Tips to Reduce PCB Turnaround Time for Prototype Builds
Simon Fried
As part of overall product development, creating new designs, sending them out for prototype production, testing prototype builds, and repeating this process consumes a significant amount of time, and it often requires multiple iterations. Time and costs for each prototyping run can add up quickly, and product designers need to carefully decide when to send designs out for prototyping.
In the realm of electronics manufacturing, newer designs are becoming progressively more complex with more components being placed on smaller areas. PCBs supporting new devices for use in 5G networks, military and aerospace systems, wearable electronics, and the internet of things (IoT) may require exotic materials and complicated architecture, and carry significant prototyping costs. Since the time spent waiting for manufacturers to complete a prototyping run carries both tangible and intangible costs, designers need to consider ways to reduce PCB turnaround time.
Taking a product to market starts with building a great prototype.
Decreasing Prototype PCB Turnaround Time
Keeping up with a shorter product lifecycle and maintaining a competitive edge requires decreasing the turnaround time associated with traditional PCB manufacturing processes. There are some simple strategies that ultimately reduce costs and decrease time to market for new products.
Implement Design for Manufacturing
The idea in PCB design for manufacturing (DFM) is to address manufacturability during the design stage. If a board is not manufacturable, a manufacturer may attempt their own redesign, or they will send it back to you to redesign. Paying attention to your manufacturer’s capabilities, limitations, and documentation requirements during the design phase can eliminate these potential redesigns. It is best to consult with your manufacturer during the layout phase to ensure manufacturability.
Placing fiducial markers are also very important as they are used to automate pick-and-place machines. If you do not place fiducial markers yourself, your manufacturer will have to do this for you. In some cases, this might require moving components from certain locations to make room for fiducial markers.
Provide a Complete Documentation Package
Manufacturers require a full documentation package that generally includes Gerber files, drill files, a complete bill of materials, a netlist file, your raw CAD files, centroid data, assembly instructions, and assembly drawings. Neglecting to send centroid data is one common cause of delay as this data specifies component orientation and links each component to its reference designator. Your manufacturer will need to figure this out on their own, or they will have to contact you to provide this important information.
Source Components Yourself
A common cause of delay in PCB manufacturing and assembly occurs when one or more required components run out of stock between the time the bill of materials was created and the time the fabrication order was placed. Careful planning and sourcing will ensure that your orders can be filled by a major distributor. This can eliminate months-long lead times that arise due to changes in the component supply chain.
Instead of relying on your manufacturer to source your components, you could take the initiative and source them on your own. While a manufacturer may have good relationships with component distributors, large manufacturers and rapid prototyping houses are vulnerable to component shortages and even counterfeit components. If a particular component is not available and your manufacturer takes the liberty of redesigning your board around a replacement, there is no guarantee that they will implement a redesign correctly. Both problems increase PCB turnaround times and put you at risk of receiving defective products. There can also a concern with keeping the intellectual property of your design secure when sending it to a third party.
Simplify Your Designs
Two-layer PCBs are about as simple as you can get. These boards will require a small number of pressing, plating, etching, and coverlay steps, and generally have quick turnaround time. Unfortunately, most modern boards are multilayer PCBs, which require numerous fabrication steps for each layer. Reducing your layer count to the greatest extent possible will eliminate unnecessary fabrication steps, ultimately decreasing PCB turnaround time.
Reducing layer counts in complex multilayer PCBs ultimately requires removing through-hole vias in favor of blind and buried vias. Creative layer stack design and routing can eliminate some necessary layers. The tradeoff is that more plating steps will be required with these vias, providing only a marginal reduction in the number of fabrication steps.
How Additive Manufacturing Helps Reduce PCB Turnaround Time
While the above tips are useful for traditional manufacturing processes, there is an even more effective way to reduce PCB turnaround time without constraining your design—additive manufacturing. Compared to traditional PCB manufacturing, the layer-by-layer 3D printing process in additive manufacturing eliminates dozens of fabrication and assembly steps. This brings manufacturing time for complex PCBs down to a matter of hours, compared to days or even weeks with traditional PCB manufacturing processes.
These digital manufacturing systems require little to no operator involvement in the manufacturing process. Finally, you won’t have to order some minimum amount of boards in a prototyping run. You’ll be able to quickly produce a single board or multiple variants in parallel with the right additive manufacturing system.
There are plenty of other advantages to using an additive manufacturing system for PCB prototyping. Designers that want some guarantee their PCB can be properly manufactured are constrained by traditional manufacturing processes, which limits their design freedom to the traditional trace and via architecture in multilayer PCBs. An additive manufacturing system allows printing of conductive structures and dielectric substrate in nearly any geometry, releasing designers from the confinements of planar geometry. New design won’t be limited in terms of form factor or geometry.
Keeping additive manufacturing capabilities in-house is also beneficial from an IP security and QA standpoint. Sending unique designs to an overseas manufacturer creates a real risk of IP theft. Design data can be easily stolen and replicated by unscrupulous manufacturers, ultimately harming your bottom line. You’ll also have to rely on your manufacturer to ensure quality and sourcing, both of which are critical contributors to manufacturing yield, lead time, and costs.
Keeping rapid prototyping capabilities for electronics manufacturing in-house allows you to take advantage of all these strategies to reduce PCB turnaround time. With the DragonFly additive manufacturing system, you can quickly manufacture prototypes in house with significantly reduced lead time compared to traditional processes. Read a case study or contact us today if you’re interested in learning more about the DragonFly system.
A co-founder of Nano Dimension, Simon Fried leads Nano Dimension’s USA activities and marketing for this revolutionary additive technology. With experience working in the US, Israel, and throughout Europe, he has held senior and advisory roles in start-ups in the solar power, medical device, and marketing sectors. Previously, Simon worked as a consultant on projects covering sales, marketing, and strategy across the automotive, financial, retail, FMCG, pharmaceutical, and telecom industries. He also worked at Oxford University researching investor and consumer risk and decision making.