Robots and the Law

In the April issue of PCD&F/CIRCUITS ASSEMBLY, I wrote about the need for a balance between autonomous machinery and human-operation equipment. I wrote the piece in the aftermath of the Malaysia Airlines Flight 370 disappearance, and referenced, among other things, the Toyota sudden unintended acceleration problems and the self-driving cars that are beginning to appear on US streets.

Seems I’m not the only one working their way through this. On May 5, a pair of researchers at the Brookings Institution began a series of papers (The Robots Are Coming: The Project On Civilian Robotics) that considers the legal ramifications of driverless cars.

That led me to Google, which uncovered a few more references to potential tort roadblocks.

While my work considered the technical and emotional issues that always factor into to any major technology shift, the legal aspects are equally in play here. For those interested in the subject, the Brookings Institution project is especially worth a read.

 

 

 

 

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PCB Panel Routing Technique

Most PCBs we receive are individually routed; i.e., not panelized. That doesn’t mean that, sometimes, sending them in a panel isn’t a good idea, or required. Generally, we don’t require panels (sometimes called a pallet), but there are some cases when we do.

V-score panelIf the individual PCB destined for Full Proto service is smaller than 0.75″ x 0.75″, it needs to be panelized. If a PCB needing Short Run production service is less than 16 sq. in., it needs to be in a panel of at least 16 square inches to qualify for Short Run.

So, you ask, why else might I want to panelize my PCBs? Keep reading and I’ll tell you why.

  • First, if you’ve got a lot of small boards, it’s easier to handle and protect then when they’re in a panel. A few panels can be more safely packed coming and going from our shop here.
  • You may be able to get the through our factory faster. If you have a really large number, and need them super fast, panelizing them may enable that fast turn. With a lot of boards, sometimes, it simply isn’t physically possible to put them all on the machine, run them and take them off, in a short turn time. Panelize them and the machine will be running longer for each board change, which reduces the total run time.
  • It may also cost you less. If you use leadless parts like BGAs, QFNs or LGAs, you can usually reduce your cost a bit by panelizing the boards. Leadless parts cost a little extra because of the X-Ray test needed, but the extra handling is mostly per board, rather than per part. One panel of ten boards with ten BGA, in total, will cost a little less than ten individual boards with one BGA each.

Stay tuned for my next few posts where I’ll cover the pluses and minuses of different panelization techniques.

Duane Benson
I looked outside my window and what do you think I saw?
The strangest sight I’ve ever seen you’ll never guess just what I mean,
I can’t believe it myself

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Weibull Analysis at Ivy U

Folks,

Let’s check in on how Patty is doing at Ivy U.

Patty was nearing the end of her teaching stint at Ivy U. Only a few more classes remained. She had to admit that she was sad to see this adventure end. Oh, well, such is life.

The syllabus allowed for the last few lectures to cover “Selected Topics,” so Patty decided that her selected topics would be Weibull Analysis. She felt passionately that all engineers should have some exposure to failure analysis and this topic fit right in to engineering statistics.

Before she knew it, she was heading north up to Ivy U for her next-to-the-last lecture. She thought she should soak in the beauty of the campus as her car approached, for soon this would be her last time at Ivy U for a while. Today she was lucky, she found a parking spot right away.

As she walked into the main engineering building, she noticed a note in her mailbox. It was from Dean Howard. She quickly opened it. He was requesting a brief meeting after her last class.

“Yikes!” thought Patty, “Dean Howard wants to see me! I wonder if it’s serious. Did I goof up, somehow?”

She would have to wait for two days to find out what the Dean wanted and she couldn’t worry about it now, as her class was starting in 10 minutes.

Patty began the class by explaining the development of Weibull’s theory and gave a few examples. She showed where the scale factor and slope came from. Patty emphasized that a steep slope indicted a tight distribution of data (a good thing for prediction from the data) and that a larger scale suggested a longer mean life. She then discussed the importance of different types of tests in electronics, such as thermal cycle testing and drop shock testing. As an example, she thought she would share some accelerated thermal cycle data for two different alloys that are used in electronics assembly.

She showed the first set of data in a PowerPoint slide (Figure 1).

