Circuit Analysis Techniques Research Articles

Optimizing scrubbing by netlist analysis for FPGA configuration bit classification and floorplanning

Existing scrubbing techniques for SEU mitigation on FPGAs do not guarantee an error-free operation after SEU recovering if the affected configuration bits do belong to feedback loops of the implemented circuits. In this paper, we a) provide a netlist-based circuit analysis technique to distinguish so-called critical configuration bits from essential bits in order to identify configuration bits which will need also state-restoring actions after a recovered SEU and which not. Furthermore, b) an alternative classification approach using fault injection is developed in order to compare both classification techniques. Moreover, c) we will propose a floorplanning approach for reducing the effective number of scrubbed frames and d), experimental results will give evidence that our optimization methodology not only allows to detect errors earlier but also to minimize the Mean-Time-To-Repair (MTTR) of a circuit considerably. In particular, we show that by using our approach, the MTTR for datapath-intensive circuits can be reduced by up to 48.5% in comparison to standard approaches.

Computing an expected hitting time for the 3-urn Ehrenfest model via electric networks

We study a three-urn version of the Ehrenfest model. This model can be viewed as a simple random walk on the graph represented by Z3M, the M-fold direct product of the cyclic group Z3 of order 3, where M is the total number of balls distributed in the three urns. We build an electric network by placing a unit resistance on each edge of the graph. We then apply a series of circuit analysis techniques, including the series and parallel circuit laws and the Delta-Y transformation, to establish shorted triangular resistor networks. A recurrence relation is derived for the effective resistance between two corner vertices of the triangular resistor networks. The recurrence relation is then used to obtain an explicit formula for the expected hitting time between two extreme states where all balls reside in one of the three urns.

A New Methodology for Circuit Analysis with Reverse Analysis Capability

This paper presents a novel technique for the analysis of looped linear time-invariant electric circuits. This approach works in both time and Laplace domains; any type of elements could hence be incorporated. The circuit elements are partitioned into twofold classes of basic circuit and subsidiaries. The basic circuit is a spanning tree of the network, and the subsidiaries include circuit elements hypothetically removed from the looped electric circuit to open the loops. The subsidiaries include a suit of passive elements which might not even make any interconnected circuit. The circuit governing equations of flow and energy conservation are manipulated so that branch currents in the subsidiaries and branch voltages in the basic circuit are considered as independent variables to calculate passive element properties (impedance of all passive elements) directly. In contrast to existing methods, this technique is tailored for the circuit analysis in a reverse manner. As a complement for conventional circuit analysis techniques, this method can be taught in the undergraduate program to offer the students an alternative tool for the circuit analysis.

Evaluation of an Early Three Phase Approach to Electric Circuit Instruction

This paper presents a novel approach to the study of electric circuits: utilizing three phase electric power systems to introduce students to the techniques of circuit analysis beyond Kirchhoff’s and Ohm’s Laws. The efficacy of the pedagogy is evaluated by comparison of student performance on DC circuits assessment quiz pre and post intervention and by comparison to circuit analysis methods used by experts. Also discusses is how the curriculum effects students qualitative and quantitative conceptions of the behavior of voltage and current in DC resistive circuits.

A Systematic Study of ESD Protection Co-Design With High-Speed and High-Frequency ICs in 28 nm CMOS

This paper discusses a systematic study of electrostatic discharge (ESD) protection circuit co-design and analysis technique for high-frequency and high-speed ICs in 28 nm CMOS. The comprehensive ESD-IC co-design flow includes ESD device optimization and characterization, ESD behavioral modeling, backend interconnect characterization, parasitic ESD parameter extraction, ESD failure analysis and ESD co-design evaluation for ICs operating at up to 15 GHz and 40 Gbps. Ring oscillator, dummy I/O buffer and current mode logic (CML) circuits were used to demonstrate the co-design method. This practical ESD-IC co-design technique can be applied to high-performance, high-frequency and high-speed ICs.

