Simulation Program With Integrated Circuit Emphasis Simulation Research Articles

2-D SPICE Simulation and Analytical Calculation of Spreading Resistance Effects in Emitter Wrap-Through Cells With Nonsquare Via-Hole Pattern

Cell concepts that feature via-holes, like the emitter wrap-through concept, suffer from higher series resistance losses than conventional solar cells. A part of these resistance losses is due to the fact that a small size element, in this case a via-hole, has to collect the current of a wide area on the front side, which leads to the so-called spreading resistance. An analytical equation already exists which describes the spreading resistance effects that are present in these cells. This equation is an accurate description for a quadratic or hexagonal pattern of via-holes. For cells that feature an interdigitated metallization grid on the rear side, like emitter wrap-through solar cells, the arrangement is often nonsquare because the distance between two via-holes is different in the x- and y-directions. In this paper, it is shown that the existing formula is in excellent correlation with the results from simulation program with integrated circuit emphasis (SPICE) simulation if a quadratic symmetry element is chosen. The SPICE simulation is then adjusted for nonsquare symmetry elements, showing that the existing formula is not valid for these arrangements and has to be modified. The derived analytical modification is adapted to yield a better description of the spreading resistance in the emitter of such a cell structure for variable via-hole distances in the x- and y-directions. The relative deviation between the simulation results and the analytic approach is less than 15%. This enables an accurate calculation of the resistance losses of relevant technological configurations.

Modeling of Electromagnetic Interference and PLC Transmission for Loads Shedding in a Microgrid

This paper presents an electric line study of microgrid. To optimize the management of electric sources, generally a proposed solution is the load shedding. To achieve it, the power line communication (PLC) is often used to communicate when it is not possible to add cables. Such technologies use the power line network as a propagation and communication medium. The network quality depends mainly on the power grid topology, but also on the connected household electrical appliances that have a large impact on the PLC systems due to their impedances and noise. In this paper, we propose a new simulation program with integrated circuit emphasis (SPICE) approach for modeling both the electromagnetic (EM) disturbances generated by a printer and the power network. First, the high-frequency power cable characteristics are extracted from S parameter measurements. Then, the model of EM noise generated by a printer is deduced from time-domain measurement and integrated to the SPICE simulator by means of its Laplace transform. Simulation and modeling results of a simple power grid are given in terms of insertion loss evaluation (S21 parameter). A validation of the EM noise model is performed by means of a comparison between simulation and measurement results in frequency domain at several points of a simple power network. The present approach allows the prediction of EM interference generated by all household devices at any access points of a power line network without carrying out a systematic measurement.

SPICE modelling of magnetic tunnel junctions written by spin-transfer torque

Spintronics aims at extending the possibility of conventional electronics by using not only the charge of the electron but also its spin. The resulting spintronic devices, combining the front-end complementary metal oxide semiconductor technology of electronics with a magnetic back-end technology, employ magnetic tunnel junctions (MTJs) as core elements. With the intent of simulating a circuit without fabricating it first, a reliable MTJ electrical model which is applicable to the standard SPICE (Simulation Program with Integrated Circuit Emphasis) simulator is required. Since such a model was lacking so far, we present a MTJ SPICE model whose magnetic state is written by using the spin-transfer torque effect. This model has been developed in the C language and validated on the Cadence Virtuoso Platform with a Spectre simulator. Its operation is similar to that of the standard BSIM (Berkeley Short-channel IGFET Model) SPICE model of the MOS transistor and fully compatible with the SPICE electrical simulator. The simulation results obtained using this model have been found in good accord with those theoretical macrospin calculations and results.

SRAM Circuit-Failure Modeling and Reliability Simulation With SPICE

Based on some new accelerated lifetime models and failure equivalent circuit modeling techniques for the common semiconductor wear out mechanisms, simulation program with integrated circuit emphasis (SPICE) can be used to characterize CMOS VLSI circuit failure behaviors and perform reliability simulation. This paper used a simple SRAM circuit as an example to demonstrate how to apply SPICE to circuit reliability modeling, simulation, analysis, and design. The SRAM circuit, implemented with a commercial 0.25-mum technology, consists of functional blocks of 1-bit six-transistor cell, precharge, read/write control, and sense amplifier. The SRAM operation sequence of "write 0, read 0, write 1, read 1" was first simulated in SPICE to obtain the terminal voltage and current stress profiles of each transistor. Then, normalized lifetimes of all transistors in terms of each failure mechanism were calculated with the corresponding accelerated lifetime models. These lifetime values were sorted to single out the most damaged transistors. Finally, the selected transistors were substituted with failure equivalent circuit models, and SPICE simulations were performed again to characterize the circuit performance, functionality, and failure behaviors. The simulation shows that the 0.25-mum technology, hot-carrier injection (HCI), and time-dependent dielectric breakdown (TDDB) had significant effects on SRAM-cell stability and voltage-transfer characteristics, while negative bias temperature instability (NBTI) mainly degraded the cell transition speed when the cell state flipped. This illustrative SRAM simulation work proves that, with SPICE and the failure equivalent circuit models, circuit designers can better understand the damage effects of HCI/TDDB/NBTI on the circuit operation, quickly estimate the circuit lifetime, make appropriate performance/reliability tradeoffs, and formulate practical design guidelines to improve the circuit reliability

