Results 1 
8 of
8
Mismatch Analysis and Direct Yield Optimization by SpecWise Linearization and FeasibilityGuided Search
 IEEE DAC
, 2001
"... We present a new method for mismatch analysis and automatic yield optimization of analog integrated circuits with respect to global, local and operational tolerances. Effectiveness and efficiency of yield estimation and optimization are guaranteed by consideration of feasibility regions and by perfo ..."
Abstract

Cited by 21 (1 self)
 Add to MetaCart
We present a new method for mismatch analysis and automatic yield optimization of analog integrated circuits with respect to global, local and operational tolerances. Effectiveness and efficiency of yield estimation and optimization are guaranteed by consideration of feasibility regions and by performance linearization at worstcase points. The proposed methods were successfully applied to two example circuits for an industrial fabrication process.
Recent Results In Solving Index 2 DifferentialAlgebraic Equations In Circuit Simulation
 SIAM J. Sci. Stat. Comput
, 1996
"... . In electric circuit simulation the charge oriented modified nodal analysis may lead to highly nonlinear DAEs with low smoothness properties. They may have index 2 but they do not belong to the class of Hessenberg form systems that are well understood. In the present paper, on the background of a d ..."
Abstract

Cited by 6 (2 self)
 Add to MetaCart
. In electric circuit simulation the charge oriented modified nodal analysis may lead to highly nonlinear DAEs with low smoothness properties. They may have index 2 but they do not belong to the class of Hessenberg form systems that are well understood. In the present paper, on the background of a detailed analysis of the resulting structure, it is shown that charge oriented modified nodal analysis yields the same index as the classical modified nodal analysis. Moreover, for index 2 DAEs in the charge oriented case, a further careful analysis with respect to solvability, linearization and numerical integration is given. Key words. Differentialalgebraic equations, index 2, circuit simulation, IVP, numerical integration, BDF, defect correction. AMS subject classifications. 65L10 1. Introduction. In modern circuit simulation, the socalled charge oriented modified nodal analysis is preferred for different reasons ([4], [7]). The resulting DAEs have low smoothness properties. They may h...
The Generalized Boundary Curve  A Common Method for Automatic Nominal Design and Design Centering of Analog Circuits
 IN PROCEEDINGS DESIGN, AUTOMATION AND TEST IN EUROPE CONFERENCE AND EXHIBITION 2000
, 2000
"... In this paper, a new method for analog circuit sizing with respect to manufacturing and operating tolerances is presented. Two types of robustness objectives are presented, i.e. parameter distances for the nominal design and worstcase distances for the design centering. Moreover, the generalized bou ..."
Abstract

Cited by 3 (1 self)
 Add to MetaCart
In this paper, a new method for analog circuit sizing with respect to manufacturing and operating tolerances is presented. Two types of robustness objectives are presented, i.e. parameter distances for the nominal design and worstcase distances for the design centering. Moreover, the generalized boundary curve is presented as a method to determine a parameter correction within an iterative trust region algorithm. Results show that a significant reduction in computational costs is achieved using the presented robustness objectives and generalized boundary curve.
Network Approach and DifferentialAlgebraic Systems in Technical Applications
 Surv. Math. Ind
, 1999
"... this paper we concentrate on the second step, especially the network approach for the automatic generation of the mathematical model. We achieve a descriptor formulation which is characterized by a differentialalgebraic system (DAE). Their numerical solution creates new difficulties, which are cha ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
this paper we concentrate on the second step, especially the network approach for the automatic generation of the mathematical model. We achieve a descriptor formulation which is characterized by a differentialalgebraic system (DAE). Their numerical solution creates new difficulties, which are characterized by the index concept.
Analog Circuit Sizing using Adaptive WorstCase Parameter Sets
, 2002
"... In this paper, a method for nominal design of analog integrated circuits is presented that includes process variations and operating ranges by worstcase parameter sets. These sets are calculated adaptively during the sizing process based on sensitivity analyses. The method leads to robust designs w ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
In this paper, a method for nominal design of analog integrated circuits is presented that includes process variations and operating ranges by worstcase parameter sets. These sets are calculated adaptively during the sizing process based on sensitivity analyses. The method leads to robust designs with high parametric yield, while being much more efficient than design centering methods.
ON METHODS FOR ORDERING SPARSE MATRICES IN CIRCUIT SIMULATION
"... Recently proposed methods for ordering sparse symmetric matrices are discussed and their performance is compared with that of the Minimum Degree and the Minimum Local Fill algorithms. It is shown that these methods applied to symmetrized modified nodal analysis matrices yield orderings significantly ..."
Abstract

Cited by 1 (1 self)
 Add to MetaCart
Recently proposed methods for ordering sparse symmetric matrices are discussed and their performance is compared with that of the Minimum Degree and the Minimum Local Fill algorithms. It is shown that these methods applied to symmetrized modified nodal analysis matrices yield orderings significantly better than those obtained from the Minimum Degree and Minimum Local Fill algorithms, in some cases at virtually no extra computational cost. 1.
A Shooting Method for the DAE System of the Network Equation
"... For a solution ϕ(t; x0) with ϕ(0; x0) = x0 of the given implicit DAEsystem F ( ˙x(t), x(t), t) = 0, a consistent initial value x0 must be found such that the periodicity condition x(0) − x(τ) = 0, (1) where τ is the period of the input and output signal is fulfilled. Similar to multiple shootin ..."
Abstract
 Add to MetaCart
For a solution ϕ(t; x0) with ϕ(0; x0) = x0 of the given implicit DAEsystem F ( ˙x(t), x(t), t) = 0, a consistent initial value x0 must be found such that the periodicity condition x(0) − x(τ) = 0, (1) where τ is the period of the input and output signal is fulfilled. Similar to multiple shooting methods for high dimensional ODE systems, the nonlinear equation for the unknown initial state x0 is formulated as the minimization problem min x0∈IR n ϕ(τ; x0) − x0  2 2. For the initial state of a periodical solution the residual vanishes. A Gauss–Newton method is used to solve the minimization problem. It consists of a sequence of linear approximations of the residual function to be minimized. For the actual approximation of the initial state x i 0, a correction ∆x i is determined as the solution of the linearization of the argument of the minimization problem: and ∆x i is the solution of min ∆x i ∈IR x i+1 0 = xi 0 + ∆x i, i = 0, 1,...
A NEW METHOD FOR ORDERING SPARSE MATRICES AND ITS PERFORMANCE IN CIRCUIT SIMULATION
"... Local algorithms for obtaining a pivot ordering for sparse symmetric coefficient matrices are reviewed together with their mathematical background and appropriate data structures. Recently proposed heuristics as well as improvements to them are discussed, and their performance, mainly in terms of th ..."
Abstract
 Add to MetaCart
Local algorithms for obtaining a pivot ordering for sparse symmetric coefficient matrices are reviewed together with their mathematical background and appropriate data structures. Recently proposed heuristics as well as improvements to them are discussed, and their performance, mainly in terms of the resulting number of factorization operations, is compared with that of the Minimum Degree and the Minimum Local Fill algorithms. It is demonstrated that a combination of Markowitz ’ algorithm with these symmetric methods applied to the unsymmetric matrices arising in circuit simulation is capable of accelerating the simulation significantly. 1.