scholarly journals Graph-Based Symbolic Technique and Its Application in the Frequency Response Bound Analysis of Analog Integrated Circuits

2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
E. Tlelo-Cuautle ◽  
S. Rodriguez-Chavez ◽  
A. A. Palma-Rodriguez
Keyword(s):  
Monte Carlo ◽  
Integrated Circuits ◽  
Monte Carlo Simulations ◽  
Frequency Response ◽  
Integrated Circuit ◽  
Variational Analysis ◽  
Computing Time ◽  
Nonlinear Constrained Optimization ◽  
Analog Ic ◽  
Analytical Expressions

A new graph-based symbolic technique (GBST) for deriving exact analytical expressions like the transfer functionH(s)of an analog integrated circuit (IC), is introduced herein. The derivedH(s)of a given analog IC is used to compute the frequency response bounds (maximum and minimum) associated to the magnitude and phase ofH(s), subject to some ranges of process variational parameters, and by performing nonlinear constrained optimization. Our simulations demonstrate the usefulness of the new GBST for deriving the exact symbolic expression forH(s), and the last section highlights the good agreement between the frequency response bounds computed by our variational analysis approach versus traditional Monte Carlo simulations. As a conclusion, performing variational analysis using our proposed GBST for computing the frequency response bounds of analog ICs, shows a gain in computing time of 100x for a differential circuit topology and 50x for a 3-stage amplifier, compared to traditional Monte Carlo simulations.

scholarly journals Simulation of Proton Beam Effects in Thin Insulating Films

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ljubinko Timotijevic ◽  
Irfan Fetahovic ◽  
Djordje Lazarevic ◽  
Milos Vujisic
Keyword(s):  
Monte Carlo ◽  
Silicon Nitride ◽  
Integrated Circuits ◽  
Silicon Dioxide ◽  
Monte Carlo Simulations ◽  
Proton Energy ◽  
Transport Parameters ◽  
Insulating Layer ◽  
Insulating Films ◽  
Ultrathin Layers

Effects of exposing several insulators, commonly used for various purposes in integrated circuits, to beams of protons have been investigated. Materials considered include silicon dioxide, silicon nitride, aluminium nitride, alumina, and polycarbonate (Lexan). The passage of proton beams through ultrathin layers of these materials has been modeled by Monte Carlo simulations of particle transport. Parameters that have been varied in simulations include proton energy and insulating layer thickness. Materials are compared according to both ionizing and nonionizing effects produced by the passage of protons.

Fast Calculation of the Statistics of the Forced Response of Mistuned Bladed Disk Assemblies With Friction Contacts

2002 ◽  
Author(s):  
Walter Sextro ◽  
Lars Panning ◽  
Florian Go¨tting ◽  
Karl Popp
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Frequency Response ◽  
Approximate Method ◽  
Natural Frequencies ◽  
Computation Time ◽  
System Response ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Bladed Disk

In turbomachinery one major problem is still the calculation and the optimization of the spatial vibrations of mistuned bladed disk assemblies with friction contacts. Friction contacts are widely used to reduce dynamic stresses in turbine blades. Due to dry friction and the relative motion of the contact planes energy is dissipated. This effect results in a reduction of blade vibration amplitudes. In the case of a tuned bladed disk cyclic boundary conditions can be used for the calculation of the dynamic response. For a mistuned bladed disk the complete system has to be modeled and simulated. To reduce the computation time the so-called substructure method is applied. This method is based on the modal description of each substructure, especially disk and blades, combined with a reduction of the degrees of freedom, to describe the dynamics of each component. The spatial dynamical behavior of each component is considered and described by the mode shapes, natural frequencies and modal damping ratios. Using the Harmonic Balance Method the nonlinear friction forces can be linearized. From here it is possible to calculate the frequency response functions of a mistuned bladed disk assembly with friction contacts. In many cases Monte-Carlo simulations are used to find regions, where the system response is sensitive to parameter uncertainties like the natural frequencies of the blades. These simulations require a large computation time. Therefore, an approximate method is developed to calculate the envelopes of the frequency response functions for statistically varying natural frequencies of the blades. This method is based on a sensitivity analysis and the Weibull-distribution of the vibration amplitudes. From here, a measure for the strength of localization for mistuned cyclic systems is derived. Regions, where localization can occur with a high probability, can be calculated by this method. The mean value and the standard deviation of the vibration amplitudes are calculated by simulation and by the approximate method. The comparisons between the approximate method and the Monte-Carlo simulations show a good agreement. Therefore, applying this method leads to remarkable reduction of computation time and gives a quick insight into the system behavior. The approximate method can also be applied to systems, that include the elasticity of the disk and/or the coupling by shrouds or other friction devices.

scholarly journals An Inclusive Performance Analysis of Single-branch Single-relay AF Transmission in a Mixed Rayleigh-Nakagami-m Fading Environment

2019 ◽  
Vol 3 ◽  
pp. 39-48
Author(s):  
Slimane Benmahmoud
Keyword(s):  
Monte Carlo ◽  
Performance Analysis ◽  
Monte Carlo Simulations ◽  
Ergodic Capacity ◽  
Upper Bounds ◽  
Amplify And Forward ◽  
Single Relay ◽  
Analytical Expressions ◽  
Af Relaying ◽  
Single Branch

In this paper, the end-to-end performance of a single-branch two-hop amplify-and-forward (AF) relaying network in a mixed Rayleigh-Nakagami-m fading environment, is investigated. Four different fading scenarios and three standard relay configurations for each scenario are considered. Exact analytical expressions for the outage probability and tight upper bounds for the ergodic capacity are derived. Results of Monte Carlo simulations are provided to verify the accuracy of the analytical results.

