Global Design of Analog Cells Using Statistical Optimization Techniques
We present a methodology for automated sizing of analog cells using statistical optimization in a simulation based approach. This methodology enables us to design complex analog cells from scratch within reasonable CPU time. Three different specification types are covered: strong constraints on the electrical performance of the cells, weak constraints on this performance, and design objectives. A mathematical cost function is proposed and a bunch of heuristics is given to increase accuracy and reduce CPU time to minimize the cost function. A technique is also presented to yield designs with reduced variability in the performance parameters, under random variations of the transistor technological parameters. Several CMOS analog cells with complexity levels up to 48 transistors are designed for illustration. Measurements from fabricated prototypes demonstrate the suitability of the proposed methodology.
KeywordsDesign Objective Phase Margin Cool Schedule Global Design Integrate Circuit Design
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- 2.Meixenberger, C., Henderson, R., Adder, L. and Degrauwe, M., “Tools for analog design,” Proc. Workshop on Advances in Analog Circuit Design, pp. 357–368, Scheveningen, The Netherlands, 1992.Google Scholar
- 7.Sheu, B. J., Lee, J. C. and Fung, A. H., “Flexible architecture approach to knowledge-based analogue IC design,” /EE Proceedings, Vol. 137, Pt. G, pp. 266–274, August 1990.Google Scholar
- 10.Makris, C. and Toumazou, C., “ISAID: Qualitative reasoning and trade-off analysis in analog IC design automation;” Proc. IEEE/nt. Symp. on Circuits and Systems, pp. 2364–2367, 1992.Google Scholar
- 11.Jongsma, J. et al., “An open design tool for analog circuits;” Proc. Int Symp. on Circuits and Systems, pp. 2000–2003, 1991.Google Scholar
- 12.Fernandez, F. V., Rodriguez-Vazquez, A. and Huertas, J. L., “Interactive AC modeling and characterization of analog circuits via symbolic analysis,” Analog Integrated Circuit and Signal Processing, Vol. 1, pp. 183–208, Kluwer, Nov. 1991.Google Scholar
- 15.Campbell, C. A., HSPICE User Manual. Meta Software Inc., 1988.Google Scholar
- 17.Roberge, J. K., Operational Amplifiers: Theory and Practice. John Wiley & Sons Inc., New York, 1975.Google Scholar
- 23.Medeiro, F., Perez Verdu, B., Rodriguez-Vazquez, Y. and Huertas, J. L., “A tool for automated design of sigma-delta modulators using statistical optimization,” Proc. of ISCAS ’83, pp. 1373–1376. Chicago, May, 1993.Google Scholar