一种AB类输出的高精度CMOS正向电流传输器

基于CSMC 0.5 μm工艺,在两级CMOS运放的基础上,设计了一种结构简单、电压跟随能力强和电流传输精度高的第二代正向电流传输器(CCII ).设计中,通过采用AB类推挽输出方式,达到了降低静态功耗和提高电流驱动能力的目的;应用密勒电容与调零电阻串联的补偿方式,有效地改善了CCII 的频率响应特性;分析了AB输出级晶体管对静态电流的影响.HSPICE仿真结果表明,在1.5 V供电电压下,该CCII 的电压跟随误差仅为0.0534 dB,-3 dB带宽达到201 MHz;电流传输误差为0 dB,-3 dB带宽达到54.4 MHz,X端输入电阻低于0.57 Ω,电流驱动能力为-0.2～1.2 mA,电路功耗为2.54 mW.     

一种新型低压高电流驱动能力的CMOS电流传输器

设计了一种电压和电流跟随能力强,低压驱动性能好的第二代电流传输器.采用SMIC 0.18 μm工艺,利用Spectre对整个电路进行了仿真.电源电压为1.8 V,输入级采用轨对轨的结构,有效地提高了信号的摆幅;输出级采用AB类推免输出方式,在降低电路功耗的同时,也提高了电流的驱动能力.通过采用MOS管与电容串联的补偿方式,有效地改善了CCII+的频率响应特性.仿真结果表明,该CCII+的-3 dB带宽达709 MHz,X端输入电阻低于100 Ω,电流驱动能力为0.05 mA-2.5 mA,电路功耗为140 μW.     

高增益低功耗恒跨导轨到轨CMOS运放设计

基于CSMC的0.5μmCMOS工艺,设计了一个高增益、低功耗、恒跨导轨到轨CMOS运算放大器,采用最大电流选择电路作为输入级,AB类结构作为输出级。通过cadence仿真,其输入输出均能达到轨到轨,整个电路工作在3 V电源电压下,静态功耗仅为0.206 mW,驱动10pF的容性负载时,增益高达100.4 dB,单位增益带宽约为4.2MHz,相位裕度为63°。     

基于MOCCⅡ的低压低功耗自偏置CCⅢ的设计

采用TSMC0.35μm工艺参数,基于多输出端第二代电流传输器(MOCCⅡ)提出了一种新型CCⅢ电路,电路采用轨对轨的输入结构,有效地提高了信号摆幅;通过电路内部晶体管提供偏置,达到了减少芯片面积和降低功耗的目的。HSPICE仿真结果表明,在±1 V供电电压下,该CCⅢ的电压跟随误差为0.06 dB,-3 dB带宽为434.3 MHz;端口Y与X之间的电流跟随误差为0.06 dB,-3 dB带宽为381.2 MHz;端口Z+与X之间的电流跟随误差为0.02 dB,-3 dB带宽为334.1 MHz;端口Z-与X之间的电流跟随误差为0.05 dB,-3 dB带宽为665.8 MHz;整体电路的功耗为2.133 mW。据CCⅢ电路设计了一种电流模式带通二阶滤波器,结果与理论值较吻合。     

一种恒跨导轨对轨输入/输出CMOS运算放大器

设计了一种CMOS恒跨导轨对轨输入/输出运算放大器,输入级采用负反馈技术控制尾电流,能自调整gm并使之保持恒定;输出级采用前向偏置AB类输出结构,实现轨对轨输出的同时减小了静态功耗。整个电路在5 V电源电压下,电压增益达到136 dB(1 MΩ电阻和1 pF电容并联负载),单位增益带宽为9.7 MHz,相位裕度62.4°。     