scholarly journals PARALLELIZATION OF MONTE CARLO SIMULATIONS AND SUBMISSION TO A GRID ENVIRONMENT

2004 ◽  
Vol 14 (02) ◽  
pp. 177-196 ◽  
Author(s):  
LYDIA MAIGNE ◽  
DAVID HILL ◽  
PASCAL CALVAT ◽  
VINCENT BRETON ◽  
ROMAIN REUILLON ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Medical Physics ◽  
Tomographic Reconstruction ◽  
Computing Time ◽  
Random Number Generator ◽  
Reconstruction Algorithms ◽  
Software Application ◽  
Image Quantization ◽  
Geographically Distributed

Monte Carlo simulations are increasingly used in medical physics. In scintigraphic imaging these simulations are used to model imaging systems and to develop and assess tomographic reconstruction algorithms and correction methods for improved image quantization. In radiotherapy-brachytherapy the goal is to evaluate accurately the dosimetry in complex phantoms and at interfaces of tissue, where analytic calculations have shown some limits. The main drawback of Monte Carlo simulations is their high computing time. The aim of our research is to reduce the computing time by parallelizing a simulation on geographically distributed processors. The method is based on the parallelization of the Random Number Generator (RNG) used in Monte Carlo simulations. The long serial of numbers used by the sequential simulation is split. Once the partitioning is done, a software application allows the user to generate automatically the files describing each simulation part. Finally, another software executes them on the DataGrid testbed using an API. All these steps have been made transparent for the user by providing a web page asking the user for all the parameters necessary to launch the simulation and retrieve results. Different tests have been done in order to show first, the reliability of the physical results obtained by concatenation of parallelized output data and secondly the time gained for jobs execution.

A Monte Carlo thin Film Simulation for Microcomputers

1982 ◽  
Vol 40 ◽  
pp. 746-747
Author(s):  
D.C. Joy
Keyword(s):  
Thin Film ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Computing Time ◽  
Personal Computers ◽  
Large Computer ◽  
Substantial Investment

Monte Carlo simulations are now widely used as a means of studying the details of electron solid interactions (Heinrich et al 1976). The use of this technique has, however, been limited by the perception that a large computer, and a substantial investment in computing time are required to obtain useful results. This paper describes a Monte Carlo simulation, written in BASIC that is implemented on an APPLE micro-computer, and is readily adapted to most other "personal" computers.

Enhancing an Automatic Analog IC Design Flow by Using a Technology-Independent Module Generator

2015 ◽  
pp. 102-133 ◽  
Author(s):  
António Canelas ◽  
Ricardo Martins ◽  
Ricardo Póvoa ◽  
Nuno Lourenço ◽  
Jorge Guilherme ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
Performance Enhancement ◽  
Design Flow ◽  
Optimization Process ◽  
Ic Design ◽  
Analog Ic ◽  
Benchmark Circuit ◽  
Device Structures

This chapter presents a new methodology to enhance the optimization process of an analog integrated circuit synthesis tool, AIDA-C, by taking into account the floorplan of the circuit. The addition of the new Analog Module Generator (AMG) in the AIDA framework creates the possibility to efficiently explore the circuit floorplan during the optimization process and to improve the quality of the final floorplan by adding complex device structures enhancing the layout matching, symmetry, and routing, reducing some of the non-idealities to which analog integrated circuits are so sensitive. The performance enhancement attained with AMG is demonstrated using a well-known benchmark circuit, optimized by AIDA-C with and without taking into account AMG's complex structures in the evaluation of the circuit's floorplan.

Scanning Electron Microscopy in Hybrid Microelectronics

1976 ◽  
Vol 34 ◽  
pp. 456-457
Author(s):  
S. Khadpe ◽  
R. Faryniak
Keyword(s):  
Integrated Circuits ◽  
Thick Film ◽  
Integrated Circuit ◽  
Failure Modes ◽  
Three Dimensional ◽  
Circuit Components ◽  
Hybrid Microcircuit ◽  
Electrical Connections ◽  
Scanning Electron

The Scanning Electron Microscope (SEM) is an important tool in Thick Film Hybrid Microcircuits Manufacturing because of its large depth of focus and three dimensional capability. This paper discusses some of the important areas in which the SEM is used to monitor process control and component failure modes during the various stages of manufacture of a typical hybrid microcircuit.Figure 1 shows a thick film hybrid microcircuit used in a Motorola Paging Receiver. The circuit consists of thick film resistors and conductors screened and fired on a ceramic (aluminum oxide) substrate. Two integrated circuit dice are bonded to the conductors by means of conductive epoxy and electrical connections from each integrated circuit to the substrate are made by ultrasonically bonding 1 mil aluminum wires from the die pads to appropriate conductor pads on the substrate. In addition to the integrated circuits and the resistors, the circuit includes seven chip capacitors soldered onto the substrate. Some of the important considerations involved in the selection and reliability aspects of the hybrid circuit components are: (a) the quality of the substrate; (b) the surface structure of the thick film conductors; (c) the metallization characteristics of the integrated circuit; and (d) the quality of the wire bond interconnections.

TEM study of phosphorus-implanted pseudomorphic Si0.88Ge0.12 on Si(100)

1995 ◽  
Vol 53 ◽  
pp. 468-469
Author(s):  
N. David Theodore ◽  
Donald Y.C Lie ◽  
J. H. Song ◽  
Peter Crozier
Keyword(s):  
Integrated Circuits ◽  
Heterojunction Bipolar Transistors ◽  
Integrated Circuit ◽  
High Speed ◽  
Room Temperature ◽  
Strain Relaxation ◽  
Bipolar Transistors ◽  
Sige Hbt ◽  
Integrated Circuit Manufacturing ◽  
Microstructural Behavior

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.

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