一种用于AMOLED驱动的多模式高效电荷泵

设计了一种用于AMOLED驱动芯片的多模式高效低纹波电荷泵。该电荷泵通过模式选择,使输出电压可配置,实现多模式功能。针对电压建立和模式切换过程中电荷损耗的问题,利用初始化电路和电压检测电路来保证电荷泵中电荷单向传输,同时利用衬底选择开关来解决电荷泵的体效应问题,提高了电压转换效率。采用双边对称的泵电路结构,减小了输出电压纹波。采用UMC 80 nm CMOS工艺进行仿真。结果表明,负载电流为4 mA时,输出电压为8.4~17 V,四种工作模式下电压转换效率均在90%以上,电压纹波均小于1 mV。     

一种宽负载高效率Buck转换器设计

本文提出了一种双模式调制技术,以提高宽负载范围内降压型DC-DC转换器的转换效率。采用自适应导通时间电路(AOT)和斜坡信号V_RAMP产生电路来维持转换器连续导通时间(CCM)工作模式下开关频率基本稳定;利用过零检测电路来检测电感电流,当电感电流过零时,能及时关断续流管,降低开关损耗,进一步提升轻载转换效率。该DC-DC基于SMIC 0.18 um BCD工艺进行电路仿真验证,该电路可在0～3A宽负载范围内正常工作,在输入电压3～5V范围内,PFM模式下输出电压纹波小于5.2mV,1m A负载下转换效率为87.37%。在PWM模式下输出电压纹波小于2.8mV,3A负载下最低转换效率为84.24%。峰值效率可达94.91%,全负载范围内转换效率大于84%。     

用于相变存储器的高效开关电容电荷泵

提出一种应用于相变存储器芯片的新型开关电容电荷泵。对于16 位的相变存储器芯片,系统擦写时间大于100 ns,电荷泵的驱动能力至少为60 mA。相比于传统开关电容电荷泵,该电荷泵根据负载电流大小自动生成一个使能信号,该信号通过控制升压模块功率管的开启与关断来调节输出电压,最终将输出电压控制在一个允许的范围内波动。采用40 nm CMOS工艺对电荷泵进行设计和仿真,结果表明在5 mA负载时,电源效率为87%,输出纹波为2.84 mV;负载电流从0 mA变化到60 mA时,电源效率皆高于82%;负载电流变化在300 mA/μs时,输出瞬态响应时间为1.63 μs,满足相变存储器芯片的使用要求。     

轻载高效Buck转换器设计及其纹波控制方案

提出了一种峰值电流模式PWM下的轻载高效Buck DC-DC控制方案。该方案根据负载大小来自适应调节开关频率和电感电流峰值,实现宽负载范围内高的转换效率和对输出纹波的控制。把误差信号与负载自适应的门限相比较,以判定转换器工作模式。在轻载模式下,通过循环开启或者关闭振荡器来降低转换器的开关频率,降低开关损耗。详细推导了在保持输出电压纹波不变的情况下,负载自适应门限与负载大小之间的关系,并在典型应用下得到二者呈线性关系的结论。采用0.5μm BCD工艺进行仿真,结果显示,在输入电压12 V,输出电压3.3 V下,轻载时最高有94.2%的转换效率,在负载从10 mA到500 mA变化时,轻载模式纹波为120~140 mV,与理论分析的控制纹波130 mV较为符合。     

一种用于H桥功率驱动电路的电荷泵设计

提出了一种可驱动H桥功率电路的电荷泵.为了简化电路设计和确保电路稳定性,本电荷泵采用两倍压电荷泵电路拓扑结构,通过加入两路反馈控制电路来提高电荷泵充电电流和输出电压值的控制精度以及电源转换效率.设计采用0.35μm BCD工艺,通过Cadence Spectre仿真器表明,在负载电流为5mA条件下,电荷泵正常工作时输出电压范围广(10~40V),电源转换效率最高达到91%,输出电压建立所需时间为579μs.样片实测结果显示,在不同输入电压条件下,输出电压纹波控制在385mV以下.     

