 通道切换电路设计 (26)
3.5.2 AD转换电路设计 (28)
3.6 最小系统电路设计 (29)
3.6.1微控制器的选择 (29)
3.6.2 最小系统电路设计 (30)
3.7 通信单元电路设计 (33)
3.7.1 USB转串口电路设计 (33)
3.7.2 红外通信电路设计 (33)
3.7.3 SD储存电路设计 (34)
3.8 本章小结 (34)
第4章在线检测系统软件开发 (35)
4.1 基于μCOS-II的在线检测系统软件框架 (35)
4.2 μCOS-II实时操作系统 (36)
4.2.1 μC/OS实时操作系统的移植 (36)
4.2.2 在线检测系统的任务设计 (37)
4.3 操作系统任务程序设计 (38)
4.3.1 数据采集程序设计 (38)
4.3.2 实时时钟程序设计 (40)
4.3.3 红外通信程序设计 (41)
4.3.4 SD卡存储程序设计 (41)
4.4 在线检测系统的上位机软件开发 (45)
4.4.1 上位机软件功能 (45)
4.4.2 自动测试模块设计 (46)
4.4.3 在线检测模块设计 (48)
4.5 本章小结 (49)
第5章在线检测系统功能验证与性能评估 (50)
5.1 系统功能测试 (50)
5.1.1 系统模块功能测试 (50)
5.1.2 测试平台搭建与验证 (53)
5.2 现场环境下系统性能评估 (54)
5.2.1 系统检测数据的校准 (55)
5.2.2 系统误差测量 (59)
5.3 在线检测系统的实际应用 (60)
5.3.1 系统在线检测应用方案 (60)
5.3.2 在线检测内容展示 (61)
5.4 本章小结 (62)
结论 (63)
参考文献 (64)
攻读硕士学位期间发表的论文及其它成果 (68)
哈尔滨工业大学学位论文原创性声明和使用权限 (69)
致谢 (70)