基于0.18μm工艺的I/O端口ESD防护设计

当两个拥有不同电势的物体接触时,电势差会导致电荷流动,从而产生放电,这种现象称为静电放电(Electrostatic Discharge,ESD)。ESD所产生的瞬间高电压和大电流,会烧毁击穿半导体中的器件,最终导致整个半导体芯片永久性失效。随着硅基CMOS工艺技术的不断进步,由ESD引起的失效问题也随着特征尺寸的变小而日益严重。首先分析了几种常见的静电放电模式以及测试模型,随后基于SMIC公司0.18μm BCD工艺,在传统GGNMOS抗辐照ESD结构基础上进行优化,设计一款GGNMOS+RC Power Clamp抗ESD结构。经流片测试后,证明该款电路抗ESD能力强,且性能稳定。     

非本征光纤F—P传感器制作工艺的研究

本文分析了非本征光纤F-P传感器制作工艺上存在的问题,对传感器工艺制作进行了研究.设计了半自动光纤F-P腔调节工作台,利用光纤五维调节架对光纤进行插入和对准,提高了光纤F-P传感器制作的速度和质量.     

PWM控制器UCC2580的原理和应用

本文介绍了PWH控制器UCC2580的基本原理及内部组成,详细说明了它的一种典型应用。     

Finite element analysis of the clamp band joint

In this paper, the clamp band joint commonly used to connect cylindrical shells with end flanges is modeled using the finite element analysis software ANSYS. The joint model is validated by a series of static experiments. Then the response of the joint components to the preload and the axial load is analyzed in detail, from which the axial load capability, the axial stiffness and the damping characteristics of the clamp band joint are discussed. Finally, parametric studies are carried out to investigate the effects of the preload, the wedge angle, the friction coefficient, and the number and size of the V-segment on the behavior of the clamp band joint. This paper presents the general mechanical behavior of the clamp band joint subjected to axial loads.     

基于STFOD结构的IC全芯片保护

在具有输入、输出静电保护的集成电路中,往往会出现非正常的静电损伤。这是由电源与地之间的静电压以及管脚之间的静电压通过内部电源线的放电而引起的。这种静电损伤给芯片的制造和使用带来了很大的困难。在基于传输诊测电路的电源到地NMOS ESD保护结构的基础上,设计了基于衬底触发场氧器件(STFOD)结构的箝位电路和版图,使芯片的静电等级得到大幅提高。     

Allosteric Regulation of Aptamer Affinity through Mechano-Chemical Coupling**

The capacity to precisely modulate aptamer affinity is important for a wide variety of applications. However, most such engineering strategies entail laborious trial-and-error testing or require prior knowledge of an aptamer's structure and ligand-binding domain. We describe here a simple and generalizable strategy for allosteric modulation of aptamer affinity by employing a double-stranded molecular clamp that destabilizes aptamer secondary structure through mechanical tension. We demonstrate the effectiveness of the approach with a thrombin-binding aptamer and show that we can alter its affinity by as much as 65-fold. We also show that this modulation can be rendered reversible by introducing a restriction enzyme cleavage site into the molecular clamp domain and describe a design strategy for achieving even more finely-tuned affinity modulation. This strategy requires no prior knowledge of the aptamer's structure and binding mechanism and should thus be generalizable across aptamers.     

集成电路测试系统的加流测压及加压测流设计

在集成电路的测试中,通常需要给所测试的集成电路提供稳定的电压或电流,以作测试信号,同时还要对信号进行测量,这就需要用到电压电流源;测试系统能作为测试设备的电压电流源,实现加压测流和加流测压功能。且具有箝位功能,防止负载电压或电流过大而损坏系统。应用结果表明,该检测系统运行稳定可靠,测量精度高。