Printed Circuit & Design Fab Circuits Assembly Logo
September 2019
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september 2019 • VOL. 36 • NO. 9
First Person
6
Spinning in circles.
Mike Buetow

Money Matters
16
A lesson in lean training.
Peter Bigelow

18
Shake that distributor!
Greg Papandrew

Tech Talk
20
Prepping the data for assembly.
EMA Design Automation

24
Calculating trace length from time delay values.
Lance Wang

26
The impact of glass styles on precipitating or mitigating skew.
Bill Hargin

34
Reliability implications of self-driving vehicles.
Alun Morgan

52
Voiding under QFNs.
David Bernard

55
Trade show sociology.
Robert Boguski

58
An unusual solution for odd-form part inspection.
Gerardo Ruelas

59
Avoiding 01005 termination lift.
Bob Willis

september 2019 • VOL. 36 • NO. 9
Features
35
Nti-100
A record number of fabricators topped $100 million in sales in 2018. And after years of taking a backseat to mobile device fabs, multilayer manufacturers stand to reap the rewards.
by Dr. Hayao Nakahara

44
prototron circuits
Sometimes two are better than one. In this case, it’s Prototron Circuits’ two West Coast-based quickturn plants.
by Chelsey drysdale

47
iNEMI roadmap
A common misconception is that eco-design adds costs to products. In fact, nearly every eco-design principle reduces product costs. The first of an occasional series by the authors of the 2019 iNEMI Roadmap.
by Pamela J. Gordon

49
PCB Cleaning
Contact cleaners are widely used in the industry due to ease of use and convenience. What attributes make them effective?
by Emily Peck

IN the Digital Edition
 
The latest happenings among the IPC Designers Council chapters.
by Stephan Chavez

ON PCB CHAT (pcbchat.com)

 
Designer Training
by MIKE CREEDEN
 
Conformal Coating
by PHIL KINNER
 
A Novel Recyclable PCB Substrate
by JACK HERRING
 
Non-Assembly Cleaning Requirements
by MANUEL SCHÖLLIG
Departments
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Caveat Collector
Mike Buetow
mike
buetow
editor-
in-chief
Circular Economy Regs Make My Head Spin
M

any “topical” conferences are not just good at answering questions, but they also open one’s eyes to questions that have yet to be resolved.

The ITI/IPC 2019 Conference on Emerging & Critical Environmental Product Requirements is a perfect example. The two organizations caravanned across the US in June, bringing scores of environmentally conscious engineers and compliance officers up to date on the latest REACH and related regulations in the EU, UK and Asia.

What distinguishes REACH from almost any chemical safety regulation I can think of – including RoHS – is parties need to prove the safety of a substance before it’s allowed on the market, and exemptions must be justified from both a risk point-of-view and a socio-economic point-of-view. Multiple independent technical committees, appointed by the Member States, make those assessments.

Around the World
PCD&F People

Chin Poon appointed SL Huang president.

Insulectro named Geraldine Arseneau product manager-drill and business manager-Canada.

Ralph Morrison, author of a dozen books electronics engineering, passed away Aug. 2. He spent more than 50 years in the electronics industry and taught thousands of engineers about the fundamentals of voltage and currents.

TTM named Dan Tozer frontend engineering manager.

PCD&F Briefs

Amitron installed a MicroCraft E8M6151 flying probe tester at its facility in Chicago.

AT&S is investing 1 billion euros in a new plant in Chongqing in Southwest China.

Around the World
Edited by Mike Buetow
Bipartisan Legislation Introduced to Guard Against Foreign Threats to US Supply Chains
WASHINGTON Citing the vital need for a secure US industrial base, US Senators Mike Crapo (R-ID) and Mark Warner (D-VA) have introduced bipartisan legislation to guard against attempts by the People’s Republic of China and others to undermine US national security by exploiting and penetrating US supply chains.

