Issue link: https://iconnect007.uberflip.com/i/1514189
32 DESIGN007 MAGAZINE I JANUARY 2024 Digital twin is a term we often hear in the industry. What's your take on it? Digital twin allows a machine in the real world to predict what a machine will do to the design we have on the table in front of us. If we have it with the entire line, then we can make all the predictions for the real-world scenario before we get there. Part of the issue, though, is every piece of equipment needs to be digitally benchmarked for performance characteristics and all the data must be ready for a true digital twin, a true manufacturing environment. Right. Test is slightly easier than assembly, where you have analog-type problems like heat transfer, and tombstoning is caused because of the disproportionate amount of heat and cool- ing of parts in question. When we are testing, it's reasonably straightforward, and we can predict exactly what a particular option on a machine can achieve. With the circuit and the parallel components around the component we want to test, we know exactly what it will do. With proper circuit analysis, we can pre- dict exactly what a machine can achieve. Obvi- ously, with any analysis, we can predict that, but we might get it wrong one time. Because we have a closed-loop system, our prediction is compared against the actual real cover mea- surement. Any discrepancy is either because the debug engineer has not done a particu- larly good job, or our estimator isn't so good. Whenever we get a discrepancy, we can look at the report and say, "Here's your problem, sort it out," or, "It's our problem we will sort it out." In your software, are you looking at the entire line for the digital twin or are you limited to test? We pretty much focus on test because most of our customers require it, but we aren't limited. We do have some customers that don't require parametric optimization as their volumes are low enough. ey don't want to go to a second source for soware to do the job, so we provide assembly and inspection machine analysis and outputs for them. ere's no limit to what we can do. It's just that we focus on test because that's what our customers tend to want. That makes sense, and it ties into design for manufacturing (DFM) and design for test (DFT). When a circuit board designer looks at laying out the assembly, what should they keep in mind for DFT? Before we start laying out the board, we look at the schematic because that's where it's easier to make any changes. If we can give predictive analysis at that stage, they will save a lot of time by just changing the schematic before the lay- out starts. First, we can look at a design, component models, and connectivity, and ensure that this has been done in a way that will not limit test coverage downstream. We have several stan- dard rules that are commonly used, but users also have the ability to verify any issue against their own rule set. en we can start to look at test coverage estimation and optimization. If we take an example of ICT and boundary scan, we want to test as much of the board as possible Dean Poplett