Monthly Archives: November 2011

Productronica, Day 1

Posted on by

Initial thoughts from Productronica:

Traffic was a bit slow relative to past years. The show itself seems smaller — and again, this is relative, as it remains bigger than almost all the other major electronics assembly trade shows combined — with traditional powerhouses like Siemens, Universal Instruments and other placement companies occupying booths that, while they would still qualify as monstrous at any other show, no longer fill entire halls on their own. (This is a good thing.)

Assembleon introduced its iFlex placement line, consisting of two multifunctional (with up to eight heads each) machines and a high-speed chipshooter. The dual-lane line uses the same feeders as the A series, is well-priced for all regions and is said to be capable of 400 cph placement speeds and less than 10 defects per million.

Speaking of Assembleon, the company reupped its licensing agreement with Yamaha, which, according to CIRCUITS ASSEMBLY sources, is for one year with a one year option. We saw Scott Zerkle, the new GM of Yamaha IM America.

Other products of note on Day 1:

  • Juki introduced multiple lines and made upgrades to several others, including a new vision system (called Sentry), which combine multiple cameras in the pick-and-place head with an integrated AOI, all of which reportedly require no additional programming time. Also on display was the JX series of low-cost high-speed placement machines; the JX-200 features a high-resolution camera for vision placement.
  • Kyzen debuted  the E5321 alkaline cleaner for pallets and general maintenance.
  • Speedprint added a glue and paste dispenser to its SP 710 printer.
  • Goepel’s Opticon AOI can handle up to 32 devices under test simultaneously.

Notes:

  • Chris Fussner, whom readers will remember from TransTechnology, is setting up a US division.
  • Aqueous Technologies CEO Mike Konrad says 85% of its customers are cleaning no-clean flux.
  • News out of Bangkok is that the flooding was so bad, some factories are soaked even on their second floors. Expect a big wave of new machines to replace the thousands lost in the flood.
  • The big drop in the solar market will claim many victims. Some folks think, once all the bloodletting is over, there will be only a handful of companies left. Others aren’t so dire, but the clear consensus is that there is tremendous overcapacity in solar (estimates run north of 35%) and that it will be two to three years before demand and supply reach equilibrium again.
  • Most equipment advances seen so far are evolutionary, with incremental improvements in speed and accuracy.

 

Why DfM?

Posted on by

Design for manufacture is the practice of designing board products that can be produced in a cost-effective manner using existing manufacturing processes and equipment. — Ray Prasad

I’ve mentioned before that one of my early design gurus gave me a piece of advice that stayed with me throughout my design career. He said that after I finished a drawing or design, I should stand back and ask myself if I could build the product from the information I was providing. Well, to do that I had to know how the product would be built and the processes involved in manufacturing the product. Fortunately I was raised in a fabrication environment and had a fair knowledge of metal fabrication.

But when I started designing PCBs, I didn’t have the luxury of being around a PCB fab shop, where I could spend time with people who built the boards. I had to depend on other designers who had a wealth of knowledge about PCB fabrication.

Several years later, I worked for a couple companies that not only did design work but also had a board shop. Any time I had a question about something, I could walk over to the board shop and get some on-the-job schooling. The folks there would not only tell me what I needed to do to make the job more manufacturable, they’d walk me down the line and show me the whats and whys. I can’t help but think that this made me a better designer. I know that it gave me a better understanding of how the things that I was doing in a design affected every step and downstream process.

Over the years since I became involved in the magazine and conference side of PCBs, I’ve stressed the importance of DfM and the manufacturing process. We made it a significant part of the message and information in everything we produced, including the magazine, conferences and in later years, our websites. But DfM is still one of the major issues in the PCB design world. With the compartmentalization and outsourcing common today, it may be more difficult to get out to the board shop that builds our boards.

However, it is doable. Even when – for whatever reason – it isn’t feasible, designers and engineers need to know everything possible about board fabrication and assembly. So we keep running articles in the magazine and doing sessions at PCB West on DfM. We’re also working on some in-depth DFM courses for Printed Circuit University (PCU). In fact, we just loaded a video on PCU called Why DFM? that is available to all PCU members. (Membership is free.) In the video, Darren Hitchcock of Multek talks about some basic issues about which every designer should know. It is just a part of our effort to get every designer educated on DfM and other subjects relating to PCBs. Visit PCU today to see for yourself.

p.

