Symbolic behavioral model generation of current-mode analog circuits

A novel extended method to approximate the behavioral model of current-mode analog circuits (CMACs) is presented. The nullor is employed to model the behavior of a MOS Transistor (MOST) together with its parasitic elements. In a first part, the signal-path (SP) into a CMAC is approached by using the nullor properties. In the second part, the behavioral model associated to each MOST is generated and it is more simple in comparison with the original model. As a consequence, in the third part, an admittance matrix of reduced size is built and used to compute small-signal characteristics of CMACs, where the order is given by the number of SP-nodes minus the number of nullors. The proposed technique is illustrated by computing the fully-symbolic transfer function of a Positive Second Generation Current Conveyor (CCII+) and compared with Hspice simulation.

[1]  Eckhard Hennig,et al.  A GENERIC CIRCUIT MODELING STRATEGY COMBINING SYMBOLIC AND NUMERIC ANALYSIS , 1998 .

[2]  Joel R. Phillips.  Automated extraction of nonlinear circuit macromodels , 2000, Proceedings of the IEEE 2000 Custom Integrated Circuits Conference (Cat. No.00CH37044).

[3]  Lars Hedrich,et al.  Equation-based behavioral model generation for nonlinear analog circuits , 1996, DAC '96.

[4]  Yong P. Chen,et al.  A Quadratic Method for Nonlinear Model Order Reduction , 2000 .

[5]  Jacob K. White,et al.  A trajectory piecewise-linear approach to model order reduction and fast simulation of nonlinear circuits and micromachined devices , 2001, IEEE/ACM International Conference on Computer Aided Design. ICCAD 2001. IEEE/ACM Digest of Technical Papers (Cat. No.01CH37281).

[6]  J.I. Alonso,et al.  A new approach for the extraction of SPICE compatible models from measured parameters of microwave circuits , 1998, 1998 IEEE MTT-S International Microwave Symposium Digest (Cat. No.98CH36192).

[7]  C. Sanchez-Lopez,et al.  Behavioral model generation for symbolic analysis of analog integrated circuits , 2005, International Symposium on Signals, Circuits and Systems, 2005. ISSCS 2005..

[8]  Francisco V. Fernández,et al.  Symbolic Analysis Techniques , 1998 .

[9]  Roland W. Freund,et al.  Efficient linear circuit analysis by Pade´ approximation via the Lanczos process , 1994, EURO-DAC '94.

[10]  Georges Gielen,et al.  Symbolic analysis methods and applications for analog circuits: a tutorial overview , 1994, Proc. IEEE.

[11]  Francisco V. Fernández,et al.  Symbolic analysis techniques : applications to analog design automation , 1998 .