Si微波功率晶体管加速寿命试验夹具的设计

温度应力的加速寿命试验结果与所用夹具的耐温性及壳温的精确测量与控制直接相关。通过大量研究,发现一体式夹具在试验壳温提高到某一值时性能迅速劣化,因此设计符合高温下使用的分离式夹具是加速寿命试验顺利进行的必要条件。提供了两种加速寿命试验夹具的设计思路,并用于Si微波功率管加速寿命试验,通过步进应力试验和恒定应力试验,获取了该Si微波功率管加速寿命。分体夹具可耐受的试验温度在260℃以上,为加速寿命试验提供了温度应力的提升空间。     

光电设备振动夹具的设计探析

夹具在光电设备的振动试验中起着关键性的作用，决定着振动试验的效果．运用牛顿定律及微积分对振动夹具的力学传递性进行了推算，结合实际试验中的经验进一步分析了光电设备振动试验对夹具的要求，并着重对光电设备的振动夹具设计原则、设计步骤和鉴定方法进行了初步探讨。     

快速成形技术在检验夹具中的应用

本文介绍了当今世界先进的快速成形技术在检验夹具中的应用和发展前景，重点分析了传统的设计制造程序和快速成形技术设计制造程序的不同，并介绍了新材料在检验夹具中的应用，对两种设计制造方法进行了比较，总结了快速成形技术设计制造检验夹具的特点。     

基于筛选试验的集成电路外观缺陷探究

筛选试验是包含温度应力、电应力、机械应力的多种试验，能够有效地剔除设计和制造方面存在缺陷的集成电路，是集成电路应用高可靠性的重要保障。若筛选试验的条件方法、操作和工装夹具等选择不当，可能会使得集成电路外观产生缺陷，常见的缺陷有掉标、引脚变形、瓷损和沾污等。筛选试验的目的是减少存在的缺陷，试验过程中产生外观缺陷是不可接受的，也是质量管控的重要要求。因此，通过对筛选试验过程中的外观缺陷进行分析，探究了筛选试验中影响外观的因素，以减少质量事件的发生，保证集成电路的可靠性。     

变压真空发泡设备夹具调节机构设计

介绍了变压真空发泡技术,分析了现有变压真空发泡设备夹具侧板调节机构存在的问题,结合变压真空发泡设备夹具侧板的结构特点,设计一种新的变压真空发泡设备夹具调节机构,该调节机构能在生产时将冰箱发泡力通过两侧板传递到两丝杆上,转化为丝杆内力并实现宽度方向对称运动的功能,不仅有效减少了人为因素,还大大提高了工作效率和冰箱发泡质量,为推广其他产品发泡设备的技术改进提供一定参考依据。     

振动试验夹具的设计

夹具是振动试验常用的工件之一，它的刚度、质量、重心的定位等动态特性参数是影响产品试验真实再现的重要因素。介绍了夹具的设计原则，提出了夹具设计中常见的问题和注意事项，并介绍了相关夹具的测试方法。     

光学小卫星振动夹具设计及动特性分析

夹具是卫星振动试验的传力部件,夹具性能的好坏直接影响到振动试验的真实性和可靠性。总结了卫星振动夹具设计的一般方法和思路,针对某光学小卫星振动夹具进行了设计工作,利用有限元软件MSC.NASTRAN对振动夹具动特性进行了分析,对其刚度、质量、固有频率及动特性响应间的关系进行了研究,完成了某光学小卫星振动夹具的设计工作,从其动特性响应分析结果看,带振动夹具后整星动特性响应平均偏差约为6%,最大响应偏差约为11%,振动夹具对整星动特性影响在合理范围内,目前该振动夹具已成功应用于某光学小卫星按GJB1032-90所规定的地面力学环境试验中,并取得了预期的效果,该方法可应用于其他卫星振动夹具的设计中。     

空间光学遥感器振动夹具的设计与研究

力学振动试验是验证空间光学遥感器动力学特性的重要手段,而振动试验所需要的夹具在光学遥感器的振动试验中起着重要的作用,决定着振动试验的效果。本文运用振动理论分析了夹具对试验准确性的影响,并简要阐述了夹具设计的基本原则;针对空间光学遥感器,从材料选择、加工制造方法及结构形式等方面对夹具进行了设计,先后选择了两种结构方案形式;运用NASTRAN软件对两种方案的夹具的有限元模型进行了模态分析,最终选择了夹具方案二的结构形式,其一阶频率为451Hz;通过力学试验对夹具进行了鉴定,获得了夹具的正弦特征扫描曲线,试验得到夹具的一阶固有频率为398.7Hz,满足相机力学试验对夹具的要求。最后,对工程分析和试验的误差来源进行了分析,并提出了夹具设计时应该注意的一些问题。     

基于机械臂与U盘的文件自动传递系统

<正>在联网计算机和非联网计算机之间进行文件传递是一项重复性强且耗费人力的工作，现有基于机械臂与光盘的自动化解决方案会产生大量的光盘损耗，浪费资源。针对这一问题，提出了基于机械臂和U盘的文件自动传递系统。使用弹性材料设计了U盘和USB扩展坞的固定夹具，降低了对机械臂定位精度的要求。设计了完整的系统软件，实现机械臂的运动控制、邮箱附件的自动下载、文件的自动移动与杀毒等功能，实验验证了所设计系统的有效性。     

齿轮加工夹具设计探讨

本文介绍了滚齿夹具、剃齿夹具、刨齿夹具、插齿夹具的设计要点和典型结构分析,并叙述了设计齿轮加工夹具时,定位尺寸的选取原则和精度的配合类型。     

结构振动试验转接器的设计及安装问题

一些产品及其相关部件在作振动试验时，由于产品的外形或特殊要求不能直接安装在振动台面上，需要通过特别设计的转接器（夹具）来进行连接，这种夹具实际上是一种附加结构，它作为台面与试件之间的中介，如设置不当将影响振动试验结果的可靠性。本文通过对某事例的分析与研究，从试验频带、允许误差、跟随条件以及安装共振频率等方面阐明与讨论了相关夹具的特性、设计原则与安装等问题。     

The optimization of on-wafer shield-based test fixture layout

The effect of layout design on shield-based test fixture parasitic components is studied in this paper. As a result, guidelines for shield-based test fixture layout design are given. The novel test fixture layout details studied in this paper are a slotted ground plane with different slot orientation, the use of ground-bar extensions in a ground-shielded test fixture, and the upgrade of a ground-shielded test fixture to a fully shielded structure with a common ground. It was found that a slotted ground plane does not increase the ground lead impedance significantly. Thus, successful ground-shielded test fixture processing can be ensured by obeying process stress release design rules. Furthermore, the additional ground bar extensions had a negligible effect on reducing the ground-shielded test fixture ground lead impedance. However, upgrading the ground-shielded test fixture structure to fully shielded reduced the ground lead impedance. Therefore, fully shielded test fixtures are proposed for use with two-port cascade-based deembedding methods, which commonly are incapable of taking into account ground lead parasitic components.     

动车悬挂式电气设备通用振动试验夹具设计

针对设备振动试验夹具无法通用的现状,从设备的实际安装方式与试验条件出发,设计了符合动车悬挂式电气设备通用安装的振动试验夹具．并通过仿真分析与实验测试．验证了通用夹具满足振动试验的要求。从而缩短了夹具设计制作周期,节约了加工成本,大大提高了试验效率。     

An experimental study of scalability in shield-based on-wafer CMOS test fixtures

In this paper, the possibilities of employing full scalability to on-wafer complementary metal-oxide-semiconductor (CMOS) test fixtures is studied experimentally. Several test fixtures and in-fixture sets were fabricated and measured in order to find the significant parasitic components in shield-based fixtures. An improved method for applying bi-directional scaling to on-wafer shield-based test fixtures is proposed. This method takes into account the parasitic series resistance, series inductance, and parallel capacitance that are present in the test fixture. The proposed method can be used successfully in commonly known deembedding methods. This is verified through measurements. The test fixtures were fabricated on top of a lossy substrate using double-poly, three-metal-layer 0.35-/spl mu/m CMOS technology.     

大型空间遥感器动力学试验

大型空间遥感器结构复杂、重量大,在研制过程中,给地面动力学环境试验工装的设计带来很大的困难.振动工装是振动试验的传力部件,将振动台与遥感器连接起来,其性能直接影响到振动试验的真实程度和可靠程度.本文论述了遥感器振动工装研制及动力学试验过程.正弦振动和随机振动结果表明,振动台的振动输入条件与工装对遥感器的输入条件基本一致...     

RF electrical measurements of fine pitch BGA packages

A series of fine pitched ball grid arrays (BGAs) were measured on an Network Analyzer using a novel technique to de-embed the package test fixture and provide an accurate representation of the electrical characteristics of the package. The technique consisted of the design and fabrication of a RF circuit board. Duplicates of the board were modified to become a series of calibration fixtures while others, with sample packages attached, were modified to become test fixtures. The packages, attached to circuit boards, were measured to determine their performance at the RF frequencies of most cellular phone applications. Measurements included the return losses looking into several leads of the package that were 50 Ω terminated and insertion losses from one terminated lead to an adjacent one. These measurements can be used for verifying models or for characterizing packages     

Calibration of current transducers at high frequencies

The transfer impedances of current transducers are estimated using a special calibration fixture, which is often assumed to be perfectly matched at its coaxial ports. However, the errors inherent in this approximation increase with frequency, making the measurement of cable currents increasingly inaccurate at higher frequencies. A one-dimensional (1-D) transmission line model is proposed to account for such errors in a calibration fixture of simple design by using additional measurements to quantify the mismatches in the system. This technique is validated using a numerical model of such a calibration fixture as well against experimental data and numerical predictions for the current induced on a wire inside a rectangular cavity due to an external source that is coupled into the interior via an aperture. It is concluded that the proposed approach provides improved results with a calibration fixture of simple design for frequencies up to at least 600 MHz     

电子设备板级振动测试工装设计

本文对电子设备板级常用振动测试工装的形式、特点、结构进行了简要介绍,说明了板级振动测试工装的设计要点及注意事项,并重点对振动测试插箱的设计过程进行了详细介绍,可对板级振动测试工装结构设计提供有效的技术指导.     

浅谈环境可靠性试验管理中的若干工艺技术应用问题

在电真空器件环境试验中经常要遇到各种工艺问题,特别是在力学环境试验中,工艺性与技术性要求很强的就是模夹具设计问题,这种模夹具实际上是作为被试件和台面的联接中介,它的合理设计与安装决定了试验结果的真实性、被试件的安全性以及可靠性.本文结合具体实例来阐明设计原则,针对振动、冲击、碰撞等各个力学环境试验的具体要求和被试件的实际,综合考虑来提高效率、降低成本.