“Can someone explain these results to me?” Patty asked.

After some murmuring, Karen Armstrong raised her hand.

“Yes, Karen,” Patty responded.

“It appears that Alloy 2 demonstrated superior performance, as seen in its much steeper slope and slightly better scale,” Karen answered.

“Nice job, Karen,” Patty responded.

“What about this one point?” Patty asked as she pointed to the obvious outlier for Alloy 1.

There was more murmuring, but no one raise their hand. So Patty showed a slide with the outlier removed.

“I have removed the outlier because failure analysis showed it was atypical,” Patty said.

“As you can see, now alloy 1 has a slightly better slope. This suggested a tighter distribution and hence more ability to predict performance,” she went on.

There was now very loud murmuring, finally Scott Bryzinski raised his hand.

“Yes, Scott?” Patty responded.

“Professor, it just seems like cheating, dropping a bad data point because you claim it is not representative of the other samples,” Scott explained.

There were many loud echoes of agreement.

Patty chuckled a little.

“OK, OK, you are right. It is not fair to censor a data point in most cases. This is part of the lesson of this class. Don’t censor data lightly,” Patty said.

“Let’s look at data for Alloy 3 and 4,” Patty went on.

The students looked at the data for some time and finally Diane Pompey raised her hand.

“Yes, Diane,” Patty acknowledged.

“They look about as dead even as one could expect, except that the sample sizes are different. Alloy 3 has 15 samples and Alloy 4 only 13 samples, as can be seen in column ‘F’ in the ‘Table of Statistics’,” Diane explained.

“Nice work Diane, few people would have picked up on that difference,” Patty replied.

“I will tell you that both alloy 3 and 4 had 15 samples to start with in the test. What do you think happened?” asked Patty.

Very quickly, Fred Wilkins raised his hand. Patty nodded to him.

“I’ll bet that two of the samples from alloy 4 did not fail,” Fred suggested.

“Correct!” Patty responded enthusiastically.

“I want you all to take a few minutes to discuss this situation with those seated around you. I then want you to vote anonymously whether the two samples that did not fail make alloy 4 the same, better or worse than alloy 3,” Patty instructed.

After five minutes of noisy discourse, the students voted on a website, the results of which Patty could show on her laptop and project to the class. Twelve students thought the alloys were still the same. 24 thought alloy 4 was better, and 6 thought alloy 4 was worse.

“Any comments on the results?” Patty asked.

There were no takers.

“Let’s assume that the two samples that failed were tested for a much longer time and they finally failed at some very high number of cycles, say 2,000. Let’s look at what the Weibull plot would look like,” Patty said.

She then showed Figure 4.

“Can anyone explain it?” Patty asked.

After a short time, Young Koh raided his hand.

“Dr. Coleman, the added cycles increased the scale significantly, but ruined the slope, suggesting much more scatter in the data. As you suggested earlier, reliability testing is about hoping to have the ability to predict lifetime. With the large decrease in the slope, prediction becomes much more difficult, So, sample 4 is likely worse than sample 3, even though it has a large scale.” Young expounded.

“Precisely,” Patty answered.

“It is interesting to note that many engineers in the electronics industry today just ignore the samples that don’t fail,” Patty went on.

The class looked at her with shocked faces.

“Well, that’s all until next time,” Patty said.

“Two of the female students, Jessica Han and Mary Connor, stayed after the class to talk to Patty.

“Professor, there is a rumor that you will be teaching “Manufacutring Processes” next term, is it true?” Mary asked. Then went on, “We really hope so. You are best teacher here.”

Patty was so touched she started getting a little misty eyed, “Thank you for your kind comment, but I doubt that that will be the case,” she said as her voice quavered.

Will the Dean fire Patty or will she be teaching Manufacturing Processes the next term. Stay tuned to see.

Cheers,

Dr. Ron

 

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Could Foxconn Deal Bite Apple?

The notion that Foxconn might take a large stake in a major Taiwanese telecom equipment company poses a litany of interesting questions for its largest customer — Apple.

For example, Foxconn, which gets 40% of its revenue from Apple, could now be in position to become both a major Apple supplier and a major enabler, since millions of iPhones and iPads would conceivably be connected via Asia Pacific Telecom’s network. What influence could Foxconn thus have over Apple’s ability to operate in key Southeast Asia markets? Would it possibly seek to leverage that network by negotiating with Samsung to force better pricing from Apple? Will other major EMS/ODMs that play heavily in this space (Jabil, Pegatron, Compal, Wistron) follow Foxconn’s lead?

The EMS/ODM model continues to evolve. Foxconn seems intent on speeding that evolution ever faster.

 

 

 

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SEC Upholds Conflict Minerals Reporting Deadline

US Securities and Exchange (SEC) Commission Chair Mary Jo White on April 29 said that the agency will continue to implement the conflict minerals rule upheld by the US Court of Appeals.

The SEC has also issued guidance on meeting the May 31 reporting deadline. The gist is that companies must meet the deadline as expected, but may omit aspectsstruck down recently by the US Court of Appeals.

SEC Division of Corporation Finance Director Keith Higgins said companies should comply with parts of the rule that the court upheld and file initial reports by June 2 (reports will be due on June 2, 2014 as the May 31 deadline falls on a Saturday). Thing is, most parts of the rule were upheld, so there is very little change to requirements on the whole.

Higgins said no company will be required to describe products as “not been found to be ‘DRC conflict free’” but companies will still have to disclose the origins of the products.

Legal outlook.Insiders at IPC say that yesterday the industry petitioners, led by the National Association of Manufacturers, filed a Motion for a Stay with the SEC in the conflict minerals case. If the SEC denies the stay, the petitioners will consider filing a stay request with the DC Circuit.

On April 14, U.S. Court of Appeals for the District of Columbia Circuit ruled that the requirement that firms report whether their products have “not been found to be ‘DRC conflict free,’ included in the SEC conflict minerals regulation, violates the First Amendment.

If there is no stay requested or granted, and the case is remanded to the district court, that court may simply remand to the SEC to implement the DC Circuit’s decision in the first instance.

Do I have to file? So it’s business as usual for conflict mineral compliance. And the deadline at the end of May approacheth.

There are two categories of companies who must report.

  1. The first is standard: a company that uses minerals including tantalum, tin, gold or tungsten if that company a)files reports with the SEC under the Exchange Act, b) the minerals are “necessary to the functionality or production” of a product manufactured or contracted to be manufactured by the company. For more on this, visit this helpful FAQ.
  2. The second category of company that must report is a softer definition, for these are companies whose downstream customers demand information on raw materials so that the downstream company can then file with the SEC. So, even though your company may not have to file with the SEC, if you’re a supplier to a company that does, then you’ll have to report to them on your conflict mineral uses. Yes, it will be challenging. But it’s not impossible.
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Component Packages — Let’s Get Small

I’ve been on a bit of a package binge lately. First talking about metric vs. US passive sizes, and then a very tiny ARM Cortex M0 from Freescale.

The Freescale BGA part checks in at 1.6 x 2mm. That’s cool and I’m almost always in favor of making things as small as possible, but, as I wrote in my prior blog on the subject, it’s not always possible. The 0.4mm pitch BGA is problematic unless you can spend a lot of money on the raw PCBs, or will have super high volume.

All is not lost, though. You still can use a tiny ARM Cortex M0 part. Just not quite as tiny. That same part also comes in a 3 x 3mm QFN package. You lose four pins (16 vs. 20) going from the BGA to the QFN, but if you can handle that, it’s a very viable option that doesn’t require any exotic circuit board technologies.

A few years ago QFNs were scary, but not so much any more. I’ve designed a few of them in using Eagle CAD. Just be sure to pay attention to the footprint. A 6 mil trace is more than small enough for a 0.5mm pitch QFN.

Duane Benson
Strive at all times to bend, fold, spindle and mutilate

http://blog.screamingcircuits.com/

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‘Patty’ in the Real World

Folks,

Every year, the wonderful folks at PCM host a visit from my class on manufacturing processes and provide a real-world tour of an electronics assembly facility. Our relationship has resulted in the class producing a video on electronics assembly. In addition, several class projects have been performed at PCM over the years; projects that have helped my students learn and have, hopefully, helped PCM’s operation.

