一种基于BiCMOS工艺误差放大电路的设计

针对消费电子产品PWM电流型DC-DC电源管理芯片的特点，设计了芯片中所必需的误差放大器，利用带隙基准电压源的原理，结合OTA放大器，提出一种新的误差放大器电路的设计，实现了芯片中误差放大器的功能，满足了芯片电压环路的要求。基于UMC0．6μm BCDBiCMOS工艺，Hspice软件仿真的结果表明所设计的误差放大电路具有结构简单、稳定性高、功耗低等特点，可工作在3．3V-5．5V的电压范围下，性能有很大改善，满足了芯片的需要，可以用于类似芯片中。     

无线传感网射频芯片中4.8GHz低功耗压控振荡器设计

为满足无线传感网射频收发芯片中频率综合器的应用需求,采用TSMC 0.18 μm RF CMOS工艺设计并实现了一个4.8 GHz低功耗LC压控振荡器.电路核心采用电流源偏置的互补差分负阻LC振荡器结构以及3 bit开关电容阵列,输出采用共源级缓冲.给出了电路设计,对噪声抑制进行了分析,并在Cadence环境下完成了版...     

时钟数据恢复电路中的线性相位插值器

针对时钟数据恢复电路(CDR)中相位插值器的非线性使得时钟抖动增大的问题,提出了一种基于非等值电流源阵列的线性相位插值器。根据插值器输出时钟相位与尾电流权重的反函数关系,在传统相位插值器的基础上调整尾电流阵列中每个电流源的设计比例,并将控制管用作共栅管来提高电流源的匹配度和稳定性,从而实现了输出时钟相位与控制信号的线性关系,提高了CDR的调节精度并降低了恢复时钟的抖动。采用0.25μm CMOS工艺设计了一款基于线性相位插值器的CDR。仿真结果表明:传统结构插值器的最大相位误差为63.68%,而所提出的线性相位插值器的最大相位误差仅为9.44%,可有效地降低CDR输出时钟的抖动。     

用于高速PLL的CMOS电荷泵电路

提出了一种应用于高速锁相环中的新型CMOS电荷泵电路．电荷泵核心部分为一带有参考电压电路的双管开关型电路,并对运放构成的反馈回路进行了改进,降低了电荷泵输出电压的抖动．电路采用chartered0．35μm 3．3 V CMOS工艺实现,模拟结果表明电流源输出电压在1～3V区间变化,其输出电流基本无变化,上下电流的失配率小于0．6％,具有很高的匹配性．在3．3V电源电压下,电荷泵输出电压的范围为0～3．1V,具有宽摆幅和低抖动（约0．2mV）等优点,能很好地满足高速锁相环的性能要求．     

采用电荷平衡模数转换器的高精度CMOS温度传感器

针对传统CMOS温度传感器芯片精度低,功耗高和温度范围窄的问题,提出了一种采用电荷平衡模数转换器(ADC)的高精度CMOS温度传感器。为了避免使用高精度带隙基准源,传感器中基于寄生双极晶体管的温度感知电路分别产生与温度成正比和反比的两个电压,再用一个电荷平衡ADC对这两个电压交替量化,得到与实时温度对应的数字量;工艺波动引起的感知误差采用一个外置基准电压来校准;整个温度传感器电路采用0.18μm CMOS工艺设计。仿真结果表明:在-40～125℃的温度范围内,传感器的测量精度可达±0.2℃,完成一次测量的时间仅为42ms,工作电流为130μA,芯片版图面积为0.55mm~2。该温度传感器可应用在植入式医疗、射频标签和物联网等系统中实现对温度的高精度测量。     

一种低功耗时钟芯片的设计

讨论了一种低功耗时钟芯片的设计，从CMOS电路功耗产生原因入手，在振荡分频电路中减小电路工作电压，在时序电路中采用门控技术，达到降低功耗的目的，经流片后测试表明该芯片工作电流0．17mA，满足低功耗要求。     

一种指数曲率补偿CMOS带隙基准源的设计

给出一款带曲率补偿的CMOS带隙基准源电路,该电路利用双极性晶体管电流增益β与温度的指数关系对带隙基准曲率进行补偿,以简单的电路结构获得低的温度系数．电路采用CSMC0．5μm 2P3M mixed signalCMOS工艺设计,Cadence Spectre仿真结果显示,在3．6V的电源电压、-40～85℃范围内,基准源的温度系数为5．0×10-6／℃．     

一种高精度的 CMOS 电流基准

设计了一种高精度的电流基准电路.电路采用正温度系数和负温度系数的电流并联相加,并考虑了电阻的温度系数,得到与温度无关的基准电流源.说明了核电流基准的工作原理,并给出设计公式和误差分析.电路采用0.6 μm CMOS 工艺实现,仿真结果表明,在3 V的电压下,电路的耗电电流为105 μA,在温度-40～120℃范围内,输出电流为5 μA,温度漂移为72 ppm/℃.     

滞环电流控制型大功率LED恒流驱动芯片的设计

基于标准CMOS工艺,采用滞环电流控制模式,设计了一款新型大功率LED恒流驱动芯片。在标准CMOS工艺范围内,芯片能够实现良好的恒流驱动功能。结果表明,电源电压从3到5V变化时,输出电流保持良好的一致性,其最大值和最小值之差仅为0.075mA;随着温度的升高,输出电流先增大后减小,在电路工作的整个温度区间内,输出电流仅仅变化0.165mA;在电感为理想电感情况下,当芯片驱动7个LED灯时,效率最高可达97.8%。     

光发射功率自适控制系统中CMOS低噪声跨阻放大器设计

设计了一种应用于光发射功率自适控制系统中的低噪声宽带跨阻放大器,用0．6μm CMOS工艺实现,在156MHz-3dB带宽范围内最小均方根等效输入噪声电流为130pA／√Hz,在无光状态时电路的总电流为3．3mA,功耗低于国外同类产品。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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