The Manufacturing, Investment, and Controls Review for Computer Hardware, Intellectual Property and Supply (MicroChips) Act (S. 2316) would develop a national strategy to assess and prevent risks to critical US technologies.

“Actions by the People’s Republic of China have contributed to an unfair and unsafe advantage in its technological race against the United States,” said Sen. Crapo. “Through government investments and subsidies, as well as intellectual property theft of companies like Idaho’s Micron, China aims to dominate a $1.5 trillion electronics industry, which creates serious, far-reaching threats to the supply chains that support the US government and military. The MicroChips Act would create a coordinated whole-of-government approach to identify and prevent these efforts and others aimed at undermining or interrupting the timely and secure provision of dual-use technologies vital to our national security.”

Around the World
CA People
Curt Williams
ACC Electronix promoted Curt Williams to president. Williams has 19 years’ experience in EMS and was vice president of sales.
Rob Crawford
Benchmark Electronics named Rob Crawford hief revenue officer. He was vice president, global sales, Advanced Technology Solutions at Celestica, and previously held various leadership roles at QLogic, Quantum and Dell.
Michael Tidwell
Data I/O named Michael Tidwell vice president of marketing and business development. He was previously head of marketing and business development at Sansa Security.
Dynamic EMS hired Nicola Laird for its purchasing department.
Collin Whalen
Inventec Performance Chemicals announced Collin Whalen as Northeast US regional sales manager.
Keysight named Stacy Johnson university program manager.

Lockheed Martin named Kantesh Doss senior member engineering staff.

Bhawnesh Mathur
Masterwork Electronics appointed Bhawnesh Mathur CEO. He was most recently president and CEO of Creation Technologies, and also was CEO of EPIC Technologies, EVP global supply chain at Sanmina-SCI, and chief supply chain officer at Arrow Electronics.
Around the World
Good Chemistry: Atotech Acquires J-KEM
BERLIN Atotech has acquired J-KEM International, a supplier of chemistries and processes for the printed circuit board and metal finishing industries. Terms of the transaction, which closed Aug. 1, were not disclosed.

Rosersberg, Sweden-based J-KEM’s technology and customer relationships complement Atotech’s product portfolio and will help expand addressable markets and drive future growth, Atotech said in a statement.

Atotech will maintain all existing services of J-KEM, while the latter’s customers gain full access to Atotech’s regional and global product development, production and technical support capabilities, including its material science and analytical services.

“We are thrilled to add J-KEM’s strong products and technologies to Atotech,” said Geoff Wild, chief executive, Atotech. “We see substantial opportunities to further grow our business with this set of new and excellent products. J-KEM brings a graphite process that gives superior performance, an accelerator-free system in collaboration with an EDTA electroless copper process, as well as a palladium-based direct metallization process. These additional capabilities will help expand our reach into exciting growth markets like flex-PCBs and exotic materials.

“This acquisition is representative of our strategy to drive growth and expand the scope of our technology so we can address a greater share of the market. We will continue to look for opportunities that make us a more important partner to our customers.” – MB

Around the World
Benchmark to Close 2 Sites, Lay Off 300 Workers
TEMPE, AZ Benchmark Electronics will shutter assembly sites in San Jose and Guaymas, Mexico, by the end of next March and lay off about 3% of its global workforce.

Benchmark didn’t specify how many positions would be cut, but based on the firm’s fulltime headcount as of Dec. 31, the total would be about 315. The company also employs about 1,500 contract workers.

The two sites make up 4% of Benchmark’s global footprint of about 4 million sq. ft.

The sites combined serve fewer than 20 customers and build products for a variety of end-markets. Customers are expected to be moved into other locations by the end of the first quarter 2020.

Around the World
Flex to Incur Up to $320M in Restructuring Charges, Might Lay Off Thousands
SAN JOSEFlex will take up to $265 million in charges over the next three quarters in part related to layoffs of an unspecified number of workers.

That’s in addition to the $56 million in restructuring charges it booked in its fiscal first quarter ended Jun. 28. With potential additional costs in the range of $145 million to $265 million over the next nine months, the total restructuring charges could top $320 million in its current fiscal year.

Flex is making the moves in part due to the expected loss of Huawei as a customer. Huawei, which made up roughly 5% of Flex’s quarterly revenue, was reportedly outraged when the EMS company held back shipments and raw materials to comply with US government edicts.

See us at SMTAI Booth # 223
Around the World
Flex Opens 4th India Assembly Site
CHENNAI, INDIAFlex opened a 159,000 sq. ft. manufacturing facility here, its fourth in India.

“We are thrilled to celebrate the inauguration of our latest manufacturing facility in India that offers one-stop solutions ranging from engineering, manu-facturing, and supply chain and logistics services to increase our customers’ com-petitiveness and decrease time to market,” said Richard Hopkins, senior vice president of operations at Flex. “This further reiterates our continued commitment toward the Government of India’s Make in India vision and entrenches India’s position as an important manufacturing base for Flex.”

Flex has 10 other sites in India, providing manufacturing, after-market services and global business services. – MB

Around the World
CA Briefs
AIM Solder opened a new full-line manufacturing facility in the Changxing district of Huzhou, Zhejiang Province, China.

AirBorn broke ground on a $3.7 million investment that will double its size in Pennsylvania and add up to 249 new jobs.

Apple will acquire the majority of Intel’s smartphone modem business for $1 billion.

Arrow Electronics will close its plant in Windsor, CT, in mid-September.

AT&T is working with a product division of Jabil to accelerate retail automation using autonomous robots with 5G wireless networking capabilities.

Laserssel named as representatives SW Systems Technology for the Southwest US and Mexico and Kurt Whitlock Associates in Florida.

Lite-On Technology reportedly plans to sell its storage business consisting of SSD products, with Toshiba Memory being identified as a potential buyer, according to industry sources.

Motion Sensors installed an Optical Control OC-Scan CCX.3 x-ray component counter.

Northrop Grumman is seeking firms with expertise in printed circuit assembly to support what it calls a “major project” dealing with a US Air Force program to replace the Minuteman III ICBM missile system.

See us at PCB West Booth # 201
Market Watch
EDITED BY CHELSEY DRYSDALE
DRAM Sales to Decline 38% in 2019
SCOTTSDALE, AZ Despite a 38% sales decline expected this year, the DRAM market is forecast to remain the largest of all IC product categories again in 2019, with sales of $62 billion, says IC Insights.

The DRAM market will account for 17% of total IC sales this year, according to the firm. By comparison, DRAM sales accounted for 23.6% of the total IC market in 2018.

The NAND flash market is forecast to slip from second to third position in the ranking, with total sales falling 32% to $40.6 billion in 2019. Taken together, the DRAM and NAND flash memory categories are forecast to account for 29% of the total $357.7 billion IC market this year, compared to 38% of the total IC market in 2018.

See us at SMTAI Booth # 305
ROI
The Skinny on Training in the Lean Organization
As the challenges of training evolve, so does the definition of lean.
An organization cannot become lean without tons of training.

Think about that oxymoron for a moment. It takes time to train, time that a lean organization cannot sacrifice. Training in this industry, which utilizes many varying yet intertwined processes, has traditionally taken the form of on-the-job training (OJT) versus a formal, classroom-style format. In any organization, especially a lean one, OJT is much easier to administrate and far less disruptive to employees and production than other types of training. In a service industry, even in support positions off the shop floor, it is much easier to take someone offline and plunk them down for formal training. In a lean manufacturing environment, however, excess resources in any given job function or department are rare. Hence, most training is integrated into the daily workflow as OJT.

But the type of training needed today is complicating this reliance on OJT. Owners or managers in manufacturing companies – regardless of industry – tell me the no. 1 issue they face is identifying, recruiting and hiring good employees. The subset to this challenge always mentioned by hiring managers includes themes along the lines of finding millennials who consistently show up for work; older people with skills or abilities; and anyone who is committed to a career versus a short-term job. Add language and legal status to the mix and hiring and retaining people – good people – becomes not just challenging, but almost impossible!

