-
- News
- Books
Featured Books
- design007 Magazine
Latest Issues
Current IssueLevel Up Your Design Skills
This month, our contributors discuss the PCB design classes available at IPC APEX EXPO 2024. As they explain, these courses cover everything from the basics of design through avoiding over-constraining high-speed boards, and so much more!
Opportunities and Challenges
In this issue, our expert contributors discuss the many opportunities and challenges in the PCB design community, and what can be done to grow the numbers of PCB designers—and design instructors.
Embedded Design Techniques
Our expert contributors provide the knowledge this month that designers need to be aware of to make intelligent, educated decisions about embedded design. Many design and manufacturing hurdles can trip up designers who are new to this technology.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - design007 Magazine
Designing in a Vacuum Q&A: Carl Schattke
May 11, 2022 | Andy Shaughnessy, Design007 MagazineEstimated reading time: 3 minutes
Not long ago, I caught up with Carl Schattke, CEO of PCB Product Development LLC and a longtime PCB designer, for his thoughts on “designing in a vacuum.” As Carl points out, if you follow PCB design best practices, knowing the identity of your fabricator is not a “must-have.” He also offers some communication tips for discovering the information you do need, including one old-fashioned technique—just asking for it.
Andy Shaughnessy: Carl, how often do you design a board without knowing who is going to fabricate and/or assemble it?
Carl Schattke: It’s pretty often that the design will start and get completed, or nearly completed, without any board vendor involvement. This is far more common if it’s a standard stackup and a routine process.
For sequential lamination, rigid-flex and flex boards, it’s very rare to not involve the board vendor early on. Also, if there are multiple differential pair impedances on different layers, it’s much more likely a request to the board vendor will be made at the start of placement before routing commences.
Shaughnessy: Why do you think so many designers have no idea who is going to manufacture their boards?
Schattke: It’s nice to have this information, but it’s not a must-have. By following general rules for volume manufacturing, you should be able to get the board built by the vast majority of UL-listed board shops. EEs and purchasing people are typically very busy and they don’t have time to do tasks until they need to be done. The can that can be kicked down the road usually is.
It’s up to the PCB designer to request a stackup with impedance values and HDI rules if the board is higher up on the high-tech scale. None of us want to waste time. If the board is a common low-risk build, the build and rework risk is low if you have incomplete data about who will build the board. When we start using exotic materials and sequential laminations with varied copper weights and high layer counts, it would be foolish not to involve the PCB vendor on the design start.
Dense designs require going right up to the edge of the rules without breaking them. To do that, you need to review the process and your expectations with the vendor to make sure they can build what you design. To do otherwise could put hundreds of hours of work at risk for rework, and no one wants that.
Shaughnessy: What other missing information or data do you find yourself having to “design around”?
Schattke: Where do we start with this question? I would say that the need to get something out the door ASAP drives many designs to start in a state of partial completion. The primary risk of starting PCB layout too early is that the optimal result may not be obtained. Common missing items include incomplete schematics, or incomplete sections of the schematics, and missing current information needed for calculating trace widths.
Other missing information includes voltage clearance rules from one class of nets to another, and missing nomenclature requirements like part numbers, assembly numbers, test marking, and any other special text. Board finish and copper weight are often not provided, and the designer will decide what is best then. The environment the product will be used in is very important for the board design, and this is often missing. Mechanical outline drawings are often incomplete and follow-up details have to be requested.
To read this entire conversation, which appeared in the May 2022 issue of Design007 Magazine, click here.
Suggested Items
Insulectro’s 'Storekeepers' Extend Their Welcome to Technology Village at IPC APEX EXPO
04/03/2024 | InsulectroInsulectro, the largest distributor of materials for use in the manufacture of PCBs and printed electronics, welcomes attendees to its TECHNOLOGY VILLAGE during this year’s IPC APEX EXPO at the Anaheim Convention Center, April 9-11, 2024.
ENNOVI Introduces a New Flexible Circuit Production Process for Low Voltage Connectivity in EV Battery Cell Contacting Systems
04/03/2024 | PRNewswireENNOVI, a mobility electrification solutions partner, introduces a more advanced and sustainable way of producing flexible circuits for low voltage signals in electric vehicle (EV) battery cell contacting systems.
Heavy Copper PCBs: Bridging the Gap Between Design and Fabrication, Part 1
04/01/2024 | Yash Sutariya, Saturn Electronics ServicesThey call me Sparky. This is due to my talent for getting shocked by a variety of voltages and because I cannot seem to keep my hands out of power control cabinets. While I do not have the time to throw the knife switch to the off position, that doesn’t stop me from sticking screwdrivers into the fuse boxes. In all honesty, I’m lucky to be alive. Fortunately, I also have a talent for building high-voltage heavy copper circuit boards. Since this is where I spend most of my time, I can guide you through some potential design for manufacturability (DFM) hazards you may encounter with heavy copper design.
Trouble in Your Tank: Supporting IC Substrates and Advanced Packaging, Part 5
03/19/2024 | Michael Carano -- Column: Trouble in Your TankDirect metallization systems based on conductive graphite or carbon dispersion are quickly gaining acceptance worldwide. Indeed, the environmental and productivity gains one can achieve with these processes are outstanding. In today’s highly competitive and litigious environment, direct metallization reduces costs associated with compliance, waste treatment, and legal issues related to chemical exposure. What makes these processes leaders in the direct metallization space?
AT&S Shines with Purest Copper on World Recycling Day
03/18/2024 | AT&SThe Styrian microelectronics specialist AT&S is taking World Recycling Day as an opportunity to review the progress that has been made in recent months at its sites around the world in terms of the efficient use of resources: