This paper presents a module generator for Digital/Analog Converter (DAC) circuits. A combination of circuit simulation and DAC design equations is used to estimate performance. A new constrained optimization method is used to determine design variable values. The layout is created using stretching and tiling operations on a set of primitive cells. Close coupling of optimization and layout allows accurate incorporation of layout parasitics in optimization. Prototypes have been demonstrated for an 8-bit, 100-MHz specification, driving a 37.5-ohm video load, and a static 10-bit specification, driving a 4mA full-scale output current. Both designs use a 5-V supply in a standard 1.2 µm CMOS process. 1 I. Introduction In mixed-signal integrated circuits, the analog part of the design often occupies a small portion of the physical die area but requires a disproportionately large amount of the design effort and time. One approach for reducing design time is to develop module generators for f...

DSYN generates optimized Digital/Analog Converter (DAC) layouts given a set of specifications including performance constraints, a description of the implementation technology, and a set of design parameters. The generation process consists of a synthesis step followed by a layout step. During synthesis a new constrained optimization method is coupled with combination of circuit simulation and DAC design equations. The layout step uses stretching and tiling operations on a set of primitive cells. Prototypes have been demonstrated for an 8-bit, 100-MS/s specification, driving a 37.5-ohm video load, and a static 10-bit specification, driving a 4mA full-scale output current. Both designs use a 5-V supply in a 1.2 m CMOS process. 1 Biographies Robert R. Neff (member) was with the University of California, Berkeley, CA. He is now with Hewlett Packard Company, Palo Alto, CA 94304. Paul R. Gray (fellow) and Alberto Sangiovanni-Vincentelli (fellow) are with the Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA 94720 . Coorespondence should be directed to: Dr. Robert Neff Hewlett Packard Company 3500 Deer Creek Road, MS 26U-4 Palo Alto, CA 94304-0867 Phone: (415)857-6220 Fax: (415)857-3637 E-mail: neff@hpl.hp.com 1. This research was supported by the Semiconductor Research Corporation under grant 94-DC-324. 2 I.