Board Buying
It’s Time to Bypass the PCB Broker
It’s adding unnecessary costs to your supply chain.
Want a more robust and cost-effective supply chain? Shrink it. Remove the expensive middleman. You don’t need to pay a PCB broker a 20 to 40% markup to, basically, relay information from you to overseas vendors.

The truth is the PCB broker business model – where companies buy printed circuit boards from an overseas manufacturer and then resell them to a customer – is outdated. And it’s adding unnecessary costs to your supply chain.

Years ago, brokers were small operations, with perhaps three to five people. And at one time, they did provide a valuable service to their customers, offering lower prices on boards made overseas, while handling all the details of procurement from foreign vendors in what was often a challenging PCB buying cycle.

For a couple of decades, brokers and customers had a symbiotic relationship that served the industry well.

PCB Guided Insights
Assembly Data and Documentation Process Overview, Part II
Prepping the data for placement and soldering.
In part one of this two-part series on assembly data and documentation, we discussed how data drive the assembly package and listed several items needed for it to be complete. Understanding this and the manufacturing process will help users make sound design decisions. This column provides a deeper dive into each step of this process.

Programming the placement machinery. Once the parts (including the PCB panels) are purchased, the automated assembly process can begin. Data required for this phase of the manufacturing process are taken from a few valuable sources. For the manufacturing engineer, the bill of materials (BoM) provides a limited view of the requirements. Along with the BoM output, the designer has hopefully provided an intelligent data format file for the design. With this information, the manufacturing engineer can get a good look at the design intent and begin planning the order of manufacturing operations.

The provision of x, y placement data output from the design database is invaluable to the process. Sometimes referred to as a “pick-and-place” file, the data can be fed into process programming to help select the proper tape reel and define the nominal location and rotation for each SMT part that will be automatically soldered to the board.

Designer’s Notebook
Managing Time Delays
How to calculate trace length from time delay value for high-speed signals.
To keep a good high-speed signal quality from driver to receiver on a PCB is not an easy task for designers. One of the most challenging issues is managing the propagation delay and relative time delay mismatches. To manage the time delays, we need to know how to calculate trace length from time delay value in order to implement the PCB trace routing accordingly. Let me take you through the process.

Calculating signal speed. According to physics, electromagnetic signals travel in a vacuum or through the air at the same speed as light, which is:

Vc = 3 x 108M/sec = 186,000 miles/sec = 11.8 in/ns
A signal travels on a PCB transmission line at a slower speed, affected by the dielectric constant (Er) of the PCB material. The transmission line structure also affects the signal speed.
The Route
The Digital Route: From EMI to RF
The latest reports from the local chapters.
We’re onto the second half of the year now, and we’ve seen a lot of activities within our local Designers Council (DC) Chapters, including a few international chapters. It’s great to see and hear about the continued activities from professional development to knowledge sharing and networking taking place at various industry events. Here is a snapshot of what has taken place so far from several of our active chapters.

If you are involved in discussions about industry content regarding PCB design, fabrication or assembly, whether it is in a small or large group, but you are not part of IPC, then I highly recommend you contact me so I can assist you in joining the IPC collective. It’s free and well worth it! And if you are an industry veteran with much experience, yet not active in IPC, or simply a college student starting your career, this is a great group to join and get plugged in. I hope to hear from those who are not part of IPC, especially within a DC chapter.

Material Matters
How to Avoid Getting Totally Skewed, Part Three
Mitigation techniques and costs of designing around glass-weave skew.
Au: This column is a comprehensive follow-on to the July column introduction on glass-weave skew and the discussion in August of various mitigation strategies. With some overlap, these may be read together or independently.

