圆形螺旋线圈自感和分布电容的计算

提出了一种计算圆形螺旋线圈自感和分布电容的方法。在元件尺寸小于波长的准静态近似情况下用 Sommerfeld类型积分计算小段平面圆弧的自感和互感 ,然后用螺旋线方程对每一小段圆弧的自感和圆弧间的互感积分 ,算得螺旋线圈的自感。计算螺旋线圈分布电容时同样先计算出两小段同心圆弧间的电容 ,然后用螺旋线方程对其积分算得螺旋线圈的总分布电容。编制了相应的程序对多种情况下的螺旋线圈自感和分布电容进行了计算 ,计算与实验结果比较 ,有较好的一致性。与经验公式相比 ,计算自感的方法有更广的适用范围和对实验结果更好的逼近。而分布电容的计算方法比其它的方法大大减少了运算量。     

The Effect of Mutual Inductance and Mutual Capacitance on the Transient Response of Braided-Shield Coaxial Cables

A quantitative comparison is made of the importance of mutual inductance and mutual capacitance in the leakage of transient signals through the braid of a coaxial cable. The difference between mutual inductance and mutual capacitance coupling is vividly exhibited in the transient predictions. Comparisons of predictions to measurements made on a length of RG-214 test cable are also included.     

互连线串扰耦合噪声的ABCD矩阵模型

高频互连线间的相互耦合和相互感应是产生串扰的一个重要因素。已有文献利用二端口网络ABCD矩阵从理论上求出了耦合互连线阶跃响应,但该方法对互感描述不准确,导致计算复杂,且对串扰耦合噪声的估计不够准确。该文根据互感的基本定义,修改了原模型中互感的表示方法,提出了一个新的ABCD矩阵级联模型,对LTCC工艺互连线的串扰耦合噪声进行分析,并将得到的ABCD模型分析结果与ADS软件的仿真结果对比,验证了改进的ABCD模型的准确性。     

有互感和电源的电容耦合电路的量子涨落

通过正则变换和幺正变换的方法研究了有互感和电源存在的情况下的介观电容耦合电路的量子涨落。结果表明电荷和电流的量子涨落与电源无关。当电路元件确定时，如果L1／L2的值很大或很小，耦合对涨落的影响很大。互感从有到无的过程中，回路1中电流的涨落和回路中2中电荷的涨落有明显的变化。换句话说，互感的有无对涨落的大小起着举足轻重的作用。     

静态场部分电容和互感的测量

多导体部分电容和互感是静态场中非常重要的两个概念.本文介绍了部分电容和互感的特性及测量原理,给出一种测试仪器,通过对具体参数的测试,所得的测试结果与理论计算结果相吻合.实践表明,两个实验系统的开发不仅可以促进学生综合运用所学知识的能力,也可激发学生对电磁场专业理论知识学习的兴趣.     

Parameter extraction and electrical characterization of highdensity connector using time domain measurements

Two coupled connector pins can be represented by an equivalent circuit consisting of six parameters, namely, self capacitance/self inductance per pin, mutual capacitance between pins and mutual inductance between pins. A systematic parameter extraction algorithm has been discussed in this paper using time domain reflectometry (TDR) measurements. This method uses a combination of stand-alone, common mode, and differential mode measurements to extract the connector parasitics. The accuracy of the equivalent circuit has been studied in detail using crosstalk measurements     

有互感的介观电感电容耦合电路的量子效应

利用正则变换和幺正变换的方法研究了有互感的介观电感电容耦合电路的量子效应，并把介观电感电容耦合电路和另外几种耦合电路进行了比较。发现在耦合电容存在的有互感的电路中，通过调节互感耦合系数来控制电路的量子涨落和压缩效应是很方便的。电路中电荷和电流的不确定关系与正则变换参数ψ和不确定关系参数ξ有关。当ξ→1或ψ→nπ／2(n=0，1，2，…)时，电荷和电流的不确定关系接近最小值h／2。     

浅谈电气测量抗干扰技术的教学

针对"电气测量技术"教学中抗干扰技术方面普遍存在的不足,本文归纳出电气测量中典型的干扰源,并用分布电容和空间互感来阐明干扰耦合的机理。据此分析总结出电气测量系统在设计布局中减小电容耦合和互感耦合的方法,以及在实际测量中常使用的抗干扰技术,可供讲授"电气测量技术"的教师参考借鉴。     

FEXT-eliminated stub-alternated microstrip line for multi-gigabit/second parallel links

A stub-alternated microstrip line is proposed for multi-gigabit/second parallel links on a PCB. Without guard traces, the uniformly distributed stub structure eliminates the far-end crosstalk and crosstalk-induced jitter by increasing the mutual capacitance with little change in the mutual inductance. Coupling characteristics were measured and fitted with an empirical equation.     

