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1.
在掌握Protel99电路原理图设计和于工绘制PCB板的基础上,利用Protel99强大的设计功能自动设计PCB印删电路板,会大大提高我们的设计速度和效率,起到事半功倍的效果。  相似文献   

2.
电子方面的工程技术人员、大专院校师生、业余爱好者有时需要制作电路板。其中用预涂布感光敷铜板(文中简称感光敷铜板)制作印刷电路板的方法称为光印法。但在购买感光敷铜板时需要注意分清两种不同性质的感光材料,一种为正片感光材料,另一种为负片感光材料。两种不同的感光材料所要求的显影剂的性质不同,购买时不能混淆。而且,两种不同感光敷铜板要求的光印图是不同的。正片感光材料要求正片PCB图,负片感光材料则要求负片PCB图。通常EDA制图软件给出的是正片PCB图,如何用EDA制图软件设计负片PCB图?这是很多业余电子爱好者经常碰到的问题。本文以数字集成芯片组成的数字钟(单面PCB)为例,介绍基于Prote199 SE的负片感光敷铜板的PCB设计方法。  相似文献   

3.
由Biwin Electronic双胜电子出品的Kingforce金佛内存是一款很有特色的高端SDRAM产品。金佛内存的制造工艺很精湛,宽大的PCB板采用6层增强型PCB设计,具备优秀的电气性能,走线清晰,内存IC使用独特的BLP封装,更小更薄的IC的好处就是使得产品工作时的热量更小,运行更稳定。内存的IC上同样印的是双胜电子的标志,产品编号KFM28VB64168P-50,  相似文献   

4.
利用Cadence软件的Allegro系统互联平台可以完成PCB设计流程。PCB设计从原理图输出到PCB设计环境中开始,并由原理图设计来约束、决定。该文介绍了在Allegro SPB15.2版本中,利用CaptureCIS和PCB Editor互联平台进行PCB设计的方法和流程。  相似文献   

5.
Ilove 《微型计算机》2010,(3):162-163
在上一期我们已经为大家介绍了PCB结构基础知识、以及观察PCB层数的一些方法,存本期我们将继续为大家介绍PCB其它方面的一些相关知识,比如为什么PCB会有不同的颜色?不同颜色的PCB会影响性能吗?PCB上镀金和镀银、镀铜有什么差别,对于这些问题枸为你一一揭开。  相似文献   

6.
电容器在电子电路中有重要而广泛的用途。与传统的PCB设计相比,高速高密度PCB设计面临很多新挑战,对所使用的电容器提出很多新要求。此外,电容器技术和高速高密度PCB设计技术又都在不断发展。因而在高速高密度PCB设计中,电容器的选择是一个值得研究的问题。结合高速高密度PCB的基本特点,分析了电容器在高频应用时主要寄生参数及其影响,指出了需要纠正或放弃的一些传统认识或做法,总结了适用于高速高密度PCB的电容器的基本特点,介绍了适用于高速高密度PCB的电容器的若干新进展。  相似文献   

7.
罗雪飞 《福建电脑》2008,24(10):198-198
本文通过PCB实践教学研究和探索,结合我校近年来在实验教学改革的实践,探讨了提高学生制作PCB板水平和效率.介绍了PCB制作过程的工艺流程。  相似文献   

8.
针对工业生产中的PCB图像边缘信息缺失且携带有大量噪声,现有去噪算法效果不佳、计算量庞大、复杂度高等问题,提出了一种基于改进NLM的PCB图像去噪算法,旨在提高PCB图像的去噪质量.首先,采用基于形态学的权重自适应算法对PCB图像进行图像增强,使PCB图像保留较好的边缘信息;其次,引入特征匹配模型对增强后的PCB图像与原始PCB图像进行特征点匹配融合;最后,通过改进NLM算法的权重值对PCB图像进行去噪,得到最终的去噪图像.实验结果显示,与现有算法相比,所提算法更好地保留了PCB图像的边缘信息,去噪效果佳,显著改善了图像质量,增强了图像的鲁棒性,且提高了计算速度,降低了算法复杂度.  相似文献   

