基于TMS320F2812和ADS8364的智能节点设计

介绍了以TMS320F2812和ADS8364为核心的智能节点设计,该节点不仅可以进行数据采集,还可以实现阈值报警、数字滤波、FFT变换等功能。并详细介绍了本设计的工作原理、硬件设计以及软件设计。     

基于ADS855x的智能电网全景监控模块设计

对电网进行全景监控是实现智能化调度和辅助决策的基础,以高速浮点DSP和ADS855x为核心器件设计了一种新型的智能电网监控模块。介绍了该监控模块的整体结构和功能划分,利用ADS855x系列AD芯片实现了16位、14位和12位ADC的软硬件全面兼容,兼顾了电网不同环节对数据采集精度的不同需求。详细阐述了交流模拟量采集电路的设计,包括互感器选择,ADS855x芯片管脚设置等。最后对监控功能软件的整体结构和模拟量有效值计算算法进行了介绍。     

基于TMS320F2812同步数据采集系统的设计

本文介绍了一种基于TMS320F2812DSP芯片与AD转换芯片ADS8365构成的高速、并行高精度数据采集系统,用于实现高速同步数据采集。主要内容包括两种芯片功能的介绍、硬件接口电路的设计及相关软件设计等。     

ADS1282及其在单通道地震数据采集单元中的应用

为满足高精度地震数据采集需要,设计一种以32位、高集成度模/数转换器ADS1282为核心,以高性能、低功耗微控制器MSP430F123为采集控制器的单通道地震数据采集单元,该单元可实现单通道地震信号的拾取、数据转换、存储及传榆功能.设计中充分利用ADS1282片上集成功能,配合相应的抗干扰措施,既简化了电路设计,也保证了采集信号的质量和系统的稳定性.该采集单元可适用于那些对功耗、体积、精度均有严格要求的应用场合.     

基于CAN总线的24位数据采集子站节点设计

采用ADS1252与带有CAN控制器的单片机C8051F040设计了一种具备24位数据采集性能的高精度CAN接口数据采集子站,该设计适合于对1~8通道DC-10kHz信号的采集,提高了数据采集模块的采集精度,并且使数据采集模块具有了远程通讯的功能。从而使得数据采集模块具有了更优良的性能,可以应用于更多的领域。     

基于ADS1212的高精度数据采集系统及抗混滤波器的设计

介绍了BB公司的ADS1212芯片的功能和性能,解决了他在进行高精度Σ-Δ型A/D转换时的稳压输入问题,详细说明了ADS1212在构成高精度数据采集时的设计方法。然后用Filterlab软件设计了一个五阶低通滤波器,与ADS1212芯片的三阶数字滤波器形成互补,共同滤除进入转换系统的噪声,进而提高数据采集系统的精度。     

ADS1231在桥式传感器数据采集中的应用

介绍TI公司最新推出24位△-∑型模数转换器ADS1231的主要特性。并结合实际应用提出了一种基于ADS1231的高精度电桥式传感器数据采集系统设计方案。该系统采用ADS1231模数转换器和FPGA构成多路数据采集系统,经实测本系统精度能达到21.92位,可应用于高精度的工业采集系统。     

基于ADS7870型数据采集器件的多路数据采集系统串行接口设计

用分立元件实现多路数据采集有很多缺点,针对这一问题,提出一种采用德州仪器公司推出的ADS7870型低功耗数据采集器件组成的多路数据采集系统.介绍该器件的工作原理及应用,给出了ADS7870与微处理器MC68HC11的接口及部分软件程序.该系统可以显著提高多路数据采集的速度和数据转换精度,降低系统功耗.     

基于ADS8343及51单片机的多路采集系统

文中介绍了16位模数转换芯片ADS8343的功能与特性,简述了ADS8343的工作时序,利用C51单片机、RS232串口和计算机系统构成数据采集实时显示系统,并将数据通过上位机软件以文本格式导出,同时给出了ADS8343与51单片机的接口电路和C语言驱动程序。     

ADS1251在高精度数据采集中的应用

ADS1251是TI公司生产的一种高精度、宽动态范围的24位Δ-Σ乏结构的模数转换器。本文介绍了ADS1251的功能特点、内部结构及基本连接电路，给出了ADS1251芯片在高精度数据采集系统中与MCS-51单片机的接口方法及应用程序。     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.