A power bus channel router

The author presents an effective and practical implementation of a dogleg channel router which can handle logic as well as power and ground signals in a channel. The bus is routed with uniform width throughout the entire channel. In a large channel, it may be desirable to route the bus with different widths at different parts of the channel. The power-bus routing procedure described provides an easy way to route power and ground signals in a VSLI chip. Previously, only logic signals were routed and empty spaces were reserved at the top or bottom side of a channel. The power and ground routing was then added manually in these reserved regions, using a graphical editor. The logic signals have to take a poly underpass whenever they cross a power or ground signal. This sometimes requires extensive manual edits on the existing routing. The power-bus routing procedure eliminates the error-prone and time-consuming work of routing the power and ground bus manually