用于TFT-LCD液晶显示的可调电荷泵设计

为了满足TFT-LCD液晶显示的驱动要求,设计了一种通过控制饱和区MOS管的导通电阻来调节输出电压的可调电荷泵。与传统的电荷泵相比,该电荷泵通过负反馈系统进行控制,具有输出可调、最少外围器件、低纹波、易于集成等优点。采用此可调电荷泵电路的芯片已在UMC0.6μm-BCD工艺线投片,测试结果表明,该可调电荷泵电路工作良好,独特的稳压方式使得电荷泵输出纹波降至最低,并且电荷泵的电容尺寸小,从而减小了整个系统的PCB面积,可调电荷泵正电压输出范围为10～30V,负电压输出范围为-5～-30V,负载电流为50mA时,输出纹波为27mV,可调电荷泵的整体效率可达80%。     

一种高效率升压型ＤＣ－ＤＣ转换器设计

设计了一种基于PWM/PFM调制模式的全负载高效率升压型DC-DC转换器。根据负载不同,实现PWM和PFM模式的自动切换。轻载时,进入PFM模式,降低开关损耗,并加入电感峰值限流,减小输出电压纹波。在DCM状态下,利用休眠模式电路,降低静态功耗,同时提出一种抗振铃电路,进一步提升轻载转换效率。芯片实测结果表明,1mA轻载条件下,效率依然达到91.6%,输出电压纹波约为6.6 mV。全负载最高效率可以达到93.1%。     

采用高性能负压电荷泵的AMOLED驱动DC-DC转换器

提出了一种采用高性能负压电荷泵的有源矩阵有机发光二极管(AMOLED)驱动DC-DC转换器.正输出电压(VOP)由升压转换器(BOOST)和线性稳压器(LDO)级联产生,BOOST中使用前馈方法改善线性瞬态响应,LDO保证了芯片在全负载电流范围内输出电压的纹波.负输出电压(VON)由一种新颖负压电荷泵电路产生,电荷泵仅由MOSFET构成以提高效率.提出了一种新型的转换负压的电平转换电路,降低了开关管导通电阻并提高了负压效率.采用突发(BURST)控制模式提高了轻载效率.芯片采用0.18 μm BCD工艺,其VOP和VON分别为4.6V和-2.4 V,工作频率为1 MHz,正常工作时的负载电流为0～ 50 mA,最大电源效率为89.4％.VOP和VON的纹波均小于7 mV,线性瞬态响应均为5 mV,负载瞬态响应分别为5 mV和20 mV.负输出电压在-0.6～-2.4 V可调,调整步长为0.1V.     

一种单片低功耗电荷泵电源管理电路的设计

基于0.6 μm BiCMOS工艺,设计了一款高精度电荷泵电源管理芯片.该芯片利用2倍压电荷泵电源转换原理,芯片内部集成了具有优异频率响应的振荡器电容,施密特触发器提供内部精准频率,PFM调制提供稳定的输出电压.测试结果表明,芯片输入电压范围为2.7～5.5V,输出电压为5V,电压纹波小于20 mV,内部振荡频率为700 kHz,低功耗模式时电流仅为6.73 μA.     

用于相变存储器的超低输出纹波2X/1.5X电荷泵

本文针对相变存储器编程驱动电路,提出了一种超低输出电压纹波的开关电容型电荷泵。该电荷泵可根据输入电压的不同,自适应工作在2X/1.5X升压模式之间,以获得更高的电源转换效率。相比于传统开关电容型电荷泵,在充电阶段泵电容被充电至预先设定的电压值Vo-VDD(Vo为预期的输出电压);放电阶段,泵电容串联在输入电压VDD与输出端,通过此方法将电荷泵输出端电压稳定在Vo,并有效的降低了由于电荷分享所造成的输出纹波。在中芯国际40nm标准CMOS工艺模型下,对电路进行了仿真验证,结果表明在输入电压为1.6-2.1V,输出2.5V电压,最大负载电流为10mA,输出电压纹波低于4mV,电源效率最高可达91%。     

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.     

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks