Prevent mistakes during production by applying early supplier involvement

Is there a 'best testing strategy'? According to Steven Van Hout, Test Engineering Manager at VDL TBP Electronics, well. According to him, the 'secret' is to be involved in the design of a new product as early as possible, preferably before the first sketches have been made. During the Test & Measure seminar, part of the World of Technology & Science 2022 on September 28 in the Jaarbeurs Utrecht, Van Hout explains his way of working and reveals step-by-step the working method of this effective test strategy.

“The crux is to be actively present as a discussion partner during the first discussions about a new product,” Van Hout explains. “We see that in practice designerAt the start of a project, people are mainly concerned with functionalities and sometimes lose sight of feasibility. Then there is a beautiful design that cannot be made or tested. If this has to be corrected at a later stage, it costs time and money and is frustrating for the customer. That is why it is so important to get involved in 'phase 0' to go through and analyze the functionalities.”

Think along

Van Hout looks at three elements in phase 0: design for manufacturing (DfM), design for testing (DfT) and Design for Logistics (DfL). “At DfM we look at the manufacturability of a product, at DfT at testability and at DfL we analyze the availability and lifespan of components,” Van Hout explains. “A report will be available from the DfL analysis in which we indicate the lifespan of the important components. Suppose the customer wants to manufacture a product for ten years, but certain components in that product have an expected lifespan of five years. We then have to make a new choice during the design process, unless we know that a design change will occur within a few years because the component is no longer available,” Van Hout explains.

Further in the process

“In the next phase, we call this 'phase 1', we are already a bit further along in the process. The electronic schematic is ready and some components have already been placed on the layout. We are looking at the DfM and DfT again, but the focus is now on the testing options. For example, we investigate whether the PCBs can be easily installed and soldered and whether there is sufficient test access. The different functionalities of it board must be easily accessible with test equipment, otherwise it will be difficult to perform measurements. In terms of manufacturability, we check whether we can place and solder all components properly. Finally, we analyze the different ones footprints of the PCBs; that are the pads on a board on which a component is placed. This way we know exactly how to make a footprint must designing to be able to solder as reliably as possible.”

Dotting the i's

Once the design is completely finished, the final finishing touches are added. “Phase 2 is the most practical phase. We carry out a final analysis in which we also check whether the recommendations from the first phase have been included design. It design for manufacturing plays a major role in this phase, so we specifically look at the technology and manufacturability of the PCBs. For example, we investigate which suppliers we can order PCBs from and whether we can do it board can fully assemble and solder in the way the customer expects from us,” says Van Hout.

Slip through

“This analysis produces a number,” the test engineer continues. “This productionyieldnumber indicates in advance what percentage of PCBs will correctly pass through the production process. During the DfT analysis we determine which 100% components are testable. There is always a small percentage of components that we cannot fully test with the instruments at hand. We call this the slip through. The customer receives a list of slip through-components and then determines, together with us, what possible solutions are available. Is the available measuring equipment sufficient, or do we need to purchase new test equipment? If we cannot find a suitable test device on the market, or if testing only needs to be done once, we will develop a test device ourselves. We have the expertise for this in-house,” Van Hout explains.

Right first time

The big advantage of this method, according to Van Hout, is the percentage right first time of the PCBs skyrockets. “The customer receives more reliable PCBs and fewer repairs, which reduces the unit price per unit board is lower. The product therefore becomes cheaper for the customer because it is complete design for manufacturingprocess and he gets more boards who are reliable in the field.”

Van Hout continues: “In the field of testability, our aim is to achieve the highest possible test score. We want the components we put on it board places, can measure properly. This has the advantage that we quickly find PCBs that contain errors and we can deliver a very high delivery percentage to the customer. So he won't do much boarding get ones that don't work. Because PCBs are always built in somewhere, it is extra important that the boarding function well. This saves the customer a lot of time and money in the long run. In addition, there is the social component: as one board for example, failure in a medical application could cost lives. Testing and measuring entails a great responsibility.”

More information?

Steven Van Hout will speak on September 28 during the Test & Measure seminar at the WoTS, from 1:00 PM to 5:00 PM in the Jaarbeurs in Utrecht. Van Hout will kick off the rush hour at 1 p.m. and after that six test and measurement specialists give a presentation. Entry is free, but you must register register in advance.