A methodology for the automatic synthesis of full-custom IC layout with analog constraints is presented. The methodology guarantees that all performance constraints are met when feasible, or otherwise infeasibility is detected as soon as possible, thus providing a robust and efficient design environment. In the proposed approach, performance specifications are translated into lower level bounds on parasitics or geometric parameters, using sensitivity analysis. Bounds can be used by a set of specialized layout tools performing stack generation, placement, routing and compaction. For each tool, a detailed description is provided of its functionality, of the way constraints are mapped and enforced, and of its impact on the design flow. Examples drawn from industrial applications are reported to illustrate the effectiveness of the approach. Keywords--- Layout, Analog Design, Constraint-Driven Layout. I. Introduction The layout of analog circuits is intrinsically more difficult than the d...

In this paper, we present a new approach for realistic worst-case analysis of VLSI circuit performances and a novel methodology for circuit performance optimization. Circuit performance measures are modeled as response surfaces of the designable and uncontrollable (noise) parameters. Worst-case analysis proceeds by first computing the worst-case circuit performance value and then determining the worst-case noise parameter values by solving a nonlinear programming problem. A new circuit optimization technique is developed to find an optimal design point at which all of the circuit specifications are met under worst-case conditions. This worst-case design optimization method is formulated as a constrained multi-criteria optimization. The methodologies described in this paper are applied to several VLSI circuits to demonstrate their accuracy and efficiency. Keywords Worst-case analysis, worst-case design optimization. I. Introduction I NEVITABLE fluctuations in the manufacturing proces...

A general methodology is presented for the generation of a complete set of constraints on interconnect parasitics, parasitic mismatch and on the physical topology of analog circuits. The parasitic and matching constraints are derived from highlevel performance specifications by means of sensitivity analysis in time and frequency domain using quadratic optimization. Topological constraints are obtained by using sensitivity and matching information on devices and interconnect as well as graph-based techniques to extract the necessary geometric information. 1 Introduction The design of analog circuits is often a difficult task compared with a digital one of similar complexity because of the higher number of specifications and the importance of second order effects. In addition, the continuously growing complexity of analog integrated circuits has required a better control over the design quality and the redefinition of tasks like module generation and floorplanning. The performances of...

This paper focuses on electronic design at circuit level. The use of evolutionary algorithms to this application is discussed and a trade off to existing approaches is investigated. The design and analyzing task at this level is described in detail. As example a 1-bit full adder design in static CMOS is inspected with regard to power consumption and delay. In algorithmic scope both, single- and multi-objective optimization are regarded here. 1 Introduction Development of new concepts to low power design needs a comparison to existing alternatives. Independant of the abstract level an optimal decision in lower, as well as in upper levels is essential to determine the concepts potential. This paper focuses on the circuit level as a parameter adjustment task. Instead of commonly used local meliorating procedure evolutionary algorithms as a global optimum seeking method are used here. A global search could guide the designer to alternative designs far away from usual ones. This becomes m...