Issue link: https://iconnect007.uberflip.com/i/1219242
MARCH 2020 I DESIGN007 MAGAZINE 51 Shaughnessy: Recently, we've asked designers if they have any idea how much each design costs and what the total cost of a design is. Some of the managers say, "We know how many hours we spent on it." You all know who your users are; do they track the average cost of a design? Griffin: That's a big thing that's hap- pening in PCB design right now. Again, it's not necessarily my area of expertise, meaning the product lifecy- cle management tools, where they're checking the work in process, and managers have a dashboard so that they can see how much time people are spending and what parts they're choosing. Are they choosing the most cost-effec- tive parts? There's a lot of tie-backs into corpo- rate databases. Look at materials. A lot of engi- neers at DesignCon will have to make tough de- cisions. If they're going to go to 5G or 11G, what materials do they need to use? Some of the costs of advanced materials are significantly more ex- pensive. Do you need those materials, or can you get by with something cheaper? That's another area where design for profit- ability comes into play: when you want to use the lowest-cost materials, but you still want to be on the leading edge because you can't be at a competitive disadvantage where your com- petitors are going twice as fast as you. Your SI expert has the expertise to look at materials and look at signal quality with a less expen- sive choice. They can make all those trade-offs and say, "I've found some ways that we could reduce the cost of this board by five bucks." They're going to produce a million of them, so that makes a big difference. Shaughnessy: Are your customers asking you specifically for more cost-aware design func- tions, or do they want more data up-front in the design process, which can wind up helping them save time and thus cut costs? Griffin: Yes. Here's another example. We have this technology called PowerTree; it's a tech- nology that we brought to market originally af- ter working with Cisco. The people who cre- ated the schematic didn't know how many de- coupling capacitors they were going to need. Thus, they would spray a bunch of decoupling capacitors down on the design and wouldn't necessarily make it easy to figure out which component the decoupling capacitors were associated with. Another big issue was that sometimes you're starting with one voltage, but then you have to break that voltage down to meet all the requirements of all the different components. Now, if you do that in any design tool and go through a filter component, what ends up hap- pening is those nets on the output of the filter may be named all by the tool, not by the de- signer. But those nets are important nets that you have to analyze if you're a PI engineer. The people at Cisco spent so much time at the end of the design identifying all of the nets they need to analyze before running PI analy- sis. We said, "Okay, let's fix this problem be- cause we have the schematic, the layout, and the analysis tools." We put this feature called PowerTree upfront. Now, at the schematic lev- el, they can trace out the source to every com- ponent that consumes power and see how the voltage is getting broken down. PowerTree provides a graphical visualiza- tion of each power path, plus it captures the names of all those internally named nets. We have all that setup information. With the Pow- erTree, anyone at any point in the design cycle can just apply the PowerTree, and everything is set up for PI analysis. You can run an analysis I-Connect007 editor Andy Shaughnessy (right) talks with Brad Griffin of Cadence.