In July, I introduced glass-weave skew causes and when or why a hardware designer might care. In Part Two, I discussed various mitigation techniques and cost. Here, I’ll do a deeper dive into the impact of glass styles on precipitating or mitigating skew. Part Four will cover dual-ply and low-Dk glass.

While glass-weave skew (GWS) is a real problem, it’s hard to characterize because it is statistical in nature. What is the chance one line in a pair will see a different dielectric constant than the other? It depends on the pitch of the lines, the length of the lines, the laminate composition, and the relative chance alignment of the glass bundles under the two lines. Not to say it’s the best way to mitigate glass-weave skew, but glass-style selection provides the least expensive way to mitigate the “fiber-weave effect,” as it’s often called.

The standard. Before we go into the pros, cons and differences between different glass styles as they relate to glass-weave skew, we need to start with concrete definitions and specifications that you can hang your hat on – things that the industry as a whole has already agreed on.

See us at PCB West Booth # 618
Material Gains
Will Self-Driving Vehicles Sharpen Our Focus on Reliability?
The nature of ADAS could revive CAF fears.

In a previous column, I enthused about the prospects for 5G to transform lives for the better, supporting new services that take advantage of ultra-reliable low-latency communication (URLLC) and capacity for massive machine-type communications, or mMTC. One place the impact of 5G will be felt is on the road, where machines will assume the entire decision-making from humans.

Leveraging 5G’s guaranteed latency below 1ms for effective real-time performance, the prospects for mission-critical V2X vehicle-to-everything communication can become real. Vehicle-to-infrastructure interactions with smart signs should result in smoother, safer journeys, and vehicle-to-vehicle connections that share information about presence and position should avert huge numbers of “sorry, I didn’t see you” accidents. Of course, it will take time for smart infrastructure to evolve and for V2X-equipped cars to enter the market. But it’s quite clear, even now, that cars are destined no longer to be islands. Ultimately, it’s a matter of when, not if, our road journeys come to be handled by fully self-driving vehicles.

There are still many technical hurdles to overcome, as well as legal issues, not to mention cultural obstacles. On the other hand, we can gain tremendous benefits by separating the privilege of personal mobility from the burden of car ownership. Cost-effective services delivered on a pay-per-use basis can extend access to groups excluded by current models based on vehicle ownership, such as those on low incomes or allowing the elderly to lead independent and active lifestyles into later stages of life than ever before. As we age, I suspect that more of us will tune into the benefits of being able to summon a self-driving vehicle whenever we need, be it to get somewhere or just for a change of scenery.

NTI-100
5G Build-Out Will Speed PCB Fabricators’ Gains
After years of taking a backseat to mobile device fabs, multilayer manufacturers stand to reap the rewards. by Dr. Hayao Nakahara

There is an ongoing changing of the guard when it comes to drivers of the PCB industry. Mobile and PC-related end-products are slowly giving way to the emerging 5G infrastructure. This swing is just beginning to impact the NTI-100 list of the world’s largest fabricators, but it’s only one of the new trends seen as we collected and analyzed this year’s data. Another interesting development: A pair of fabricators from the US and Europe have come to dominate their respective “home” regions.

This year’s NTI-100 report is the 22nd in the “top fabricator” series since the author started in 1998. (The “100” refers not to the number of companies ranked but rather the entities with $100 million or more in PCB revenue in the last calendar year.) As more Chinese PCB fabricators achieve sales revenues of $100 million or more, many privately owned, it is becoming extremely difficult to get accurate data. Without the help of CPCA, this work would have been impossible. The author would like to express his gratitude to Angela Chen of CPCA, who collected valuable data. Although the data have some flaws, they are no fault of CPCA.

Some fabricators may have been missed, and others should not be on the list. There are more than 2,400 PCB fabricators in the world, half in China, and many Chinese fabricators are elusive and hard to get data from. Nevertheless, as usual, any errors are strictly the responsibility of the author. His confidence level in the data’s accuracy continues to decline every year, and if we were to put a number on it, it may now be 95%. He asks readers to be open-minded and tolerant of any errors.

