基于焊点形态理论的SMT焊点质量模糊故障诊断技术研究

根据SMT焊点质量与焊点的三维几何形态直接相关的特点，提出了SMT焊点形态理论。以该理论为支持，提出了SMT焊点质量模糊诊断技术。将实际焊点几何形态与合理焊点几何形态对应比较，作为模糊输入向量，以焊点的故障缺陷发生可能度作为模糊输出向量。通过可信度约束的模糊规则与正反向模糊推理，进行焊点质量模糊故障诊断。以四边扁平封装器件(QFP)为例，进行了实例验证。     

SMT-TAB: A process planning system for PCB assembly using TAB and SMT

Process planning is a critical function in any manufacturing domain. This is especially true in the electronics manufacturing area where substantial heuristic and experiential knowledge is commonly used during process plan development. While research in computer-aided process planning (CAPP) has tended to concentrate in the machining realm, few CAPP systems have been developed for electronics manufacturing applications and more specifically for the printed circuit board (PCB) assembly domain. Besides, the CAPP systems that have been developed for this area have dealt with either insertion mount or surface mount PCB assembly processes only.Tape automated bonding (TAB), though a relatively new technology, is gaining importance in electronics assembly owing to its inherent advantages. The advent of fine pitch technology together with the ever increasing need for more inputs/outputs and greater pin counts in integrated circuit applications has enhanced the use of TAB technology in electronics manufacturing. This trend has been further augmented by the increasing need for compactness in consumer electronics.This research designed and developed a prototype CAPP system for the PCB assembly domain. The system developed generates a process plan for PCBs populated with surface mount and/or TAB components. An artificial-intelligence based expert system approach has been used in the design and development of the CAPP system. Outputs generated by the system are presented along with ideas for future research.     

Locating and checking of BGA pins’ position using gray level

A machine vision system for SMT-mounting machine applications usually involves a two-stage algorithm. It first measures the centroid and rotation angle of the SMD, and then checks each pin’s area, position error, and grid coordinate. In this paper a set of complete procedures is proposed to locate and check the BGA image. During the locating procedures, one first calculates a threshold for the frame using an iterative threshold algorithm. If an object is found under this threshold, then the pin area is calculated by a local threshold. After that, whether this object is a pin or not is decided by its neighbouring pins’ relative positions, then the approximate rotation angle for finding the outer pins is calculated, and the centroid as well as the rotation angle of a BGA component is calculated by the rectangular least-squares algorithm. The checking procedure also measures each pin’s area using the moment algorithm, it then calculates the radius of the moving sum using each pin’s area, and finally measures the position error using a moving-sum algorithm and judges each pin’s type by gray level. The new method uses the gray level statistic information to solve the empty pad problem and utilizes the symmetrical property of a circle to deal with the shape problem. Lastly, the cyclic redundancy check (CRC) algorithm is used to check the correspondence between each pin and its pin type. This new method has a high accuracy and reduced execution time and meets the crucial time requirement of a high-speed SMT machine through experimental verification.     

基于深度图像的SMT焊膏印刷实时自动检测

表面贴片安装技术(SMT)焊膏印刷质量机器视觉检测中,对采集的图像直接分割精度不高,而印制电路板(PCB)的焊盘、焊膏印刷模板中包含了焊膏的位置和高度信息,利用其建立标准模板节省了统计建模时间。通过焊膏印刷前裸印制线路板(PWB)的数字图像差运算来获取焊膏分割图像,大大提高了检测精度和速度。图像的形态学处理可以消除图像间的正常偏差噪声。图像深度值的提取是利用和无激光的背景图像的差运算。对比实验证明了本方案的检测准确度和速度都有较大提高。     

新产品导入流程及SMT车间管理与质量控制概述

针对新产品的导入过程、车间现场管理及质量控制技术进行了全面的阐述。尤其是对新产品导入过程中的SMT生产线配置原则、设备选择,车间基础设施要求及生产现场管理,质量控制技术等几个主要方面重点分析。为了更好地提高产品质量和生产效率,使企业赢得较高的经济效益,从人员技术培训、设备与工具管理、材料技术采购、工艺设计与流程控制等因素出发,使产品生产系统步入良性循环。     

实现BGA的良好焊接

实现BGA的良好焊接是摆在所有SMT工程技术人员面前的一个课题，从BGA的保存，使用环境以及焊接工艺等方面对BGA焊接质量的影响进行评估。提出建议。针对如何实现BAG的良好焊接给出了有价值的解决方案。     

设计SMT焊盘应注意的若干问题

针对在新产品开发中，SMT印制电路板上常见的影响焊接质量的焊盘设计中的失误，归纳并提出务必特别注意的若干问题。     

Grouping SMT PCB Assembly using FCM Algorithm

１IntroductionOneofthecharacteristicsoftheelectronicindustriesinHongKongisitsflexiblemanufacturingenvironment．Thetypeofproductionistypicallyalowvolume熏highmixtype．Lowvolumemeanstheproductionforeachbatchofproductionisrathersmall熏typically５００－５０００unitsperbatch．HighmixmeansthevarietyoftheproductionislargeandmanydifferenttypesofPCBsareproducedatthesametime．Insuchsituation熏thechangeoverfromonetypeofPCBtoanothertypeisquitefrequentandun鄄avoidable．ButthetimewastedinchangingPCBty…     

微电子器件在雷达接收机中的应用

本文叙述了现代战争对雷达接收机以及微电子化的迫切要求，具体列出了对ＭＭＩＣ、ＡＳＩＣ、ＦＰＧＡ、ＳＭＴ微组装器件的要求以及目前国内外的先进水平，同时列举了作者单位应用微电子技术的历史及现状。     

数字BP机生产中的SMT技术及工艺

表面贴装技术（ＳＭＴ）是当代先进的电子组装技术，本文从工艺方案的确定至具体工艺实施，对ＳＭＴ技术在ＢＰ机生产中的应用开发作了介绍，最后总结了ＳＭＴ应用于ＢＰ机的优点。