The trends in the electronic industry are toward higher functionality, in a smaller volume, and at lower costs. Thus, the issue of manufacturability (namely quality, liability and consistency) of these designs, is becoming a major (high-cost) issue in the manufacturing of PCB's.

Design for manufacturability is the concern of every designer and manufacturer, mainly of high-density SMD printed circuit boards. It is the concern of the designer due to time-to-market, product reliability and cost issues. It concerns the manufacturer because of turnaround time, testability and profitability issues.

The lack of an industry standard for data transfer from the CAD to CAM format is one of the symptoms of miscommunication between designers and manufacturers. The different terminology used by both sides reflects the lack of mutual understanding. On the one hand, manufacturers do not understand the functional design constraints. While on the other hand, designers lack the understanding of PCB production. Furthermore, designers do not realize the major distinction between the DRC used by the CAD system on the CAD database, and the MRC (Manufacturability Rules Checker) used in the manufacturing data (usually Gerber) that represents a series of trade-offs affecting manufacturing yields and costs.

Too often, the DFM analysis is not done concurrently with the design, the manufacturability issues are analyzed only as an aftermath, while the design is completed and the production data has been delivered to production. Manufacturers as well as designers feel that this stage of analysis should be done further "upstream" on the designers premises, dramatically reducing the total cycle time from concept to product.

The inevitable conclusion is that a DFM solution needs to resolve manufacturability concerns at the early stage of the design to reduce costs, gain on time-to-market and improve communication.

Bio:
David Furst worked for more than 10 years as a PCB designer in a government lab. In 1985, he joined Daisy, working in Technical Marketing for Daisy's Board Master CAD tool. Since 1990, he has been employed by Orbotech, mainly in the field of CAM solutions.