Shielding Effectiveness of Braided-Wire Shields

An analysis of the shielding effectiveness of braidedwire shields is made using the parameters of the woven wire and the theory of electromagnetic coupling through small irises. The coupling through the rhombic-shaped holes in the braid is approximated by using the electric and magnetic polarizabilities of elliptical holes of the same width and length as the rhombus. The analysis develops the transfer impedance and the mutual capacitance of the shield. The transfer impedance is calculated and plotted for shields of different optical coverages. The variation of mutual capacitance and mutual inductance with the weave angle of the braid are examined.     

Validation and test issues related to noise induced by parasitic inductances of VLSI interconnects

Shows the results of studies of noise induced by various combinations of parasitic capacitances and inductances. Interconnects are simulated with parameters obtained from a 0.18 /spl mu/m process. The four kinds of noise addressed are (i) crosstalk pulse; (ii) crosstalk speedup and slowdown; (iii) oscillatory noise; (iv) combination of oscillatory noise and crosstalk pulse. The crosstalk effects induced by a combination of mutual capacitance and mutual inductance can be larger than those induced by mutual capacitance alone, even if capacitive crosstalk dominates. For certain interconnects that are capacitively and inductively coupled, transitions in the same direction on an aggressor and victim line can cause speedup or slowdown, depending on timing parameters. A similar observation holds for transitions in opposite directions. We also observe that oscillatory noise can combine with crosstalk pulse under certain skew conditions and give rise to a large magnitude of noise. We show that inductance induced noise can be a problem in medium length interconnects. Because such interconnects can occur in combinational logic blocks, the generation of suitable vectors for test and validation of such logic blocks is of concern.     

Realization of new mutually coupled circuits using mutators

A method for realizing new mutually coupled circuits by using mutators is described. Various types of mutually coupled circuits, such as a mutual inductance, a mutual frequency-dependent negative resistance, and a frequency-dependent negative inductance, are realized by connecting a network between two mutators which have the suitable transmission matrix. New mutually coupled circuits composed of three impedances of different kinds, that is, two self-impedances and one mutually impedance, are also described. The theoretical frequency responses of the transfer functions of coupled tuned circuits composed of these mutually coupled circuits are shown, and experimental results of a coupled tuned circuit using mutual inductance are shown.     

Unified AC model for the resonant tunneling diode

A physics-based model is shown to yield the small-signal equivalent circuit of the resonant tunneling diode (RTD) including an analytic expression for both the quantum inductance and capacitance. This model unifies previous models by Brown et al. for quantum inductance and by Lake and Yang for quantum capacitance, and extends the RTD SPICE model of Broekaert. The equivalent circuit has been fit to both current-voltage and microwave S-parameter measurements of AlAs-InGaAs-InAs-InGaAs-AlAs RTDs from 45 MHz to 30 GHz and over biases from 0 to 0.81 V. Good agreement between the model and measurement is shown.     

Over GHz electrical circuit model of a high-density multiple line grid array (MLGA) interposer

The multiple line grid array (MLGA) interposer was recently introduced as a future high-density high-speed bonding method. In this paper, we introduce an electrical model and high-frequency characteristics of the MLGA interposer. The high-frequency electrical model was extracted from microwave S-parameter measurements up to 20 GHz as well as from fundamental microwave network analysis. For the parameter fitting process during model extraction, an optimization method was used. Several different types of MLGA interposers were designed, assembled and tested. The test vehicles contained coplanar waveguides, probing pads and an MLGA interposer structure. The height of the MLGA, the conductor shape inside the MLGA, and the dielectric insulator of the MLGA were varied. From the model, an MLGA with a height of 0.4 mm and a polymer dielectric insulator was found to have 203 pH of self inductance, 49 pH of mutual inductance with the nearest ground conductor line, and 186 fF of mutual capacitance. By reducing the height of the MLGA and by using an insulator with a lower dielectric constant, parasitic inductance and capacitance is further reduced. TDR/TDT simulation and measurement showed the validity of the extracted model parameters of the MLGA interposer. Circuit simulation based on the extracted model revealed that the MLGA interposer could be successfully used for microwave device packages up to 20 GHz and for high-speed digital device packages with a clock cycle up to 5 GHz.     

