“You see what we have here is a failure to communicate.” This too often used statement is a testament to the inability of the meaning being conveyed to be accurately received or understood. The irony is that this situation commonly occurs even when the speaker and listener both have a good grasp of the language being used. As with most information transfers such as this, the failure is not with what is being said, but with what is not.
For PCBA design and development, the communication for the design intent can often be lacking. The consequences of this can show up throughout the manufacturing stage of development. For example, extensive back and forth with your CM and quote delays, result from deficit design intent communication. In this article, effective digital design intent transfer from developer to manufacturer is presented, after clearly defining the importance of evaluating and understanding design intent.
Design Intent Defined
Associating intent with the complex process of designing and building circuit boards may seem a bit awkward. Yet, it is not difficult to recognize the parallels between PCBA design and artistic creation. As with any creative manifestation, building boards requires synchronization of the manufacturing process with the developer’s initial idea or intent. This integration can only occur by first acknowledging the differing perspectives of the developer and CM, defined below.
|From the developer’s vantage point, the design intent is to meet the functionality, performance and reliability objectives as specified by or for their customer’s product needs. This intent is explicitly embodied in design decisions; such as component selection, choice of materials and PCBA layout that are included in the design file(s).|
|Board manufacturers in most cases are not aware of how the PCBAs they make should perform, nor do they typically need to be. Instead, their focus is on quality control and the board’s manufacturability and structural integrity. And their expectation is that design intent should be incorporated in the design file(s) specifications enabling board builds within the capabilities of their equipment and processes.|
Although the developer’s and CM’s perspectives have different objectives, they are linked by the contents of the design file or package. Therefore, the level to which the board build reflects the developer’s plan is dependent on the CM evaluating and understanding the design intent from the transferred package.
Efficiently Evaluating and Understanding Design Intent
When transferring PCBA designs to manufacturers, it has been traditional and to a great extent is still contemporary to use a Gerber file format despite increasing preference by CMs for alternatives; such as native CAD files, IPC-2581 and OBD++. This persistence is likely due to the fact that virtually all circuit design software programs can export Gerbers and all CMs will accept them. However, a recent State of the Market Report based upon a survey of PCBA industry professionals, academicians and others conducted by Electronic Design indicates the use of digital electronic design automation (EDA) smart files for design data transfer was the preference of higher-level managers and larger companies.
EDA smart files are digitized design data representations in contrast to Gerbers, which are mostly images. In this digitized format, more detailed and accurate data can be transferred to the manufacturer, negating imprecision which is one of the major issues with Gerbers. Precision becomes increasingly important when building critical system boards; including PCBAs for aerospace systems, class 3 and some class 2 medical devices and EV and AV automotive systems. Complexity not only applies to the design specifications, but also to the manufacturing techniques necessary to perform the process step.
The Engineer's Guide to PCBA Manufacturing Complexity
Fabrication recovery complexity example (Source)
The figure above illustrates the high recovery complexity that can be associated with fabrication depending upon where a defect occurs in the process. For example, errors at step 11 require restarting the entire fabrication process. This translates into longer turnaround time for the boards and higher manufacturing and development costs.
|Tempo’s Software-Driven Smart Factory Delivers the Industry’s Leading Custom Turnkey PCBA Manufacturing Services
EDA digital files are the best design data transfer formats for efficient design intent incorporation into the manufacturing process. As the industry’s leading manufacturer of prototypes and low volume PCBAs, Tempo Automation, is capable of utilizing all major design file types. Digital file formats are proven to be ideal for the greatest process efficiency.
In order to get started on the best path, Tempo furnishes information for your DFM checks and enables you to easily view and download DRC files. If you’re an Altium Designer or Cadence Allegro user, you can simply add these files to your PCB design software. For Mentor Pads or other design packages, you’ll have access to DRC information in other CAD formats and Excel.
If you’re ready to have your design manufactured, try our quote tool to upload your CAD and BOM files. If you want more information on how to design and facilitate evaluating and understanding design intent, contact us.