ALE: a layout generating and editing system for analog LSIs

An analog LSI layout design system called ALE (analog layout editor) is described. It is applicable to block layouts for bipolar analog LSIs. ALE has two functions: a layout generator and a layout editor. With the layout generator, layouts are generated from circuit diagrams, automatically preserving the relative positions of device cells and wires. Therefore, when circuit constraints are expressed in the circuit diagram, the generated layout satisfies these conditions. The layout editor, which can be used for either circuit diagrams or layouts, provides interactive tools, making it easier to take into account constraints particular to analog circuits. This system reduces layout design time by up to 50% without any degradation of characteristics such as layout area and circuit performance