Inductance model and analysis methodology for high-speed on-chip interconnect

With operating frequencies entering the multi-gigahertz range, inductance has become an important consideration in the design and analysis of on-chip interconnects. In this paper, we present an accurate and efficient inductance modeling and analysis methodology for high-performance interconnect. We determine the critical elements for a PEEC based model by analyzing the current flow in the power grid and signal interconnect. The proposed model includes distributed interconnect resistance, inductance and capacitance, device decoupling capacitances, quiescent switching currents in the grid, pad connections, and pad/package inductance. We propose an efficient methodology for extracting these elements, using statistical models for on-chip decoupling capacitance and switching currents. Simulation results show the importance of various elements for accurate inductance analysis. We also demonstrate the accuracy of the proposed model compared to the traditional loop-based inductance approach. Since the proposed model can consist of hundreds of thousands of RLC elements, and a fully dense mutual inductance matrix, we propose a number of acceleration techniques that enable efficient analysis of large interconnect structures.     

渐变悬浮电感参数化模型的仿真设计分析

针对目前片上电感无法同时提高品质因数和电感值的问题,设计了渐变悬浮电感参数化模型,研究了金属线宽及线圈间距的变化对电感性能的影响。进一步将其与双层电感模型相结合,利用HFSS软件仿真分析得到,双层渐变悬浮电感可兼顾磁场损耗、寄生电容、线圈互感等因素,同时大幅度提高品质因数和电感值,品质因数、电感值分别可达24. 66,118n H,较传统单层悬浮电感分别提高48%,436%。结果还表明上层线圈逆时针旋转0. 4°,其品质因数可提高4. 11%。     

关于谐振电路中能量问题的讨论

在谐振电路中,一般学生会认为电源所提供的能量全部被电阻所吸收,能量的互换只是发生在电感和电容之间.本文以RL与C并联谐振电路为例,给出了电路谐振时电感和电容中所储存的总能量随时间的变化规律,其电感和电容所储存的总能量并不是恒定值,因此认为谐振电路中,能量的互换只是发生在电感和电容之间的观念是错误的.     

Voltage Regulator Optimization Using Multiwinding Coupled Inductors and Extended Duty Ratio Mechanisms

This paper examines design optimization of voltage regulators (VRs) for microprocessor applications. Optimality of competing VR topologies, such as conventional (Conv) buck, coupled inductor, and extended duty ratio converters, is examined using efficiency norms and a new cost-per-watt metric to compare the amount of output capacitance (which is strongly correlated to the VR cost) to the efficiency. Coupled inductors provide a higher steady-state inductance than transient inductance. Lower transient inductance allows for smaller output capacitance. However, lower output capacitance requires a higher switching frequency and thus yields greater switching losses and lower efficiency. Extended duty ratio mechanisms reduce the switching voltage, and hence, reduce switching losses and increase efficiency. Experimental data are provided that the coupled inductor extended duty ratio converter has the same average efficiency, has higher light-load efficiency, and uses one-third of the output capacitance as the Conv multiphase buck converter. Hence, the combination of multiwinding coupled inductors and extended duty ratio mechanisms is shown to be the optimal VR configuration. The optimality concepts contributed in this paper resolve the ambiguity between VR cost and efficiency, and are essential for selecting the best solution among several competing VR designs.      

Traces in proximity to gaps in return planes

Coupling between circuitry on printed circuit boards can be mitigated by a variety of well-known techniques. One such technique is to isolate circuitry in different areas of the printed circuit board by strategically placing a gap in the signal return plane. However, this technique is only effective at reducing common-impedance coupling, which is generally not a significant coupling mechanism at frequencies above 1 MHz. This paper investigates the effect of a gap located between and parallel to adjacent microstrip traces. The effect of the gap on the mutual inductance and mutual capacitance is evaluated. Laboratory measurements and numerical simulations show that gaps in the return plane are ineffective at reducing inductive and capacitive crosstalk in most configurations, and in some cases they increase the mutual coupling between printed circuit board traces.     

基于柔性衬底的平面螺旋电感的计算与仿真

提出了一种基于柔性衬底的平面螺旋电感,介绍了柔性衬底的优点,对比了平面电感的结构类型,给出了平面螺旋电感的自感、电容、串联电阻及互感的计算方法,并对方形平面电感进行了仿真.