M , the conservative power quantity based on the flow of energy

The reactive power in non-sinusoidal circuits is determined here from an energy analysis instead of using the non-sinusoidal apparent power S. In the first of the two energy analyses, circuits previously examined by the currents’ physical components power theory are re-examined using the principle of conservation of energy, the balance principle of the reactive power and the concept of reactive power compensation. This energy analysis yields a reactive power value substantiated by the aforementioned principles and power theory but it also suggests a value of S that differs from its traditional definition. The energy analysis performed with the circuit analysis technique based on geometric algebra, its GN domain power theory and M , a conservative power quantity based on the flow of energy, confirms the reactive power value attained in the former analysis. More importantly, M clarifies three intriguing issues about S: its value, its physical significance and whether this quantity can lead to erroneous conclusions. These, and previous results, demonstrate that the reactive power should be assessed on the energy flow but a multidimensional mathematical framework is needed to better understand energy flow in non-sinusoidal circuits.

Electric Circuit Analysis Using a Simple Assumption- Based Technique

This paper demonstrates a simple technique to analyze linear electric circuits. The technique is based on assuming some voltage or current values according to the given resistance/impedance values such that a relative circuit performance is obtained. The actual circuit results are achieved directly by normalizing the assumed values using a specific formula. In practice, this method either reduces the number of simultaneous equations or simplifies the mathematical formulas; hence the overall analysis procedure is reasonably accelerated. It is highly recommended that this method is taught in electric circuit courses especially in the beginning chapters so that students can have more variety of circuit analysis techniques. It is also possible to apply such a method to verify an existing solution or vice versa.

Active vibration control using mechanical and electrical analogies

Mechanical-electrical analogous circuit models are widely used in electromechanical system design as they represent the function of a coupled electrical and mechanical system using an equivalent electrical system. This research uses electrical circuits to establish a discussion of simple active vibration control principles using two scenarios: an active vibration isolation system and an active dynamic vibration absorber (DVA) using a voice coil motor (VCM) actuator. Active control laws such as gain scheduling are intuitively explained using circuit analysis techniques. Active vibration control approaches are typically constraint by electrical power requirements. The electrical analogous is a fast approach for specifying power requirements on the experimental test platform which is based on a vibration shaker that provides the based excitation required for the single Degree- of-Freedom (1DoF) vibration model under study.

Nonlinear circuit analysis technique for microelectromechanical systems with a time‐variant capacitor and an AC power source

Microelectromechanical systems (MEMS) utilise time-variant capacitors as transducers in many applications. However, this kind of component can introduce harmonics and disturbances into the circuit with an AC power source, which is difficult to evaluate through closed-form solutions. This Letter proposes an iterative solution to analyse the dynamics of MEMS devices which contain a time-variant capacitor and an AC source. First, the expressions of the time-variant capacitor, AC source and their derivatives with respect to time are determined. Then, an initial solution that is sufficiently close to the actual solution is determined using linear circuit analysis. On the basis of the previous steps and the principles of the iterative method, an approximated solution combining the initial solution and its iteratively-derived higher-order terms is reached. Adding additional higher-order terms can improve the accuracy of the solution. A case study considering a MEMS device which has an AC power source and sinusoidal motion was performed using MATLAB Simulink. The simulation study further demonstrated that: (i) this iterative solution can effectively analyse the dynamics of MEMS devices with a time-variant capacitor and an AC power source; and (ii) computing additional higher-order terms derived from the initial solution can further improve the solution's accuracy.

Simplified analog CMOS mid-band small-signal analysis utilizing short-circuits and incremental perturbations

This article simplifies several small-signal CMOS circuit analysis techniques from their existing forms in textbook approaches. Several CMOS loads and circuit topologies are analyzed through a simplified “incremental perturbation” approach, and solutions can sometimes be found almost by “common-sense” inspection with some use of Norton’s and Thevenin’s transformations. In many cases there is no need to write and solve multiple equations, but just the utilization of “incremental KVL or incremental KCL.” Elimination, reduction, merger or conversion of dependent current sources through “opportunistic short circuits” is a central idea behind this methodology.

Mesh analysis for extracting the S-parameters of lumped element RF and microwave circuits

This paper demonstrates the applicability of basic mesh current circuit analysis techniques, usually learned in the first year of engineering studies, to lumped element RF circuits, which are usually taught with more sophisticated analysis techniques. As an example, the S-parameters of the 90° lumped element hybrid coupler is derived using the traditional mesh current analysis, and compared to that of the distributed micro-strip response. The distributed transmission line coupler is transformed into equivalent lumped element PI sections, and then combined for the resulting lumped element coupler. Mesh current analysis is then utilized to demonstrate the equivalence between the lumped element coupler and the micro-strip coupler as well as the ability to easily simulate the effects of finite inductor Q on the circuit's performance.

Introducing Creativity In A Design Laboratory For A Freshman Level Electrical And Computer Engineering Course

In the electrical and computer engineering (ECE) curriculum at The University of Alabama, freshmen are introduced to fundamental electrical concepts and units, DC circuit analysis techniques, operational amplifiers, circuit simulation, design, and professional ethics. The two credit course has both lecture and laboratory components that address these topics. The laboratory has been used, in this project, to provide students an experience in design. In one of the laboratory assignments, students work in teams to design and build products giving attention to both function and aesthetics. Creativity is an important attribute for engineers practicing their profession in a global society. The creative process was exercised in the design lab by progressively engaging students through various stages including: brainstorming, formation of a construction plan, producing schematic representations, and implementing their design. In a two- year period, four laboratory exercises were developed to provide design experiences in our introductory ECE course. Assessment results show that the majority of students enjoy several aspects of the laboratory on design and creativity. At the same time, they consider this lab to be one of the most difficult ones due to its open-ended nature. Students who experienced the creative lab were somewhat more likely to state they would continue in their major. Overall, the project team concluded that the creative lab was valuable and did raise awareness of the creative process.

Using Classic Circuit Analysis Methods to Describe Voltage Performance of Battery-Ultracapacitor Power Source

Circuit analysis methods taught in principles of engineering courses were used to develop instructional material for inclusion in teaching a course on Energy Systems Projects. The course involves lectures and lab experiments on renewable energy sources. The paper describes an experiment and its analysis as a typical unit in the course. The experiment concerned measuring the supply voltage of a rechargeable battery-ultracapacitor power source. Transformations were used in the analysis to reduce the battery-ultracapacitor circuit to a single loop and the Laplace transform technique was then applied to derive equations describing the transient voltage of the battery-ultracapacitor circuit discharging through a resistive load. The equations were used for calculations and measurements for a sealed D size lead acid battery in parallel with an ultracapacitor. Teaching the course in experiments and related lectures in a laboratory setting enhanced the excitement factor in both the teaching and learning of circuit analysis techniques.

Interacting plasmonic nanostructures beyond the quasi-static limit: a “circuit” model

The interaction between individual plasmonic nanoparticles plays a crucial role in tuning and shaping the surface plasmon resonances of a composite structure. Here, we demonstrate that the detailed character of the coupling between plasmonic structures can be captured by a modified "circuit" model. This approach is generally applicable and, as an example here, is applied to a dolmen-like nanostructure consisting of a vertically placed gold monomer slab and two horizontally placed dimer slabs. By utilizing the full-wave eigenmode expansion method (EEM), we extract the eigenmodes and eigenvalues for these constituting elements and reduce their electromagnetic interaction to the structures' mode interactions. Using the reaction concept, we further summarize the mode interactions within a "coupling" matrix. When the driving voltage source imposed by the incident light is identified, an equivalent circuit model can be constructed. Within this model, hybridization of the plasmonic modes in the constituting nanostructure elements is discussed. The proposed circuit model allows the reuse of powerful circuit analysis techniques in the context of plasmonic structures. As an example, we derive an equivalent of Thévenin's theorem in circuit theory for nanostructures. Applying the equivalent Thévenin's theorem, the well-known Fano resonance is easily explained.

Analysis of Switching Circuits Through Incorporation of a Generalized Diode Reverse Recovery Model Into State Plane Analysis

A new switching circuit analysis technique is proposed in which the reverse recovery and junction capacitance non-idealities of diode-based switches are incorporated into a state plane analysis of the circuit. Accurate state plane modeling of the reverse recovery process is based on the development of new generalizations of the classic charge control model. Using as an example a zero-voltage switching dc transformer possessing high sensitivity to diode characteristics, these generalizations are shown to be necessary to achieve accurate results across all operating modes. The proposed circuit analysis technique produces excellent modeling agreement with results measured on a hardware prototype of the dc transformer circuit.

