输入保护设计典型应用

论述了CMOS集成电路 ESD保护的必要性.接着介绍了CMOS集成电路ESD保护的各种设计技术,包括电流分流技术、电压箝位技术、电流均衡技术、ESD设计规则、ESD注入掩膜等,采用适当的ESD保护技术,1.2μm CMOS集成电路的ESD能力可以达到2000V.     

一种新型HERIC光伏逆变器漏电流抑制技术研究

针对已有的无变压器光伏逆变器存在共模电压威胁人身安全的问题,在非隔离光伏逆变器(Highly Efficient Reliable Inverter Concept,HERIC)拓扑的基础上,提出了一种新型的箝位型HERIC拓扑。箝位型HERIC拓扑是在逆变器直流输入电容的中点加入了另一个开关管,使整个工作过程中共模电压保持不变。通过仿真发现这一理论是可行的。然后分别搭建HERIC逆变电路和箝位型HERIC逆变电路,通过对比实验和数据分析验证了仿真结果,证明了箝位型HERIC拓扑的有效性和低漏电流特性。     

单板机快速复位电路

<正> 本刊1988年第2期刊登了李秀山同志的《高可靠Z80CPU启动电路》。这篇文章所介绍的电路,解决了一个我们经常忽视的实际问题。但此电路也存在着不足。首先,为了使电路在低于+5V电压范围内正常工作,电路中倒相器采用了CMOS电路。但是CMOS电路输入端不宜接大容量电容,否则,电容的充放电,易造成CMOS电路的损坏。其次,此电路较复杂,需要对原电路作不小的改动。为了解决这个问题,本人设计了如图1所示的电路,此电路可靠、简单,只需增加两个元件就可在单板机电路板上直接加装。     

衬底触发层叠式NMOS实现混合I/O静电保护机制研究

衬底触发技术可以大幅度提高大尺寸NMOS器件的ESD级别.将衬底触发技术融合到层叠式NMOS器件中来产生衬底触发层叠式NMOS器件,理论分析结果表明衬底触发技术可以提高混合电压I/O电路中层叠式NMOS器件的ESD稳健性,基于0.35μm CMOS工艺的模拟结果表明应用带有衬底触发技术的层叠式NMOS器件的HBM模型ESD级别提高约60%,这就验证了衬底触发设计对提高混合电压I/O电路的ESD级是有效的.     

高清多媒体接口的静电放电保护设计

通过对静电放电(ESD)保护原理的研究,合理地选取了瞬态电压抑制二极管的参数,在Multisim软件中对ESD的保护电路进行了模型仿真。利用瞬态电压抑制二极管分别设计出高清多媒体接口的最小化传输差分信号保护电路、电源保护电路以及电平转换保护电路,并建立了ESD人体放电模型来对电路进行仿真分析,仿真结果表明本设计方案可行。     

基于Saber的有源箝位反激电路设计与仿真

简述了反激变换器的电路结构及原理,提出了有源箝位反激电路,并对其工作过程进行了分析讨论。在此基础上对有源箝位反激电路的关键器件的参数进行了理论设计。基于Saber软件搭建了仿真模型,对分析结果进行仿真验证。仿真结果表明,引入有源箝位电路后,不仅使得隔离变压器漏感引起的能量传输损失得到了充分利用,而且使主辅功率开关器件实现软开关,有效地降低了功率开关器件电压应力和开关损耗,使得变换器的效率和可靠性得到了进一步提升。     

正反极组合有源箝位单端软开关电源研究

简要介绍一种有源箝位、正反激组合ZVS-PWM单端电路拓扑的软开关工作形成机理.在实验电路中,引入了一个单管辅助开关,并利用功率变压器的初级漏感及功率MOS管的寄生电容参与谐振,以实现电源工作的ZVS条件.辅助开关的引入还起有源箝位的作用,降低了主开关的电压应力.     

电磁脉冲环境下电源防护电路设计

主要设计了直流电源在强电磁脉冲环境下的保护电路,阐述了设计思路,并进行仿真和实验验证.防护电路设计采用瞬态元件和滤波电路互相配合使用.瞬态元件主要是电压箝位和电流的泄放,滤波电路是滤波和延时作用.仿真与实验结果表明,防护电路可以对强电磁脉冲进行衰减,可以有效保护直流电源.     

Ⅱ.具有限流的集成电路电压调整器

如果集成电路加一个具有外部程序反馈特性的过载保护电路,电压调整器就能够避免由于短路的功耗而毁坏。对于给定的插件的额定功耗值来说,在调整状态时反馈限流使输出电流最大,同时也可以把电流减到瞬时空载时的最小。     

CMOS大规模集成电路制造工艺

一.引言CMOS 集成电路即互补 MOS 型集成电路,系指在同一块半导体村底片上制造 n 型和 P 型两种不同导电沟道的 MOS 场效应晶体管,从而构成的集成电路。与 PMOS 及 NMOS 相比,CMOS 电路有一系列优点。CMOS倒相器在两种不同的逻辑状态下总有一个晶     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate