基于74HC4046AD的感应加热电源设计

针对感应加热过程中,铁质负载的电阻率和磁导率会发生变化,使谐振频率发生变化的情况,文中介绍了一种锁相驱动方案。该方案可以实现负载频率自动跟踪,它的电路包括锁相环电路、同步信号提取电路和隔离驱动电路三部分。其中锁相电路实现负载频率的跟踪,同步信号提取电路和隔离驱动电路实现IGBT驱动。设计并制作一台2.5 kW/20 kHz感应加热电源样机,通过给注塑机炮筒加热,实验数据表明锁相驱动方案锁相稳定。     

基于Pcap01的MEMS电容压力传感器测量电路设计

基于TDC原理文中提出了一种用于MEMS电容式压力传感器的微弱电容测量电路。该电路以微处理器STM32F103为控制核心,通过SPI总线对Pcap01芯片进行时序控制,完成电容数据的采集、分析、处理和显示。该电路具有体积小、抗干扰性强、分辨率高和刷新频率高的特点。通过对10 pF以下的固定电容和MEMS电容式压力传感器测量验证新电路的性能。实验结果表明,电路在10 Hz刷新频率下有效精度位为16位,分辨率可达61 aF。     

一种CCD彩色摄像系统的视频锁相同步系统

介绍一种应用于ＣＣＤ彩色摄像系统的视频锁相同步系统。基于锁相理论的视频锁相同步系统是一个二级锁相环路,包括同步信号发生电路和高频点像素时钟电路。并详细阐述了同步信号发生电路和高频点像素时钟电路的锁相原理及电路。高频点像 时钟电路的外分频电路是由现场可编门阵列实例可编程特必珂得到不同频率的高频点像素时钟。     

一种低功耗快速锁定简易锁相式频率合成器

采用0.5 μm CMOS工艺,设计了一种简易锁相式频率合成器。采用“类锁相环”结构,在传统锁相环频率合成器的基础上,去除了电荷泵和低通滤波器。利用鉴频鉴相器的输出结果作为开关信号,控制压控振荡器的工作状态,使压控振荡器的输出信号在第N个周期返回鉴频鉴相器后立即被关断,直到下一个参考时钟周期来临。分析了电路的结构和工作原理,并对每个模块进行了理论分析。该频率合成器能够快速地产生固定的时钟频率,具有结构简单、功耗低、锁定时间短等优点。仿真结果表明,输入参考时钟为4 MHz时,该频率合成器的输出频率为15.96 MHz,功耗为2.96 mW,锁定时间小于1 μs。     

CRT显示器控制参数自动调节电路

新型显示器不仅屏幕尺寸扩大了、分辨率提高了,而且各项参数均能在分辨率重新设置后自行调节,有极佳的易用性。本文介绍多频显示器控制参数的自动调节电路。自动调节的一般方法多频同步显示器能够自动适应显示模式的变化,捕捉同步信号,实现行、场扫描的同步而不致于发生显示混乱的情况,同时又能在信号频率变化时自动调节行、场电路的工作状态,使画面的幅度(行幅和场幅)不发生明显的变化。具体表现在下述几个方面:1. 控制行、场振荡器的振荡频率,迫使行、场振荡频率和相位与外部输入的行同步信号同步;2. 作为场幅控制信号,控制场扫描电路场幅…     

LG高档商用液晶显示器

885LE和870LE是LG公司新推出的两款高档商用18英寸平面液品显示器。885LE的特性包括：在0.28毫米点距下,可在85Hz刷新频率下达到1280X1024的分辨率,显示的色彩达到了1670万种,显示亮度达到典型状况下的每平方米180流明,而其典型的对比度是200：1,其最大响应时间达到了50毫秒,其中上升响应时间为20毫秒,下降响应时间为30毫秒;在可视角度方面,LG885LE水平和垂直视角均达到了180度,几乎没有视野死角。885LE采用了DVI数字接口。与885LE相比,870LE的分辨率在0.28毫米点距支持下,也达到了85Hz刷新频率下的1280X1024,870LE…     

高分辨率彩色LCoS头盔显示器电路系统的设计与实现

介绍了分辨率为1024×768,子场刷新频率为180Hz的硅基液晶(LCoS)彩色头盔显示器电路的总体设计,并详细阐述了其中关键模块的设计与实现.使用高速SDRAM替换SRAM作为帧存储器,为高分辨率显示提供了足够的容量和带宽;借助基于FPGA的高速低压差分信号(LVDS)数据传输成功实现了系统的模块化设计,有效地减轻了头盔显示器的重量,将放人头盔的PCB面积减少到46 mm×56 mm.经对样机进行测试,结果表明,系统工作稳定可靠,能够实现高分辨率彩色图像的实时显示,而且图像清晰.     

硅基OLED微显示的数模融合驱动电路设计

当前,硅基OLED(organic light-emitting diode,OLED)微显示器正向高分辨率、高刷新频率方向发展。为了实现像素面积微小型化、降低扫描数据流量从而更好满足高分辨率、高刷新率的要求,提出了一种新型的有源矩阵硅基微显示驱动电路结构。该电路采用数模融合的扫描策略,该策略结合了数字脉宽调制方式和模拟幅值调制方式;设计了多列像素复用列驱动通道的结构,满足数模融合扫描方式的时序要求。最后通过对列驱动单元后仿真,得到关键时序参数,结合数模融合扫描策略确定了几个具体结构方案。在保证红绿蓝三色像素尺寸在10μm以下的情况下,与单纯的数字扫描策略相比,每秒数据流量降低了25%~64%。结果表明:基于数模融合扫描策略的硅基OLED微显示驱动电路在保证像素面积微小型化基础上,降低了扫描数据流量,有利于高分辨率高刷新率的显示。     

利用可编程的扭斜控制解决时钟网络问题的方法

时钟网络管理问题提高同步设计整体性能的关键是提高时钟网络的频率。然而,诸如时序裕量、信号完整性、相关时钟边沿的同步等因素极大地增加了时钟网络设计的复杂度。传统时钟网络的设计采用简单的元件,诸如扇出缓冲器、时钟发生器、延时线、零延时缓冲器和频率合成器。由于PCB     

基于SRAM的光栅光调制器的控制扫描电路研究

提出一种基于静态随机存储器（SRAM）的光栅光调制器的控制扫描电路。介绍了光栅光调制器的加工工艺和工作原理,分析了该控制扫描电路的原理和技术指标。利用Cadence软件和无锡华润上华0.5μm工艺,设计和加工了大小为8×8的控制扫描电路。通过实验表明：加工的SRAM有源矩阵单元能够实现对输出电压的更新或保持;且加工的控制扫描电路能够实现对光栅光调制器阵列的有源控制,从逻辑功能上验证了该控制扫描电路设计的正确性。结果表明：只要该控制扫描电路的行、列驱动电路能够在248MHz的时钟频率下工作,且有源矩阵单元的开关时间小于121ns,则该控制扫描电路可以满足光栅光调制器用于分辨率为1920×1080,帧频为30Hz,灰度级为256的投影显示。     

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.