REACH Database: Over 5000 Substances Registered

Posted on by

The European Chemicals Agency (ECHA) announced Wednesday that ECHA’s Dissemination Database contains now 4413 records. In total, 5181 substances have been registered as of Nov. 3, 2011, says the agency.

There are now 3908 substances published on the list of registered publishable substances.

On ECHA’s dissemination portal, you can download information or search for substances; an excellent resource for folks looking more deeply into REACH compliance.

The next big REACH deadline is May, 2013, but ECHA is asking companies to start preparing now.

En route to the 2013 deadline, there are two key deadlines for 2012:

1. Late preregistration deadline prior to the 2013 registration deadline, for first time manufacturers and importers;

2. Downstream users should notify suppliers of uses by May 31, 2012 at the latest.

The Genius of Apple’s Supply Chain

Posted on by

A massive competitive advantage for Apple is its operations function. Specifically, its supply chain operations. Apple has a regimented core business vision — built around their supply chain.

“They have a very unified strategy, and every part of their business is aligned around that strategy,” said Matthew Davis, a supply-chain analyst with Gartner (IT), who has ranked Apple as the world’s best supply chain for the last four years, as quoted by Bloomberg/BusinessWeek in a recent story on same.

It’s well known that recently Google paid $12 billion for Motorola’s cultivated, global supply chain. That fact, combined with observations about the genius of Apple’s supply chain — genius which is apparently 90% perspiration and 10% inspiration, by the way — make it clearer why a supply line could be worth so much money.

This is the world of manufacturing, procurement, and logistics in which the new chief executive officer, Tim Cook, excelled, earning him the trust of Steve Jobs. According to more than a dozen interviews with former employees, executives at suppliers, and management experts familiar with the company’s operations, Apple has built a closed ecosystem where it exerts control over nearly every piece of the supply chain, from design to retail store. Because of its volume—and its occasional ruthlessness—Apple gets big discounts on parts, manufacturing capacity, and air freight. — Adam Satariano and Peter Burrows, reporters for Bloomberg

The bottom line, according to Satariano and Burrows, is that Apple plans to double spending on its supply chain, to $7.1 billion — continuing its focus on streamlining and controlling manufacturing.

Relative to Google’s $12 billion to procure part of a new one, once again it seems to make financial sense to invest in current accounts rather than invest in new.

Excellent article on Apple’s supply chain can be found here.

Rob Heads to Guadalajara

Posted on by

As Rob sat on the airplane, he was excited to go to GDL (Guadalajara, Mexico) to help solve the voiding problem. He knew Patty would be a little peeved that he asked for Pete to come along, but she was gracious, recognizing that Rob would benefit from a success in this effort.

As the plane circled for a landing, Rob was preparing for the somewhat comical trip through customs. He always thought the red light/green light method of determining if they were going to search your bags was unusual. Oh well, go with the flow.

The ride from the airport was about 40 km to the factory through Guadalajara’s bustling traffic. After arriving at the plant Rob was relieved to see that Miguel Mendoza was there to meet him. Rob had worked with Miguel in the past and respected him as a process engineer. Miguel told them that a kickoff meeting was scheduled with the site GM, a fellow from the US named Grant Wilson.

As the meeting started, Rob introduced himself to Wilson in Spanish.

“Wow,” Wilson chuckled, “when asked if I am bilingual, trilingual or American, I have to say I am American. But, I am taking Spanish lessons.”

Rob looked at Miguel and saw him roll his eyes. But Rob thought it was at least a nice gesture that Wilson was taking Spanish lessons.

“Perhaps someone could share what actions have been taken and what the status is,” Rob suggested.

“Miguel, could you give Rob an overview of where we are?” Wilson asked.

Miguel began, “The warranty send-back rate is 5% on Droid phones. Almost all of these failures have been traced to high-powered QFNs that have significant voiding under the thermal pad. The voiding percentage is about 50-70%. About a week ago we obtained Derrick Herron, Dr. Yan Liu and Dr. Ning-Cheng Lee’s recent paper, Voiding Control at QFN Assembly, at SMTAI 2011.  We changed our stencil design, as suggested in the paper, to allow for venting of the solder paste volatiles, and voiding went down to 30 to 50%.”

“What level of voiding would be acceptable?” Rob asked.

“We’re not sure,” Miguel answered.

“So it seems we have two issues, one is to determine if 30 to 50% voiding is OK, and the other is to see if we can reduce it further,” Grant Wilson reasonably commented.

“My sense is that we need to be in the less than 30% range,” Rob added. “This may require that we use solder preforms. Voiding is caused by outgassing, but also by insufficient solder,” Rob finished.

“OK, you two go and solve the problem and get back to me. You have 3 days,” Wilson commanded.

Rob, Pete, and Miguel headed off to get started on their assignment. Rob was really glad Pete was there.  He was an expert in setting up and optimizing the component placement machines that were at this site.  Fortunately, Rob had also brought some solder preforms with him, expecting they would be required. A call to the QFN vendor confirmed that less than 30% voiding should be the target. Rob looked at the data and x-ray images of the work that Miguel and his team did to reduce the voiding by improving the venting of the flux volatiles. He was impressed, but he didn’t think it would be enough.

(Dialogue translated from Spanish)

“Miguel, I’m almost certain that we will need to use solder preforms on the two most critical QFNs,” Rob began. “There are two major reasons for voiding: The first is flux volatiles forming voids; the second is solder starvation. Most people don’t realize that solder paste is only 50% by volume metal. In cases like this, where we really need low voiding, often the only path to success is to use solder preforms to add solder metal,” he finished.

Rob then showed Miguel Seth Homer’s SMTAI 2011 paper, Minimizing Voiding in QFN Packages Using Solder Preforms. This paper describes the process steps needed to achieve a successful QFN solder preform process. Rob and Miguel spent the better part of a day setting up one assembly line to assemble with the solder preforms using this paper as a guide. They assembled 100 phones, and the voiding level was 10.5%.

Early the next morning, they met with Grant Wilson.

“By the smiles on both of your faces, I gather you were successful?” Wilson asked.
Rob went on to explain how they determined that solder preforms were needed. He explained the process and waited for questions.

“What do solder preforms cost?” Grant asked.

“They are about $0.02 (US) in quantity, but understand that your warranty cost per $200 phone is at least $10 right now (0.05 x 200),” Rob answered.

“Did you have to slow the process done?” Wilson asked. “I have been a fan of the work that you and Patty Coleman have done with The Professor, you have convinced me of the importance of throughput,” he finished.

“The Professor has pointed out that almost never is a line completely balanced. Your flexible placers were waiting four seconds for the chipshooters. We put the preforms on the flexible placer and tuned up both machines by optimizing the feeder placement. The cycle time is now 1.25 seconds faster for the 3 phone per PCB,” Rob answered.

“I’m curious, what was the greatest challenge?” Grant asked.

“Rob pointed out that the correct placement of the preform on the solder paste deposit for the heatsink part of the QFN is critical. We needed to assure that the preform was pushed into the paste far enough to leave a ring of paste around the preform to assure good mating with the QFN. We couldn’t have done this without Pete, he really knows the placement machines,” Miguel answered.

Miguel then showed Wilson an image from Seth Homer’s paper that displays this situation.
“Guys, thanks for the great work. I have to admit that I didn’t really know anything about solder preforms before today. In certain cases, it is obvious that they can be lifesavers!” Grant summed up the situation.

“To celebrate your success, I’m treating for dinner tonight at the Santo Coyote. Let’s meet there at 7 PM,” Wilson suggested.

“Thanks,” Rob, Pete, and Miguel said in unison.

Santo Coyote was Rob’s favorite restaurant in Guadalajara, but it was Patty’s too. Rob was a little sad she couldn’t join them.

Epilogue: Three months later it was confirmed that warranty send back rate was approaching zero. Miguel was promoted to senior engineer for his part in the solution to this costly problem.

Best Wishes,

Dr. Ron

Through-Hole to SMT

Posted on by

Thanks to a comment from Michael yesterday, I think everything is now cool with my Geiger counter. I had left the AT2313 default fuse setting at clock/8. That dropped the RS232 speed from 9600 to 1200 and it made the clicking sound into more of a tone, which just didn’t sound right for a Geiger counter. I still need a good radiation source though. I think I’ve picked up just a few clicks of background radiation, but that could just be wishful thinking.

Wishful thinking or not, that’s not the point. The point is that this was an example of migrating from through-hole parts to SMT. I managed to get virtually everything into SMT. The connectors, the power switch, the buzzer, batter holder and fuse clips for the tube stayed through-hole. Although I’m sure I could have all but the battery holder and fuse clips into SMT had I wanted to. I tend to keep switches and connectors that will get a lot of use as through-hole just for the extra staying power. If they aren’t used frequently, then SMT is just fine.

There are a number of things to consider when switching from thru-hole to SMT:

  1. Everything is smaller, so you can fit more in the same space or the same in less space. I took advantage of the extra board area to add in a RS232 line driver so I could connect directly to a serial port. I also added in a power-on LED.
  2. Everything is smaller so your layout is more critical. Most PCB houses will build 8mil trace and space as standard process these days. That gives you a lot of flexibility in squeezing your routing into tight areas, but it doesn’t give complete freedom. You have to be core careful because you frequently do have to route a bunch of traces into a pretty small area. When you get into the really fine pitch parts, like 0.5 or 0.4mm center to center, you have to be extra careful.
  3. Some parts are dimensioned in metric and some in SAE units. If all are one way or the other, it’s easy. But when you’ve got both, you may have to tweak with your grid spacing off and on to make sure your traces are centered in the SMT pads they connect to. It usually isn’t a horrible problem, but it can make even spacing more difficult and can make you more likely to violate a design rule.
  4. You don’t have automatic “vias” on each component leg so routing can be more difficult. You’ll likely have to spend more time tweaking the part locations and the trace routing to get a decent layout. A lot of times everything’s too close so it’s not practical to just plant a lot of vias all over.
  5. Hand soldering is less or not practical. Some people do hand solder some pretty tiny parts, but it’s not practical in more than isolated cases. If you’re a hobbyist or on a tight budget, this might limit you to through-hole or some of the largest SMT parts. For commercial work though, SMT is the way to go.

Some things to think about. But what do you get in return? Typically lower cost – especially if you want your design to go into volume manufacturing. You also get access to the newest parts that only come in SMT packages. And, many designs are space constrained, so you can cram more in while still keeping your board size down.

Duane Benson
I shot a neutrino into the air
And where it landed I already knew

 

Geiger Counter Without the Muller?

Posted on by

My Geiger counter project has been on holiday for a while. When I originally ordered all of the parts, I ordered fuse clips (to hold the tube) with solder lugs too big to fit in the holes and a trim pot (VR1) too small for the SMT pads. I moved on to other things for a while and just now got around to ordering the correct parts and soldering them in. I’ve verified that everything works except the tube. Apparently, S-13BG GM tubethe specific tube I bought (SI-3BG) is not very sensitive.

Other than not knowing if it will actually detect radiation, everything seems to work just five with Mighty Ohm’s original Atmel code. The only difference from his instructions is that the RS232 is 1200 baud instead of 9600. I’m not entirely sure why that is. The source code specifies 9600 and I have an 8MHz resonator just like his kit. I’ll worry about that later. At least it works.

It will beep if I touch my fingers to each lug of the geiger tube, but I haven’t been able to detect any naturally occurring particles. There are a couple of possibilities.

  • I had to choose a different transistor for Q1 and different diode for D1 because I couldn’t find those specific parts in SMT. Maybe the gain or some other performance spec is too far off.
  • The type of tube I bought is not sensitive enough so I just need to find a stronger radiation source.
  • I don’t have VR1 set right to give a high enough voltage to trigger the tube.

I’m going to try a 100:1 voltage divider to a unity gain current amp to measure the voltage and go on the hunt for a hotter (but still safe – I hope) radiation source. I might go back to eBay and buy a different tube too. Lastly, I’m going to get out some data sheets and look at my subs again. Maybe try to find something even closer to the original. Once I’ve verified that it all works, I’ll make the design files available as open source.

Duane Benson
If the Alpha is the tough guy, why can it be stopped by a single sheet of paper?

http://blog.screamingcircuits.com/

Killer ‘Crap’

Posted on by

Harvard historian/condescending bore Niall Ferguson claims in this interview with the Wall Street Journal that six institutions (aka “killer aps”) were responsible for the West dominating the East, and attempts to describe how that ground has shifted.

He ticks off as reasons competition, science, rule of law (private property rights), medicine, the consumer society, and work ethic, and claims the West is ignoring the massive changes coming.

Ferguson’s argument falls down in many places, however. He downplays or fails to note the myriad central issues that could slow or stop China’s rise, such as the slow, steady poisoning of its own people through blatant pollution; the double and triple redundancy in which China is building out its infrastructure capacity despite pitiful demand; the staggering (and growing) economic disparity between the haves and have-nots; the lack of a fair and vigorous legal system; the lack of a free press; its aging society (with its inherent staggering medical costs) and other obvious disadvantages. Yet understanding and adapting these “killer aps” have been just as integral to the rise of Western society.

China, as every “economic historian” should know, has undergone internal revolutions about every four decades. It is not a single, homogeneous*s society. It is a large, disparate nation full of local tribes, most of which are very wary of government. I don’t know whether Ferguson spent time watching the events in the Middle East this year, but if hs has, he knows that citizens who are systematically deprived sooner or later get royally ticked off. The pattern of history leads to democracy, which China most decidedly is not. While Ferguson takes analysts to task for not looking at the reasons behind the “collapse” of the West, he is disingenuous in not critically reviewing the shortcomings of the East.

He asserts that globalization, not Wall Street, has been the source for pain inflicted on low-income US workers, but fails to explain why that same globalization hasn’t broadly helped workers in the East. His take on work ethic is just plain silly: It suggests that the Chinese didn’t work hard in 1600-1900s, and that played into their poverty.

And his take on the perceived stability of the Soviet Union before its collapse is completely wrong – every US President starting with Truman predicted that if the US kept the pressure on, the USSR would fold under its own lousy model. And that’s exactly what happened.

Let’s consider one other aspect: The East has risen because the West poured money into it. Such resources are dynamic and can – and do – migrate. China is attractive to Western investors because of its low cost labor and potential for large consumer appetites. Western companies are not, however, emotionally invested in China. It’s simply one vehicle to wealth, and there are many other cars from which to choose.

In the end, it seems Ferguson misses the points both small and large. In trying to explain why the West beat the East during the past few centuries, he attempts to channel badly, Dr. Jared Diamond, the UCLA professor who in the 1990s dissected the same economic differences by showing why certain technology organically grew in some places and not others. If you are looking for such insight, stick with Diamond.

Thai Floods’ Hidden Asset

Posted on by

In a perverse way, the flooding in Thailand might have a hidden benefit — it could help boost pricing in a way the market otherwise would never allow.

Seagate today said as much in an SEC 8-k filing. The HDD maker noted the severity of disruption the floods have wrought on the hard drive supply chain, causing it to project total industry shipments of 110 million to 120 million units for the quarter. That’s in line with IHS iSuppli’s forecast of a 28% year-over-year drop. Better rethink gifting a  PC for Christmas.

But there quite possibly a silver lining. When capacity is reduced and demand is constant, prices rise. Deutsche Bank senior analyst Sherri Scribner said as much today, noting “Despite the significant shortfall in total available market this quarter, we believe Seagate and the industry will see a gross margin benefit from HDD supply disruptions. As we have already begun to see in the channel, limited availability of HDDs is driving prices higher and pricing is the primary driver of gross margins.”

She also points out that the effect will be lingering, as HDD pricing is set based on prior quarter prices.

We saw this a few years ago, when a fire at ASE in Taiwan took an estimated 10% of the world’s flip-chip capacity offline and pushed up prices and delivery times for several quarters.

The electronics supply chain has long been in dire need of a little inflation. This could help.

Isola’s IPO

Posted on by

Isola is going public.

No big surprise there, except for 1) it is about six years later than I would have first thought and 2) November 2011 is not exactly the peak of the IPO craze.

Although I have known Ray Sharpe, Isola’s CEO, since his days at Alpha Metals (almost two decades ago), I haven’t yet spoken to him about the decision. That said, I would guess that Isola feels the next 12 months could be rocky. The company has blown the doors off so far in 2011, and perhaps they think they should strike while that iron is hot.

Moreover, if 2012 sinks, then they might need the cash from the IPO to help cover the downturn. I can’t see TPG wanting to put more of its own capital in.

Isola was the largest laminate maker to be privately held. This is a big story.