Design for Manufacturability Strategies at the PCB Level
We spoke to experts at a printed circuit board assembly house to learn more about Design for Manufacturability (DFM) strategies. The goal: Ensuring that device designs can be successfully manufactured.
Medical device designs are focused on giving healthcare providers new tools to deliver better patient care and outcomes. Paving the way to these end results is a series of prototypes that enable OEMs to efficiently produce high-quality devices on deadline, at the lowest cost. Design for manufacturability (DFM) is a strategy that helps optimize the product development process, extending from initial design to end product. DFM helps eliminate problems early in the process, when it’s easiest to solve them, and finds efficiencies across the supply chain.
DFM encompasses electronics design, material selection, vendor selection, regulatory compliance, and other factors that contribute to device manufacturability. One way to navigate this process is to enlist the help of a printed circuit board assembly (PCBA) house that has the ability to analyze the manufacturability of a design and the availability of the components specified.
To learn more, we talked to Ryan Saul, vice president of manufacturing at Tempo Automation, a San Francisco company that specializes in the fast, fully automated production of prototypes or small runs of PCBs used in medical, military, and other high-performance applications. How fast can they produce a board? Within three days, as long as the design holds up. To ensure that it does, Tempo employs a DFM analysis tool to help designers detect and overcome manufacturing problems in the pre-prototyping phase.
What types of customers benefit from automated PCB assembly?
By automating the PCB assembly process, we’re able to serve customers — typically engineers, designers and product managers — and get their prototype boards assembled and shipped quicker than other contract manufacturers (CMs), which lends itself to a wide variety of fast-growing industries that demand quick turnaround times. For example, we’re seeing this need manifest in medical technology, which comes along with strict regulatory requirements; in the aerospace industry, where the ‘New Space Race’ is pushing manufacturers to compete against one another to be first to put out revolutionary new technologies; in the automotive industry, where autonomous vehicles and new connected tech is evolving quickly; and in the industrial space, which is seeing a proliferation of new IIoT technology.
What advantages come from fully automating this process?
Through PCBA automation in our smart factory, we’re able to bridge the communication gap between the engineer and manufacturer by automating the flow of information from the engineer’s design to the machines and people on the connected factory floor in a continuous cycle of design, build, and test.
How does Tempo help engineers fine-tune their designs early in the process?
Engineers can drag-and-drop their CAD designs into our secure web portal, receive real-time design feedback, and get a quote in as little as two hours. Our software analyzes their designs before a quote is even rendered, saving both time and money while providing valuable design feedback that other PCBA CMs can’t early in the process. We’re able to provide a DFM study that can provide insight on the design early in the process and give the customer feedback on manufacturing implications, such as how design preferences will impact timeline, availability, and pricing. With that information, engineers are able to modify or optimize their designs for better end results.
What types of connectors can be handled by automated assembly?
Any SMT connector with a flat pickup surface can be placed and reflowed automatically. Any through-hole connector that can survive selective wave soldering can be soldered automatically. Only components that cannot be picked up with vacuum pressure or are incredibly heat sensitive require manual soldering.
What types of connectors can pose special challenges in the manufacturing process?
Many connectors require special processes. For some it’s just carefully chosen pick and place vacuum nozzles and computer vision analysis, for others it’s much more involved. A prime example of the latter is solder-charged terminations. These connectors require special attention in paste, to ensure sufficient paste volume is present, as well as special attention in reflow. We are hesitant to run these connectors on the first side of an assembly, as defects can be introduced running these connectors upside down during a second reflow cycle. Rework on such connectors is challenging and ill-advised. Another example is mid-mounted SMT edge connectors. These connectors often require special assembly fixtures to ensure they stay flush with the boards during reflow.
What steps of the assembly process are not automated by Tempo?
While automation ensures efficiency and accuracy across the factory floor, a great deal of value comes from human expertise, even as we look at future manufacturing processes. A level of human oversight will always be needed, particularly in situations such as quality assurance/quality control (QA/QC), which require a secondary pair of eyes and assessment. This human oversight, too, can be improved by providing perfectly curated data to each part of the process. By automatically extracting this data and presenting it to the right individual at the right moment, we are tying our employees into the digital thread that runs from the customer to the factory and back again.
How do you ensure quality control?
Quality control is conducted and ensured throughout the entire PCBA lifecycle. We only source components from industry-trusted partners and believe in data-rich automated processes during all board builds. Prior to finalizing all board builds and acquiring QA/QC sign-off, we have each board reviewed by our highly trained and specialized QC staff. We trust that our software and robotics will put the pieces together, but also recognize that there isn’t yet a replacement for QC like the trained human eye.
How does Tempo work with component makers or distributors to source products?
We have built a network of component manufacturers and distributors through trusted relationships that are digitally connected to our platform to provide real-time availability and pricing.