The IEEE Standard 1459, the CPC Power Theory, and Geometric Algebra in Circuits With Nonsinusoidal Sources and Linear Loads

An alternative circuit analysis technique and its associated power theory is compared to the IEEE Standard 1459 and the current's physical components power theory. The comparison shows that elimination of the fundamental reactive power quantity Q1 as defined by the Standard does not ensure supply current reduction. In contrast elimination of the reactive current as defined by the CPC power theory ensures supply current reduction. However, the balance principle of the reactive power cannot be applied to the CPC power theory as the definition of the reactive power is not a signed quantity. The alternative method which uses geometric algebra instead of complex numbers, multivectors in place of phasors and the Euclidian N-dimensional space instead of the frequency domain succeeds in defining a decomposition that accounts for the total nonactive power, and also satisfies conservation. The alternative circuit analysis technique allows viewing the flow of currents and energy/powers in the circuits under examination. Additionally, the paper provides 4 reasons why the present definition of apparent power defined as the product of the magnitude of current and voltage is unsuitable for nonsinusoidal circuits in the GN domain.

A Method for Balancing a Single-Phase Loaded Three-Phase Induction Generator

When a three-phase induction generator (IG) supplies unbalanced loads, its terminal voltages and line currents are also unbalanced, which may cause the IG to overheat and need to be derated. A single-phase loaded self-excited induction generator (SEIG) works under most unfavorable load unbalance conditions. This paper proposes a three-capacitor circuit scheme and a method to find the values of the self-excitation capacitors that allow the SEIG to be balanced. The SEIG is modeled by a two-port network equivalent circuit that resolves the SEIG into its positive- and negative-sequence circuits associated with the self-excitation capacitors and the load. The network can then be analyzed by common AC circuit analysis techniques. Successful results for balancing the SEIG supplying a single-phase load have been achieved by properly choosing the values of the excitation capacitors. The proposed method has also been validated by experiments on a 0.37 kW SEIG.

Advantages of Geometric Algebra Over Complex Numbers in the Analysis of Networks With Nonsinusoidal Sources and Linear Loads

An alternative circuit analysis technique is used to study networks with nonsinusoidal sources and linear loads. In contrast to the technique developed by Steinmetz, this method is supported by geometric algebra instead of the algebra of complex numbers, uses multivectors in place of phasors and is performed in the GN domain instead of the frequency domain. The advantages of this method over the present technique involve: determining the flow of current and power quantities in the circuit, validating the results using the principle of conservation of energy, discerning and revealing other forms of reactive power generation, and the ability to design compensators with great flexibility. The power equation is composed of the active power and the CN -power representing the nonactive power. All the CN-power terms are sorted into reactive power terms due to phase shift, reactive power terms due to harmonic interactions and degrading power terms which determine the new quantity called degrading power. This decomposition shows that estimating these quantities is intricate. It also displays the power equation's functionality for power factor improvement. The geometric addition of power quantities is not pre-established but results from applying the established norm and yields the new quantity called net apparent power.

Safety Analysis for Complex Thermal System Based on Sneak Path Technique

Sneak circuit analysis technique is an important analytical tool that can promote the safety and reliability of the circuit control system. It applied to aerospace control engineering widely now. Comparing a thermal system and electric circuit system, the concept and method of sneak path analysis for complex thermal system are proposed by this paper. And the development and application vista of thermal system sneak path analysis and specific implementation are analysed.

Simulation on S Parameter of an X-Band Wilkinson Power Divider

This paper describes analysis of the S parameter of an X-band (8-12GHz) Wilkinson power divider by using odd-even mode, as well as full circuit analysis technique. The closed-form model of the S parameters versus normalized frequency response of the power divider is proposed for the first time according to our acknowledgement. The expressions are compared with the results obtained from a full-wave electromagnetic simulator (ADS) and found to yield acceptable agreement: the insertion loss is -3dB, the maximum difference of return loss of port 1 and isolation is about 0.17dB, the return loss of port 2 is less than -38dB.