Issue link: https://iconnect007.uberflip.com/i/1533085
Dack: Exactly. ey don't have time to get into the manufacturability of a design. ey pro- ceed upon an assumption that the designers have fulfilled their manufacturing constraints. ey say, "Here's what it will cost," and then they win the bid and let you have it with a list of issues and changes they'll need before they can start. Some are accused of using this strategy to buy time. Let's say there was a previous engineering query, and they want to know if they can go back six months and do the same thing that was already answered. We nonchalantly say, "Okay." Sometimes the supplier says, "You've sent us Gerber data that can't be manufactured. We have a 3-mil line here. You're expecting us to print an edge in two-ounce copper. It can't be done. We would like to change your design and use quarter- ounce copper. Please confirm." is is called a "form, fit, and function" question. If they build the board and it won't perform, we could be liable for millions of dollars. So, we send these types of queries off to our program manag- ers to gain approval for the change. It can take weeks, slowing down the cycle even though everybody's already approved this quote and delivery. It puts us in an awkward position. Our customers ask, "Why is the time frame chang- ing? Why is the cost changing?" Even when you work closely with your cus- tomer and fabricator, you're bound to hit sna- fus here and there. Kolar: Luckily, unless we're doing larger builds, we have direct communication with the engineer. But for a change in copper weight like that, they may have done a month of signal integrity modeling, or a lot of power integrity modeling. All of that would be thrown out the door if you make that kind of copper weight change. We'll do manufacturing for end-cus- tomer designs as well as do our own designs. So, it's always determining, "What do I want to go back to the customer on?" Dack: Oen, a cus- tomer will say, "We've been building this board with a previous supplier for a year, so why are you guys hav- ing problems?" Well, we're having problems because we're going offshore and they have different capabilities and material availabil- ity, and the customer doesn't understand that yet. is is part of the customer's learning curve. We need to help them realize the importance of understanding the capabilities offshore. But as we've talked about before, designers oen do not know where the boards are going. Maybe we should talk about the role of IPC standards, and how IPC has been evolving the standards, with the help of stakeholders around the world. Kolar: It gets tricky when you're pushing the limits or waiving IPC in parts of the board. is is oen necessary with a Class 3 board, where you might waive Class 3 around the BGA. You get into trouble with really complex designs because there's just so little room for error. We're at the edge of asking ourselves, "What can we do chemically and physically?" Dack: We oen say that the specs have trouble catching up with current technology. at's always a challenge. Kolar: It also takes more skill to keep some- thing simple. One common mistake designers make is adding more layers than they need, or they'll add microvias when they don't need them. ey'll add in laser vias. at's because MARCH 2025 I DESIGN007 MAGAZINE 13