9.
针对Altium Designer初学者使用此软件时修改PCB板外形、为板子添加自己喜爱的LOGO和PCB封装添加3D模型提供了一些方案,优化PCB外观,增加板子的可靠性,确保元器件在空间上互不干涉,PCB与产品包装外壳空间不形成干涉。  相似文献   

10.
高速高密度PCB设计中电容器的选择   总被引:1,自引:0,他引:1  
电容器在电子电路中有重要而广泛的用途.与传统的PCB设计相比,高速高密度PCB设计面临很多新挑战,对所使用的电容器提出很多新要求.此外,电容器技术和高速高密度PCB设计技术又都在不断发展.因而在高速高密度PCB设计中,电容器的选择是一个值得研究的问题.结合高速高密度PCB的基本特点,分析了电容器在高频应用时主要寄生参数及其影响,指出了需要纠正或放弃的一些传统认识或做法,总结了适用于高速高密度PCB的电容器的基本特点,介绍了适用于高速高密度PCB的电容器的若干新进展.  相似文献   

11.
焦健 《自动化信息》2011,(11):72-73
本文主要介绍了PCB印刷机作为SMT(表面贴装技术)关键设备的主要工作原理和工艺流程。采用台达多轴运动控制卡提高了系统的实时性,并且提高了自动PCB印刷机系统的定位精度和响应速度,使得自动PCB印刷机取得了很好的经济效益。  相似文献   

12.
This paper investigates the possibility of utilising an additive screen printing process with conductive ink and adhesive together with a degradable substrate to identify whether this process offers a viable alternative to current subtractive methods of PCB manufacture. Existing manufacturing equipment and production process were adopted in order to establish the compatibility of a sustainable and environmental friendly PCB with these processes. Experimental trials have shown that by using a stainless steel stencil 150 mm thick in conjunction with an MPM Ultraprint machine with a printing speed of 89 mm/s, a squeegee pressure of 0.97 bar and a downstop of 1.9 mm successful printing of the electrically conductive adhesive was achieved. It was also shown that the substrate was compatible with electronic placement technology and convection oven. Comparisons of the electronic assemblies to an industrial IPC standard illustrated that it is possible to develop a circuit, which is deemed acceptable under this standard. It can be concluded therefore that a screen printed conductive ink pattern, when printed on a degradable substrate can offer a viable alternative to current printed circuit boards and can be manufactured using existing technology and manufacturing processes.  相似文献   

13.
A K‐band (18‐27 GHz) antenna array is presented in this article. By deposing the quasi‐pyramidal‐horn upon a print circuit board (PCB), a traveling‐wave quasi‐pyramidal‐horn antenna is formed. Parasitic rings are introduced to decrease the quality factor for an extended bandwidth. The antenna element demonstrates impedance bandwidth 18.6 to 23.3 GHz. The gain is 10.3 dBi at 20.4 GHz with a stable radiation pattern. The impedance bandwidth of a 2 × 2 array is 18.3 to 22.7 GHz, with a maximum gain of 15.2 dBi at 20.4 GHz. The simulated and measured radiation patterns on E‐ and H‐planes at 20.4 GHz agree well. Taking advantage of the 3D printing technology, the quasi‐pyramidal horn is fabricated by selective laser melting using aluminum alloy for time‐saving and process simplicity. The proposed design highlights the hybrid usage of PCB and metallic 3D printing technology in fabricating microwave devices. It is a capable candidate for wireless communication.  相似文献   

14.
Polymer matrix composites (PMC) with barium titanate as high-k-active filler have high potential in embedded capacitors within a printing circuit board (PCB) enabling high permittivity values and low loss factors. These PMCs allows for the use of established polymer processing techniques like screen printing and curing, which are compatible to the established PCB-materials and shaping processes. In this work a process chain, starting with a material optimization of the nano-sized barium titanate, dispersed in an unsaturated polyester-styrene reactive resin, and a further specific process development, will be presented. With respect to the optimization of the individual process steps the flow behaviour of the uncured composite, the polymerization process and the dielectric properties were characterized comprehensively. Using a composite with a barium titanate filler load of 74?wt% allows for a dielectric layer formation by a modified screen printing technique. After capacitor mounting and composite curing an initial capacity density of 13.3?pF/mm2 could be achieved.  相似文献   

