Electric (software) - Powerful Design Style

Powerful Design Style

Electric has a powerful way of doing integrated circuit (IC) layout. The system considers integrated circuits to be composed of nodes and arcs. Nodes are circuit elements such as transistors and contacts. Arcs connect the nodes. This style of design is quite different from typical IC layout systems, such as Magic and Cadence, which do IC layout by manipulating polygons on different layers of the wafer.

This powerful design style makes it possible for the designer to run Layout Versus Schematic (LVS) on layouts which are not yet Design Rule Check (DRC) clean. This is extremely useful during the design process. It also makes it possible for the design tool to back-annotate wire-lengths from a layout to a schematic even if the layout is not yet DRC clean. Finally, because layouts are stored internally as a graph (rather than "paint"), the LVS check is exceptionally fast, often running in under a second on full-chip designs (such as the recent Marina chip). The ability to run LVS near-instantaneously on large designs has a big impact on ease of design.

It has been observed that people with no previous experience in IC layout are comfortable with Electric's unusual style, but those who have done IC layout on other systems find Electric difficult to use.

One added advantage of the nodes-and-arcs view of a circuit is that it is possible to add layout constraints to the arcs. There are only a small set of these constraints, but with careful placement, the circuit can be programmed to stay properly connected when physical changes are made.