CAD postprocessing - how to increase quality in board manufacturing

In the absence of interface standards for CAD and CAM systems, the use of CAD data in manufacturing processes has never been as simple as it should be. Usually, CAD data is re-entered manually or transferred by restricted point to point interfaces. The first method carries a high risk of adding new errors which will increase manufacturing costs and dangerously undermine the quality of the manufacturing process. The second method is usually automatic, cutting out the manufacturing engineer and ignoring the fact that the application of his skills is an essential part of the process. Manufacturing engineers ask for the same interactive graphic tools which are available to design engineers. One reason why they ask for this is that CAD data is seldom complete and correct for use in manufacturing. While testers do not need package shapes, they do need information on values, tolerances, component types, etc., and placement machines may use different reference points and component names. Manufacturing also needs a single data source, preferably one file on a disk, and not stacks of papers, tapes and disks, in order to produce a board. This paper presents a way of achieving this goal today, using a graphics software package which constitutes a neutral link between design and manufacturing. The software makes A possible to combine original board data from CAD systems and component data from MRP or Product Planning systems for use in board manufacturing processes like assembly / placement, test, fixturing, rework and repair.