Accession Number : ADD011808

Title :   Routing Method in Computer Aided Customization of a Two Level Automated Universal Array.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE ARMY WASHINGTON DC

Personal Author(s) : Smith,D C ; Noto,R

Report Date : 02 Jul 1985

Pagination or Media Count : 56

Abstract : This patent application pertains to a routing method implemented in the stored programs of a digital computer which is programmably operated to generate the wire interconnect masks for a two level metallization automated universal array having undefined roadbeds between rows of cells comprised of identical semiconductor device basic units which are futher interconnected to provide a particular integrated circuit structure. Conductor routing is provided by a computer aided design system that, among other things, carries out a route analysis process which determines in which roadbed each wire should be tentatively routed in conjunction with generating a routing density profile for minimizing congestion for a particular circuit design and when the roadbed density is exceeded, certain wires are removed under a set of criteria for routing by a pathfinder routing process. Following route analysis, detailed routing and rerouting is performed sequentially by a direct routing process, a greedy channel routing process, and a pathfinder routing process with rerouting being performed after each channel router and pathfinding process. Furthermore, the greedy channel routing process makes a single pass from left to right in all wires which cross successive points simultaneously and, if necessary, deleting a wire or wires which are then rerouted by the pathfiniding process.

Descriptors :   *PATENT APPLICATIONS, *ROUTING, *COMPUTER AIDED DESIGN, *INTEGRATED CIRCUITS, CELLS, CHANNELS, CIRCUITS, DENSITY, DIGITAL COMPUTERS, FOUNDATIONS(STRUCTURES), PROFILES, RAILROADS, SEMICONDUCTOR DEVICES, STRUCTURAL PROPERTIES, WIRE

Subject Categories : Electrical and Electronic Equipment
      Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE