A SPARSE MATRIX SOLVER FOR GENERAL CIRCUIT SIMULATION

• Main Authors: Jian-Ming Shyu, 徐建明
• Other Authors: Prof. Yao-Tsung Tsai
• Format: Others
• Language: en_US
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/27605926127934185346

碩士 === 國立中央大學 === 電機工程研究所 === 83 === This thesis describes a sparse matrix solver for general circuit simulation. Especially in VLSI circuit simulation, the mathematical model of the circuits introduce very large sparse systems of linear equations. The sparse matrix solver is developed to enhance the performance of circuit simulation. In order to enhance simulation speed and maintain stability, the Partial Gauss-Seidel scheme (PGS) is used as the matrix solution method. This scheme combines direct solution using LU factorization and iterative solution using Gauss-Seidel relaxation. It can both have slower growth rate and avoid divergence problem. In order to store the sparse matrices efficiently, linked lists are used as the storage scheme. Linked lists have the advantage that they can change size dynamically, therefore they are quite accommodative to the generation of fill-ins in direct methods. The implementation of LU factorization with linked lists is demonstrated. Besides, the ordering strategy that is helpful to maintain sparsity is also implemented benefit brought by this strategy is presented. Finally, the performance of this sparse matrix solver in circuit simulation is demonstrated. A circuit simulator was developed to test the sparse matrix solver. AC analysis of simple RC circuits and transient analysis of amorphous-silicon thin-film transistor circuits were executed. The waveforms of a LCD panel were obtained. The comparisons between PGS solution and direct solution are presented. The results shows that the answers provided by them are indistinguishable while PGS solution spent less time.