A few weeks ago it was time for this year’s student visit. Rob Steele and Jon Scheiner were our hosts. During the tour, Rob mentioned that he and the PCM team have implemented many of the productivity concepts discussed in The Adventures of Patty and the Professor. Rob even mentioned that he thought the book, at some level, was a “page turner.” It is personally rewarding to see people benefiting from this book.

Anyway it is very clear from our tour that productivity is high at PCM. It is my hope that others might also benefit from the stories in The Adventures of Patty and the Professor. If you have benefited from the book, please let me know.

Cheers,

Dr. Ron

 

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Bypassing 2.5D

Did Nvidia’s announcement that it would use 3D packaging with silicon-through-vias on some forthcoming Pascal graphics processors to make more memory available with minimal delays signal the start of a general acceptance of stacked memory chips?

IPC Apex Expo was the best in many years. Attendance was good, both in the conference as well as on the show floor. Even Thursday morning saw potential buyers visiting exhibitors in their booths. Capital equipment buyers were twice as optimistic as in the prior year — about 65% stated that they planned to buy equipment this year versus about 30% last year. Exhibitors stated that they were making sales and getting commitments for future trials in their booths during the show — event though there was little in the way of new systems to be seen in the hall. One independent equipment sales rep stated that he had more customer meetings at this show than at the five previous events combined.

New product introductions and improvements abounded. EarthOne Circuit Technologies Corporation (dba eSurface Technologies) created quite a stir with its sponsorship of the Tuesday luncheon to announce its new additive printed circuit board process.

Six OEMs responded to the IPC’s effort to get them more engaged at the management level. The Ambassador Council held its first meeting to explore how it could provide help to further the knowledge and success of IPC members. The executive management meetings’ programs were excellent but still failed to bring in more than a handful of bare board fabricators. Counterfeit components was one of the hot topics throughout the event.

On the other hand, a number of historic names (Christopher Associates, Multiline) were missing from the show — victims of the business conditions and America’s continual decline in the bare board market as well as direct incursions by foreign capital equipment producers. Some exhibitors were still introducing their “new” systems and processes after three or more years of failing to gain traction. However, it warmed my heart to see the resurrected Dynachem name and logo back in America in Osvaldo Novello’s booth, Automatic Lamination Technologies S.R.L.

The IPC event has appeared to have morphed into an analog of the old Nepcon West in terms of massive entertainment activities. The major corporate exhibitors not only took large booths but also used to arrange major hospitality events, receptions, and cruises which captured many of the show attendees. They spent hundreds of thousands of dollars at Nepcon. This put the smaller exhibitors at a distinct disadvantage.

When the IPC established its first trade show it decided to level the playing field a bit for the smaller exhibiting members. It banned major hospitality events during the show that would take attendees away from the event. Some companies that violated this rule were even penalized by having their chance to select the following year’s booth moved to the last position. The IPC arranged for cruises (in San Diego). It produced major galas with music, food, entertainment, and other activities. It solicited sponsors — who received credit for their participation. The price for admission to the event was reasonable. Many companies bought tickets for their customers. It was a great night for all.

But, things have reverted. Companies with deep pockets have already started to reserve ballrooms, night clubs, and to plan other major events for IPC Apex Expo 2015. I do not think that this is a good trend.

Bob Black of Juki Automation said that sales closed during the first two days of the show actually “more than paid” for the show. He said that although January was a bit slow, February sales were strong and he expected March to also be a good month.

Chris Fussner of Yamaha (TransTech) stated that he expected a good year in 2014 as his American distributor organization achieved a positive cash flow in second year (2013).

Don Walsh stated that Ueymura had a record year and a strong start in 2014.

Nihon Superior’s Tetsuro Nishimura said that his booth was busy throughout the show and that he was glad that he came. He’ll be back next year to exhibit with the IPC for the 15th time.

OMG’s Mike Carano (admitted to the IPC’s Raymond E. Pritchard Hall of Fame, the IPC’s highest honor, during the awards luncheon) stated that his company has now captured a 30% share of the North American market for its products.

