一个5-bit 4 GS/s的插值型模数转换器设计

设计了一款5-bit 4 GS/s的电阻插值型模数转换器(ADC),由预放大器阵列、高速比较器和编码器模块组成。定量分析了预放大器阵列的带宽和增益对ADC性能的影响,选取了最优的预放大器阵列结构,采样保持电路则选择了分布式采样,并采用电流逻辑模(CML)的比较器和编码电路。基于TSMC 65 nm工艺下进行仿真:在4 GHz的采样频率下,输入信号为200 MHz时,有效位数(ENOB)为4.85,SNDR为30.97,系统功耗为85 m W。     

一种具有失配校准技术的轨到轨输入逐次逼近型模数转换器设计

传统的逐次逼近型模数转换器很难对输入等于电源电压的模拟信号进行正确的模数转换,本文提出了一种新型的逐次逼近型模数转换器,能够对输入幅度等于电源电压的输入信号进行正确的转换,并且具有用于缩短采样时间的采样保持放大器电路,同时针对比较器失调和电容阵列失配提出了校准技术,进一步提高了转换精度。测量结果显示该模数转换器的最大信噪谐波失真比可以达到72dB,有效输入信号带宽为1.25MHz,消耗功耗为1mW,相应的FOM指数为123fJ。     

Simulink环境下的SAR ADC行为建模与仿真分析

逐次逼近型模/数转换器由于电路复杂度较低,且功耗和速度等性能可以随着集成电路工艺的进步而不断提升,在高速、高精度ADC设计中被广泛应用。借助Matlab软件环境下的Simulink工具,该文以14位SAR ADC为例给出了电路的行为级建模方法,分析了SAR ADC采样频率、输入信号频率以及内部时钟之间的关系,充分讨论了Simulink下各模块的具体实现并给出了仿真结果。该分析为SAR ADC的晶体管极电路设计与实现提供了重要参考依据。     

一种14位85 MS/s流水线型ADC

基于0.18μm CMOS工艺设计与实现了一种14位85 MS/s流水线型模数转换器(ADC)。采用多种低功耗设计技术来降低系统功耗和面积,包括无采样保持电路前端和运算放大器共享等技术。在无数字校准的条件下,在3.3 V电源电压、85 MHz的时钟频率和70 MHz正弦输入信号频率下,达到了67.9 dBFS的信噪比(SNR)以及82.2 dBFS的无杂散动态范围(SFDR)。该ADC功耗为322 mW,面积为0.6 mm²,适合用于需求低功耗ADC的通信系统中。     

事件驱动型的模数转换器设计

本文提出了一种适用于医疗信号处理的事件驱动型模数转换器(Level Crossing ADC)的电路,电路去掉了传统ADC固有的采样模块,采用1-bit DAC电路,低电源电压的架构.本设计采用SMIC 0.18μm CMOS工艺,电源电压为0.8V,单输入通道,在MATLAB的数据处理结果表明,整个电路共消耗功耗为0...     

12 bit 200 MS/s时间交织流水线A/D转换器的设计

介绍了一款应用于无线收发系统的12 bit 200 MS/s的A/D转换器(ADC).流水线型模数转换器是从中频采样到高频采样并且具有高精度的典型结构,多个流水线型模数转换器利用时间交织技术合并成一个模数转换器的构想则是复杂结构和能量利用率之间的折中选择.采用了时间交织、流水线和运算放大器共享等技术,既提高了速度和精度,也节省了功耗.同时为了减小时序失配对时间交织流水线ADC性能的影响,提出了一种对时序扭曲不敏感的采样保持电路.采用SMIC 0.13 μm CMOS工艺进行了电路设计,核心电路面积为1.6 mm×1.3 mm.测试结果表明,在采样速率为200 MS/s、模拟输入信号频率为1 MHz时,无杂散动态范围(SFDR)可以达到67.8 dB,信噪失真比(SNDR)为55.7 dB,ADC的品质因子(FoM)为1.07 pJ/conv.,而功耗为107 mW.     

低电压低功耗CMOS采样保持电路

设计了一个用于流水线型模数转换器的低压采样保持电路。为降低采保电路中运放的功耗,本文采用了增益补偿的采样保持电路结构,从而用简单的低增益运放达到高精度的效果。并从运放输出建立时间的角度对其输入电流进行优化。为了提高精度,降低采样开关的电阻并减小非线性误差,设计了信号相关自举电压控制的开关。仿真结果表明在1．8V的电源电压下,达到10bit的精度和50Mbit的采样率,整个采保电路的功耗仅为2．3mW。     

一种新型双采样CMOS采样保持电路

应用改进的双采样技术设计了一个标准CMOS模拟工艺下、采样率为80MHz的采样保持电路.应用单一时钟控制采样以消除两相采样的不匹配;采用时钟控制的双输入端运放以消除存储效应并消除大部分失调;采用栅压自举的采样开关以减小非线性失真.仿真结果表明,在2.5V电源电压下,当输入信号频率为37MHz时,采样保持电路可获得11bit的精度,消耗13mW的功耗.     

基于SiGe BiCMOS工艺的8GS/s采样保持电路

为实现数字通信对高速模数转换器的要求,基于0.18μm SiGe BiCMOS工艺提出了一款8 GS/s采样率、6 bit的采样保持电路。电路采用全差分开环结构,利用射极跟随型采样开关实现了电路高采样率。采样开关中采用晶体管线性补偿技术,有效地提高了采样保持电路的线性度。输出缓冲电路采用级联结构实现高线性度,并提高了电路的驱动能力。测试结果发现,在采样模式下单端输入信号频率4 GHz、采样时钟频率8 GHz条件下,有效位数为5.4 bit,无杂散动态范围为37.6 dB,总谐波失真为37.5 dB,总功耗为450 mW,芯片尺寸为0.68 mm×0.68 mm。     

0.13 μm CMOS 60 dB SFDR的8 bit 250 MS/s模数转换器

论述了一种高速度低功耗的8位250 MHz采样速度的流水线型模数转换器(ADC).在高速度采样下为了实现大的有效输入带宽,该模数转换器的前端采用了一个采样保持放大器(THA).为了实现低功耗,每一级的运放功耗在设计过程中具体优化,并在流水线上逐级递减.在250 MHz采样速度下,测试结果表明,在1.2 V供电电压下,所有模块总功耗为60 mw.在19 MHz的输入频率下,SFDR达到60.1 dB,SNDR为46.6 dB,有效比特数7.45.有效输入带宽大于70 MHz.该ADC采用TSMC 0.13μm CMOS 1P6M工艺实现,芯片面积为800 μm×700μm.     

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.