基于MOCCII的低压低功耗自偏置CCIII的设计

采用TSMC 0.35 μm工艺参数,基于多输出端第二代电流传输器(MOCCⅡ)提出了一种新型CCⅢ电路,电路采用轨对轨的输入结构,有效地提高了信号摆幅;通过电路内部晶体管提供偏置,达到了减少芯片面积和降低功耗的目的.HSPICE仿真结果表明,在±1V供电电压下,该CCⅢ的电压跟随误差为0.06 dB,-3 dB带宽为434.3 MHz;端口Y与X之间的电流跟随误差为0.06 dB,-3 dB带宽为381.2 MHz;端口Z+与X之间的电流跟随误差为0.02 dB,-3 dB带宽为334.1 MHz;端口Z-与X之间的电流跟随误差为0.05 dB,-3 dB带宽为665.8 MHz;整体电路的功耗为2.133 mW.据CCⅢ电路设计了一种电流模式带通二阶滤波器,结果与理论值较吻合.     

低压工作的轨到轨输入／输出缓冲级放大器

本文提出了一种低压工作的轨到轨输入／输出缓冲级放大器。利用电阻产生的输入共模电平移动,该放大器可以在低于传统轨到轨输入级所限制的最小电压下工作,并在整个输入共模电压范围内获得恒定的输入跨导;它的输出级由电流镜驱动,实现了轨到轨电压输出,具有较强的负载驱动能力。该放大器在CSMCO．6-μmCMOS数模混合工艺下进行了HSPICE仿真和流片测试,结果表明：当供电电压为5V,偏置电流为60uA,负载电容为10pF时,开环增益为87．7dB,功耗为579uw,单位增益带宽为3．3MHz;当该放大器作为缓冲级时,输入3VPP10kHz正弦信号,总谐波失真THD为53．2dB。     

一种微功耗轨到轨输出AB类运算放大器设计

在分析研究AB类运算放大器的输入和输出级构成原理基础上,提出一种与信号处理模块的输出端匹配并具有一定负载能力的缓冲器的设计。缓冲器采用了AB类运放结构,其输入级采用折叠式共射共基结构,输出级分别采用PNP管和NMOS管作为上拉管和下拉管,结合电路结构的改进使之具有轨到轨(rail-to-rail)的输出特性和很低的静态电流。设计的电路具有开环增益大、静态功耗小、带宽较高等特点。此运放已在1.5μmBCD工艺下实现。测试结果表明,静态电流仅为8.5μA,闭环带宽达200kHz,开环增益为100dB。     

低功耗轨至轨CMOS运算放大器设计

设计了一个1.5 V低功耗轨至轨CMOS运算放大器。电路设计中为了使输入共模电压范围达到轨至轨性能,采用了NMOS管和PMOS管并联的互补差动对输入结构,并采用成比例的电流镜技术实现了输入级跨导的恒定。在中间增益级设计中,采用了适合在低压工作的低压宽摆幅共源共栅结构;在输出级设计时,为了提高效率,采用了简单的推挽共源级放大器作为输出级,使得输出电压摆幅基本上达到了轨至轨。当接100 pF电容负载和1 kΩ电阻负载时,运放的静态功耗只有290μW,直流开环增益约为76 dB,相位裕度约为69°,单位增益带宽约为1 MHz。     

一种0.8V衬底驱动轨对轨运算放大器设计

采用衬底驱动技术设计低压低功耗轨对轨运算放大器。输入级采用衬底驱动MOSFET,有效避开阈值电压限制,将电源电压降至0.8V,实现低压下轨对轨共模输入范围。增加衬底驱动冗余差分对及反折式共源共栅求和电路实现恒定跨导控制,消除共模电压对输入级跨导的影响,输出采用前馈式AB类输出级,以提高动态输出电压范围。基于标准0.18μmCMOS工艺仿真运放,测得输出范围0.4～782.5mV,功耗48.8μW,电源抑制比58dB,CMRR65dB,直流开环增益63.8dB,单位增益带宽2.4MHz,相位裕度68°。版图设计采用双阱交叉空铅技术,面积为97.8μm×127.6μm。     

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.