LDS - A description script for layout templates

Abstract

In this paper a simple declarative language to define layout templates of analog circuits, named Layout Description Script (LDS), is introduced. In contrast to sequential description languages, coding constraints of a template is very easy with LDS. A methodology based on linear programming (LP) is presented to instantiate a layout from a set of LDS statements. Due to the LP formulation, area and wire length minimization is also applied during instantiation. Also a methodology to extract LDS from a pre-drawn layout is presented. These methodologies and the description language itself are illustrated by synthesizing an amplifier. The proposed methodology is able to synthesize a layout in a few seconds.