Dr. Bill Elder introduced Maskless Lithography’s (MLI’s) direct imaging system for liquid photoimageable solder masks (LPISM).

Crunch time

Early reports from the CPCA show state that it is a “disaster.” One of the major exhibitors said that no one came to their booth on Day 1, and only a dozen or so – but no buyers – on the second day. Another stated that Day 1 was awful and that Day 2 was a bit better, it was just terrible in terms of attendance. Semicon China held in Shanghai at the same time was reported to also have experienced the same malaise — a dearth of customers, prospects or visitors of any type.

Can the international uncertainty be the cause? Can the economic woes and diplomatic strife in the world be the reason? Could the international cultural differences and distrust as shown through the investigations of the disappearance of Malaysian Airlines flight 370 be at fault? Are the rapid changes in the electronics industry coupled with continued closures and consolidations be the reason? Could it be that potential buyers are tired of sending armies of their troops to exhibits to see much of “the same old stuff?”

Do these events need to change for today’s and tomorrow’s technology, markets and products? Is the gravitation of business to fewer larger enterprises at fault? If so, how? We believe that ALL of these — and more — are at fault. At the same time, we note that technical conferences, which do not need to draw volumes of visitors to consider them successful, generally continue to attract members of their particular buying public.

 

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Sample Size is Important in Weibull Analysis Too

Some time ago I posted on “The Curse of the Early First Fail” and “Interpreting Weibull Plots.” Both of these posts related to using Weibull analysis to make sound engineering decisions.

Recently, a reader asked if sample size is important in Weibull analysis. It is interesting that few who do Weibull analyses discuss the effect of sample size. So, let’s do it now. Consider Figure 1. This figure shows Weibull analysis used to compare cycles to fail for Alloy 1 and Alloy 2. Considering that the slope of each curve is about the same, most people would say that since the scale for Alloy 2 is greater (1320 versus 1172), Alloy 2 is superior. But, is the difference statistically significant? By using a simple Two Sample t Test, we can analyze the data and find that there is only a 62% confidence that Alloy 2 is better than Allot 1. Flipping a coin gives us 50% confidence, so this result is not encouraging. Four samples is seldom enough to make a confident engineering decision.


Figure 1. A Weibull plot of Alloy 1 and 2 with only four samples.

If we perform the experiment again with 20 samples, we get the Weibull analysis as shown in Figure 2. Note that although the scale parameters have not changed too much, the shape parameters have changed significantly. The original 4 sample test is just not enough to really lock in on the real shape numbers for the samples. By also performing a two sample t test on the 20 sample data, we now find we have a 99.6% confidence that Alloy 2 is superior to Alloy 1. So, with 20 samples we can confidently say that Alloy 2 is superior to Alloy 1.

 


Figure 2. A Weibull plot of alloys 1 and 2 with 20 samples.

What is the minimum sample size for your test to be confident in the result? It can vary quite a bit and only by analyzing the data with a t test, after the experiment, can you know for sure. But my experience would suggest that you should never have less than 10 samples, and preferably 15 or more.

Cheers,

Dr. Ron

 

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A ‘Worthington’ Idea

EMS firm Worthington Assembly last week announced a deal to market its EMS services via CircuitHub.

WAI is a small EMS company located in Western Massachusetts. Like many in the sub-$20 million space, WAI’s owners double as its salesmen, and the firm relies heavily on word of mouth (and engineers changing jobs) for prospecting.

CircuitHub developed a universal parts library and is offering that, along with BoM, bare board and assembly quoting. PCD&F did a piece on the company last year.

Chris Denney, WAI’s CTO (and a sometime CIRCUITS ASSEMBLY columnist) explains the partnership here.

Clearly, more opportunities to order boards from a variety of suppliers via a single website are popping up, with the site typically offering free software in order to gain visitors (FabStream, for example, offers use of a PCB CAD tool capable of up to 12 layer boards, and SnapEDA offers simulation).

I would not anticipate larger EMS firms would go this route. But for smaller ones, whose cost of sales would be proportionally high relative to its income if it employed direct outside sales, using app-based vendors could be a creative and low-cost way to find new customers.

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