Analytical Modeling of Realistic Single-Electron Transistors Based on Metal-Oxide-Semiconductor Structure with a Unique Distribution Function in the Coulomb-Blockade Oscillation Region

Novel metal-oxide-semiconductor (MOS)-based single-electron transistors (MOSETs) using band-to-band tunneling mechanism have been fabricated by the conventional silicon-on-insulator (SOI) MOSFET technologies. The fabricated SETs have tunnel barriers and quantum-dot formed by an extremely small channel between two p+-n+ tunnel junctions in the degenerately doped SOI MOSFET. Coulomb oscillation was observed in the subthreshold region at liquid nitrogen temperature and total capacitance of quantum-dot is 2.25 aF which is well matched to the device geometry. In order to validate the operation principle of our device, we have implemented an analytical device model in the simulation program with integrated circuit emphasis (SPICE). SPICE simulation of our model with a unique distribution function has reproduced the experimental results with good agreement for wide gate and drain bias range.

Computer simulation of responses of earth‐return circuits to the AC and DC external excitation

AbstractThe use of the circuit simulation package SPICE (Simulation Program with Integrated Circuit Emphasis) permits the complex analysis of the EMI (electromagnetic interference) on earth‐return circuits. In the approach presented, the earth‐return circuit with excitation by AC signals and transients, as well as with DC energization is modelled as a large multinode electrical equivalent circuit. The circuit is a chain of basic circuits, which are equivalents of homogenous sections of the earth‐return circuit with uniform exposure to the primary interfering electric field associated with the inductive and the conductive influence. The application of controlled voltage and current sources in the basic circuits permit the modelling of coupling effects in systems of earth‐return circuits. Contrary to the analytical methods the SPICE simulation enables one to solve the EMI problems in practical cases connected with: topological complexity of the system considered, non‐homogeneous geometrical and electrical parameters of the earth‐return circuits, non‐homogeneous earth, application of insulating flanges, bonds, earth electrodes in a system of earth‐return circuits, non‐linearity of the system, etc. The SPICE simulation is an alternative and a useful approach to the analysis of EMI problems in earth‐return circuits, when comparing with existing analytical and numerical solutions. The usefulness of the SPICE simulation has been illustrated by examples.

Analysis of 3-D interconnect structures with PEEC using SPICE

This paper discusses the possibilities of using the circuit simulation program, simulation program with integrated circuit emphasis (SPICE) for the simulation of partial element equivalent circuit (PEEC) models. After an introduction into the PEEC method, the simulation of quasi-stationary models is considered. An enhancement of SPICE is described, allowing the simulation of retarded PEEC models. This enables the computation of electric fields radiated from an interconnection structure. With the modified SPICE simulator it is possible to use existing SPICE models and combine them with full wave PEEC models.

Novel behavioral macromodeling using SPICE and its applications to high-voltage engineering education

A novel technique that uses the Simulation Program with Integrated Circuit Emphasis (SPICE) simulation program as a behavioral macromodeling language in solving high-voltage problems is presented. The proposed technique is based on using analog computation along with basic circuit components (resistors, capacitors, etc.) to solve practical problems encountered in the design and analysis of overhead transmission lines for engineering education. Two behavioral macromodels for medium length overhead transmission lines—namely, nominal T and nominal π—have been designed and implemented using the SPICE simulation program. Intensive computer simulations show that the proposed technique gives excellent agreement with practical measurements. © 1999 John Wiley & Sons, Inc. Comput Appl Eng Educ 7: 155–161, 1999

New hybrid integrated laser diode-drivers using microsolder bump bonding: SPICE simulation of high-speed modulation characteristics

This paper proposes two types of new hybrid integrated laser diode (LD)-drivers that use microsolder bump bonding instead of conventional wire bonding. In one, an LD and a driver are flip-chip bonded to each other; in the other, an LD and a driver are flip-chip bonded onto a substrate. Their performances are compared to those of a monolithic LD-driver and a conventional hybrid one using wire bonding by a simulation program with integrated circuit emphasis (SPICE) with particular emphasis on high-speed LD modulation. The nonreturn-to-zero (NRZ) eye patterns modulated at signal speeds up to 30 Gb/s by the new hybrid integrated LD-drivers were hardly inferior to those by the monolithic LD-driver, whereas those by conventional hybrid ones were greatly degraded over 10 Gb/s. The new hybrid integrated LD-drivers are a feasible alternative to monolithic ones for high-speed optical transmitters.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>