基于UVM的可重用SoC功能验证环境

现在系统级芯片(SoC)系统集成度和复杂度不断提高,验证环节消耗时间占用了芯片研发时间的70％,芯片验证已经成为芯片研发中最关键的环节.目前业界验证方法大多有覆盖率低和通用性差等缺点,基于上述原因提出了一种新的验证方法.与传统验证方法和单纯的通用验证方法学(UVM)不同,该方法结合系统级芯片验证和模块级验证的特点,并且融合UVM和知识产权验证核(VIP)模块验证的验证技术,且使用了SoC系统功能仿真模型以提高验证覆盖率和准确性.验证结果表明,同一架构系列SoC芯片可以移植于该验证平台中,并且可大幅缩短平台维护与开发时间,采用该验证方法的代码覆盖率为98.9％,功能覆盖率为100％.     

SDH芯片功能验证平台的设计与实现

集成电路芯片的规模不断增大，功能越来越复杂，设计验证工作量也越来越大，成为整个设计周期的“瓶颈”。文章针对同步数字体量（SDH）宽带交换芯片设计中的功能验证，设计了初步的SDH验证平台，提出了具有一定通用性的SDH芯片的功能验证方案和实现方法，包括分层的描述和验证方法，一系列标准测试数据和自动观测模拟结果的若干加速C程序。该平台已用于40Gbit／s交换芯片的功能验证，加速了验证过程，取得了满意的效果。     

基于UVM验证方法学的数字交换芯片验证平台

采用统一验证方法学(universal verification methodology,UVM)搭建验证平台,对数字交换芯片的功能进行验证[1]。由于数字交换芯片的数据处理量较大,验证平台产生受约束的随机激励来验证数字交换芯片的功能,并通过代码覆盖率和功能覆盖率来完善验证用例。仿真结果表明,通过该验证平台验证数字交换芯片的功能正确,功能覆盖率达到100%,并通过机台测试。     

八通道多协议串行通信控制器的功能验证

超大规模集成电路芯片的验证是一项复杂的任务,占据了整个芯片设计工作量的70%.实现了一款八通道多协议串行通信控制器芯片的功能验证,介绍了基于总线功能模型验证平台的建立方法,并根据此芯片的设计特点,研究了该芯片的验证策略,设计了验证平台,同时完成了芯片的后仿真和样片测试.实践证明,该验证策略具有较高的功能覆盖率,验证平台具有较好的复用性,对同类具有复杂通信协议电路的功能验证有一定的参考价值.     

数字集成电路的FPGA验证

在一个复杂的asic芯片设计中，动辄数百万门，如果已流片后回来的芯片无法正常工作，必将造成时问、金钱的极大损失，比如开发费用的成倍增加，市场先机的丧失等等；为避免以上情况，在流片之前需要做验证，除了采用软件仿真和形式验证是很不够的，还需做其他一些不同的验证，这些验证方法互相补充，以尽可能提高芯片验证的覆盖率，其中很重要的就是系统级的FPGA验证。由于FPGA验证系统与实际的系统很接近，在这样一个系统上，芯片运行的速度和实际系统可比拟甚至一样，这有助于发现一些出现概率很低的bug，很容易运行一些在软件仿真中不太实际的测试；其次，对于一个FPGA验证系统，可以把它视为一个实际芯片构成的系统，完全可以在此基础上利用各种开发工具开发出相应的测试平台和应用平台，这就使得芯片代码的验证与实际芯片的测试类似，并且用于代码验证的所开发的工具和测试向量完全可以用于流片回来后的产品测试，大大减小了工作量，提高了工作效率；     

VMT在USBD模块验证中的应用

在集成电路设计中,功能验证是主要的瓶颈之一.据估计,验证工作占设计工作开销的60%以上.Synopsys公司VMT(Vera验证模型技术)工具可减小验证的工作量、节约时间.文中描述了使用VMT对USBD(通用串行总线器件)模块的验证,验证了USBD部件符合协议规范、完成系统定义的要求,并对不同的数据传输方式进行比较.本设计已通过MPW(multi-project wafer)流片生产出实际芯片,其效果在实际的芯片上得到了验证,达到了设计的效果.     

基于PC与数据采集系统的DSP＆CPU芯片功能验证方案

随着现代超大规模集成电路设计、制造工艺的快速发展,芯片的测试与验证所需的费用也越来越高.针对这个问题,本文提出了一种数字芯片的功能验证方案,该方案充分利用了PC机的丰富资源和数据采集系统的强大功能,有效地降低了数字芯片功能验证的成本.作者成功地运用该方案对一个百万门级的DSP&CPU芯片进行了功能验证,实际应用证明,该方案使用灵活、可靠,并且可以大幅降低芯片验证所需的费用,为数字芯片的功能验证提供了可以借鉴的有效方案.     

PON结构航空总线协议芯片仿真验证方法

针对基于PON结构的FC_AE航空总线协议芯片的验证需求与功能特性,提出了一种基于RTL级组网功能仿真验证的方法,阐述该方法下仿真验证平台测试用例模块、参考模型模块、结果检测器模块、验证平台整合模块的实现原理,最后,采用该方法搭建了FC_AE协议芯片的仿真验证环境,完成该芯片的仿真验证.该方法基于多种语言自动化验证平台,可从系统级与芯片级双通道验证芯片功能,有效的提高了验证效率,缩短了整个设计验证周期,为芯片的成功投片提供了可靠的保证.     

加速Flash系列FPGA芯片功能验证方法

提出了一种加速闪存（Flash）系列现场可编程门阵列（FPGA）芯片功能验证方法。通过解析全配置位流,得到帧数据与svf文件的映射关系,根据验证用例赋值相应的配置位流,大大减少了大规模FPGA全芯片功能验证的配置时间,加速了仿真的速度,提高了仿真验证效率。该方法已成功应用于Flash系列FPGA芯片电路功能验证工程实践中。     

无源光网络系统中基于UVM的DBA验证

在第五代移动通信技术(5G)通信中，动态带宽分配(DBA)作为无源光网络的关键技术之一，随着其不断优化自身性能，芯片功能的复杂度日益增长，对其逻辑功能的验证显得尤为重要。文章提出了一种无源光网络中的DBA模块验证平台架构体系。该平台基于通用验证方法学(UVM)框架调用System Verilog(SV)参考模型，以少数用例覆盖大量场景，实现了对DBA流量需求和下发授权功能点的验证和结果自校验，寄存器转换级电路(RTL)代码覆盖率可达95%以上。仿真表明，该验证平台支持DBA的系统级验证，支持框架复用和自动化数据对比，可满足验证的各项需求，为DBA的性能测试提供了一个高效和全面的验证环境，大大提升了验证效率。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.