15.
Tactile sensors based on conductive polymers   总被引:1,自引:1,他引:0  
This paper presents results from a selection of tactile sensors that have been designed and fabricated. These sensors are based on a common approach that consists in placing a sheet of piezoresistive material on the top of a set of electrodes. We use a thin film of conductive polymer as the piezoresistive material. Specifically, a conductive water-based ink of this polymer is deposited by spin-coating on a flexible plastic sheet, giving it a smooth, homogeneous and conducting thin film. The main interest in this procedure is that it is cheap and it allows the fabrication of flexible and low cost tactile sensors. In this work, we present results from sensors made using two technologies. Firstly, we have used a flexible printed circuit board (PCB) technology to fabricate the set of electrodes and addressing tracks. The result is a simple, flexible tactile sensor. In addition to these sensors on PCB, we have proposed, designed and fabricated sensors with screen-printing technology. In this case, the set of electrodes and addressing tracks are made by printing an ink based on silver nanoparticles. The exhaustive characterization provides us insights into the design of these tactile sensors.  相似文献   

16.
回流焊接温度曲线控制研究   总被引:2,自引:0,他引:2  
随着集成电路产业的飞速发展,高集成度、高可靠性已经成为行业的新潮流。在这种趋势的推动下,SMT(表面贴装技术)在中国也得到了进一步的推广和发展。很多公司在生产和研发中已经大量应用了SMT工艺和表面贴装元器件。在SMT工艺中回流焊接是核心工艺,因为表面组装PCB设计,焊膏印刷和元器件贴装产生的缺陷,最终都将集中表现在焊接中。因此,如果没有合理可行的回流焊接工艺,前面任何工艺控制都将失去意义。  相似文献   

17.
运用参考比较法对机器视觉PCB裸板缺陷检测进行了研究。在相机摄像头下同一位置采集多幅标准PCB图像累加求平均值得到标准电路板图像,运用Harris角点算法进行标准电路板图像和待测电路板图像的配准,分别对标准电路板图像和待测电路板图像进行灰度变换、中值滤波、二值化、异或等图像处理检测出缺陷区域,然后通过形态学消除伪缺陷,实验证明,该检测方法有较高的准确率。  相似文献   

18.
随着电子技术的迅速发展,用于PCB行业的设备与技术也突飞猛进。飞针测试机作为判定PCB板的电气连接是否良好的PcB检测设备,可以准确无误地检测出PCB板上各点之间的开短路情况,从而发现PCB板上出现开短路错误的位置。而要对PCB板的物理通断进行电气测量,首先必须知道PCB板正确的物理连接(即PCB的网络分布)情况。文章将主要讲述如何利用一种图形区域填充的算法,从用于绘制PCB板的GERBER文件中获取PCB板的正确网络分布。  相似文献   

19.
Line balancing of PCB assembly line using immune algorithms   总被引:5,自引:0,他引:5  
Printed Circuit Boards (PCBs) are widely used in most electronic devices. Typically, a PCB design has a set of components that needs to be assembled. In a broad sense, this assembly task involves placing PCB components at designated location on a PCB board; fixing PCB components; and testing the PCB after assembly operation to ensure that it is in proper working order. The stringent requirements of having a higher component density on PCBs, a shorter assembly time, and a more reliable product prompt manufacturers to automate the process of PCB assembly. Frequently, a few placement machines may work together to form an assembly line. Thus, the application of more than one machine for component placement on a PCB presents a line-balancing problem, which is basically concerned with balancing the workload of all the machines in an assembly line. This paper describes the application of a new artificial intelligence technique known as the immune algorithm to PCB component placement as well as the line balancing of PCB assembly line. It also includes an overview of PCB assembly and an outline of the assembly line balancing problem. Two case studies are used to validate the IA engine developed in this work. The details of IA, the IA engine and the case studies are presented.  相似文献   

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