The cost to produce a printed circuit assembly comes primarily from the cost of components, the cost of manufacturing and the cost of testing.
However, if a printed circuit board (PCB) is designed without consideration or with little consideration of these cost factors, a large penalty is inevitably paid later in production, testing and repair.
Thus, the concept of designing for profitability, the ideal for success, logically includes 'design for manufacturability' (DFM) - manufacturing at the lowest feasible cost and lowest rate of defect introduction - and 'design for testability' (DFT). In fact, a well-planned and executed PCB design is a key ingredient in designing profitability into a product.
Collaborate from the start
Cooperating is hard work. In many companies, there is a cultural barrier between departments, and all too often the PCB design process is seen as the less important link in the end-product chain. Different managers have different goals because they strive to reach their own department's delivery outcomes. It is easy to lose site of the corporate goal of creating a profitable product if that is not the level at which individuals operate. That perceived less-important link in designing a PCB could spell disaster later when your product is manufactured and tested. The case of the weakest link spells many headaches that could quite easily be prevented with some foreknowledge.
In order to produce a PCB product that is manufacturable and testable, hence profitable, all departments need to strive to keep the big picture in mind when setting objectives. The idea here is to be proactive and personally go beyond one's job description. When embarking on a new PCB product, actively enlist the help of others and be willing to help others as well. Work to instill an atmosphere of cooperation between individuals and departments.
Discuss current assemblies and products out in the field so as to identify the opportunities for failures. Every trace, every solder joint, every component and every connector pin presents an opportunity for process failure. Furthermore, board size, routing space, package types, component types, handling, etc, all contribute in a good or bad way to probability of failure. In other words, be aware of the complete fault spectrum for the types of printed circuit assemblies that are designed and manufactured by your company, and try to work with your manufacturing and testing departments to minimise the opportunities for failures.
In recent years, the outsourcing of PCB design and manufacturing processes to professional design bureaux and OEM manufacturers has become an increasing phenomenon. This makes financial sense since these processes are best handled by professionals who are aware of the pitfalls in the design and manufacturing processes due to exposure to a higher volume of products and applications.
Proven PCB CAD tools enhance productivity
Power, precision, performance. These are the things that matter to the dedicated PCB design specialist. A proven CAD system with tested technology and an intuitive layout and editing environment is key to delivering a design solution ahead of the competition. When choosing a PCB design tool, it is important to peer beyond the fancy packaging and the salesman's grin, and to choose a tool that is ultimately your design partner for success. Never underestimate the need for reliable on-the-fly support, and choose a product that is well supported locally should you need technical assistance.
In any project time is critical. Hence, look for productivity features such as high-speed design rule implementation, push-and-shove advanced routing, mixed-signal circuit simulation, and the ability to make customised reports and utilities to extract data from your design.
No matter how much you put into a design, your output files can mean the difference between success and failure. Clear communications with fabricators, solid model form-fit analysis, critical component placement, full Gerber output control - these all help to ensure a smooth passage to manufacture. Be careful to choose a tool that offers full design output and documentation support, as well as support for IDF, ODB++, extensive DXF import/export, True-Type font and CAM output formats. A fluid exchange of design data between the PCB design tool and mechanical designers helps ensure accuracy.
Probably one of the most important investments of all is to send one's PCB designer on a recognised course to enhance his/her PCB design skills, not only to use the tool more efficiently, but also to explore other aspects of the full product development cycle. A small 2-3 day investment will result in a more equipped design professional - a key link to the success of the project.
At Advanced Energy, the PCB design services department provides all the PCB layouts for the company's process power, thermal management and gas flow products. The demand of this department is very high - it cannot afford to spend time on the difficulties associated with working with complex electronic design software, or waste money on the unwanted 'bells and whistles' offered by a number of software vendors. The department must work efficiently, and watch its bottom line as the tech industry recovers from the recent economic downturn.
For Advanced Energy, it was Altium's P-CAD that met its business needs. On average, the department creates 25 to 30 designs per month, and of these, cycle time is approximately six days (that is, from start date of PCB layout to completion of PCB layout.) To achieve such short cycle times, and maintain high levels of productivity when moving from design layout to board completion, the department required software that was easy to use but also contained advanced features for high quality board designs, and additionally was suitably cost-effective.
According to Advanced Energy: "Not only is P-CAD reasonably priced, but product service upgrades are free and annual maintenance fees are low. There are nine PCB designers in the department using the system on a regular basis - they rarely 'get in trouble' for it is easy to use, and less complex than competing products. Furthermore, the software is intuitive and new engineers can easily learn it. The P-CAD forum is also an excellent resource for the designers."
The PCB department is also regularly utilising CAMtastic, Altium's PCB CAM tool. This provides extensive PCB CAM preview and verification capabilities with a range of analyses and editing features, like fabrication-specific design rule checks and fabrication files.
It is important to catch problems before they go downstream, and the department also attributes its operational efficiencies to the ability to customise P-CAD with DBX, in addition to allowing programming options with ASCII format. The attributes of this open database helps the designers identify areas of error or concern before the design goes to manufacturing. This is of particular importance as the department faces ongoing challenges associated with design for manufacturability and test (DFX).
The department is operating now at extremely efficient levels in terms of both cost and performance, and recently completed one of its most complex designs from schematic to PCB layout in just 15 days. The design task was a 12-layer design incorporating nine different split planes on a board. It has three BGAs and is very dense in that it contains 1500 components populated on both sides. The engineer driving the project was also very critical on where he wanted the components placed and routed. This did not delay the design process as P-CAD's relay feature allows for easy file transfer. As the designers were not working with a complex vault system they were able to pass source files to him so he could do checks and get them back quickly.
DFM, DFT ensure profitability
Design for manufacturability and test are critical to the success and overall quality of any product. The name EDA Technologies has been synonymous with high quality PCB design for more than a decade in South Africa. The company is a forerunner in presenting internationally-recognised DFM and DFT courses locally, and is proficient in these essential methodologies. EDA Technologies also offers various advanced electronics and PCB design courses to companies and educational institutions, and has trained hundreds of professionals over the years.
To this team of professionals, 'Design for Profitability' is not just another PCB industry buzzword. EDA Technologies works closely with clients' engineering, manufacturing and quality personnel, to bring even the most demanding board design to life.
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