PCB fabrication is not always the highest cost driver for a new product's manufacturing budget. However, because of the number of design elements in a PCB, it does present many opportunities for cost reduction. Some of those opportunities may not be obvious, arising from the selection of the number of PCB layers, the type and color of the solder mask, the size of drills, the number of drill hits, and clearances in etched features. There are other elements that drive cost as well, such as milling of slots, edge plating, castellations, and much more.
In a recent conversation with Greg Pap and Drew on the Altium OnTrack podcast, Zach Peterson discussed how simple changes to a PCB can lead to big cost savings during fabrication, but without compromising the critical performance aspects of the PCB. For companies who are not experts in PCB design, as well as more important areas like EMI/EMC and SI/PI, there may be cases where the board is over-engineered in an effort to prevent problems in the aforementioned areas. Over-engineering always leads to higher costs due to greater complexity and fabrication.
Watch the clip below with Greg Papandrew or watch the full Altium OnTrack podcast episode here.
The Takeaway
As a company scales their PCB orders up to higher volume, small changes in the design present more and more opportunities for cost savings. For example a simple change in drill size on vias can produce significant savings by extending tool life. Other simple changes in areas such as materials and layer thicknesses can produce similar savings. When producing at the 100,000 per year or million per year levels, these cost savings become substantial and should be investigated once a company is transitioning to high volume PCB production.
Transcript
Greg: Basically, I've been in the industry for over 30 years. I've become one of the older guys now, and I am a PCB broker. Yes, you can use the b-word with me. I buy and sell boards from all over the world, primarily from Asia. I help customers, especially OEMs, with their design for manufacture on a circuit board and how to make that as cost-effective as possible. That's what I really bring to the table when I'm talking with OEMs and EMS companies: how to make this board less expensive.
At the same time, it's not just about making it cheaper, but less expensive. What happens is a lot of guys and gals will design a circuit board that is a Porsche—it's a great design—but do we have to have it this high-tech when a Ford will get you there just as well?
I had a customer recently who developed a project with me almost three years ago, and it came to fruition as a high runner, a monthly runner. It's practically a wearable, and they had it as a four-layer board. They said, "Greg, it needs to be a four-layer board. We want to mill it down; it needs to be 12.8 mils and really thin." They were going about it the wrong way. They also said, "It has to use this material."
I looked at them and said, "You really pigeonholed yourself. Why can't we build this as a two-layer? Why does it have to be Black4? How about black solder mask? Why this material when it doesn't go through an assembly process? You picked the most expensive material to build this board on, where 150 TG works well." They just kind of looked at me, and when it came right down to it, when I broached the subject, it's a million pieces a year. I was saving them 40 cents per board on this, and they said, "Greg, why are you pushing so much?" I said, "Well, I'll stop, but I'm giving you 400,000 reasons a year why you should redesign this board."
So, that's where I really help. I look at it and say, "Hey, do we have to have this kind of technology?" In some cases, yes, we do.