See us at SMTAI Booth # 410
Prototron circuits
Prototron Circuits:
2 Sites, 1 Vision
The West Coast-based fabricator is turning boards up to 30-layers as fast as they get them. by Chelsey Drysdale

Sometimes two are better than one.

Take Prototron Circuits. The 30-plus-years-old board fabricator operates two factories in the Western US, and while they are hours apart by air, insofar as how the company sees them, they might as well be on the same campus.

In May, PCD&F visited the printed circuit board fabricator at its facility in Redmond, WA. The plant, which doubles as the company headquarters, is about 1,500 miles northwest of its other site in Tucson, AZ. But in the minds of the staff, the two plants act as complementary standalone facilities, serving thousands of customers each year.

“They do things we don’t do, and we do things they don’t do,” said Mark Thompson, engineering support, who gave the factory tour. He and Lee Salazar, Western Washington sales, answered questions before walking PCD&F staff through the 25,000 sq. ft. plant. (The Tucson facility is 20,000 square feet.)

Inemi Roadmap
Market Forces and Regulations Converge on Eco-Design

Cost savings, boosted by European Commission initiatives, drive product designers to implement eco-design. by Pamela J. Gordon

Ed.: This is the first of an occasional series by the authors of the 2019 iNEMI Roadmap. This information is excerpted from the roadmap, available from iNEMI.
A common misconception is that eco-design adds costs to products. In fact, nearly every eco-design principle reduces product costs. The growing demand for more environmentally sustainable products, coupled with increasing regulatory restrictions, is motivating electronics manufacturers to leverage eco-design principles and the circular economy model to simultaneously build business value, decrease product costs and mitigate harm to the environment and society. Progress in eco-design since the 2017 iNEMI Roadmap has been driven largely by upcoming requirements from regulatory bodies and competition-driven initiatives; the latter stems from stakeholders’ increasing awareness of the toxicity, CO2 emissions, social inequities, and costs attached to many materials in the extraction, manufacturing, transportation, use and post-use phases.

The European Commission (EC) remains the most active driver of regulatory eco-design requirements, especially in removing hazardous substances from products and in creating mandates for new standards related to the circular economy. For instance, the electronics industry is actively removing four phthalate substances in advance of RoHS restrictions that take effect starting in 2019. Also, in early 2018, the EC launched its next round of substance reviews for possible restriction in electronic products. 

Moreover, 10 European standards to enable future initiatives and regulations on the circular economy are in the final stages of development. These standards address definitions, requirements and methods for product durability; ability to remanufacture as well as to repair, reuse, and upgrade; recyclability and recoverability; and a proportion of reused components and recycled material. (According to the Ellen MacArthur Foundation, the circular economy is a way to design, make and use things within planetary boundaries, by designing out waste and pollution, keeping products and materials in use, and regenerating natural systems.)

See us at SMTAI Booth # 824
PCB Cleaning
Is Your Contact Cleaner Compatible with Today’s Complex Electronics?
Some cleaners are speedy and effective but can attack plastic components. by Emily Peck
With modern electronics getting smaller and more complex, finding a reliable cleaning method that is both effective and compatible with the different materials of electrical equipment can be difficult. The smallest contaminant can form a barrier between contacts and parts, or initiate dendritic growth, affecting the device’s efficiency and performance. This is why cleaning plays an important role in guaranteeing the quality of electronics equipment coming off the production line.

Contact cleaners are widely used in the industry due to ease of use and convenience. They clear particulate and oil residues from hard-to-reach places and refresh electrical connectivity on switches, relays, potentiometers and other devices. They safely rinse grit from hot motors and dust from inside electromechanical relays and keyboards. They are also effective in removing contaminants from hard-to-reach areas on connectors, cable harnesses, tuners, power supplies, encoders, distribution panels, junction boxes and switching devices.

The perfect contact cleaner should be nonflammable, noncorrosive and have strong dielectric properties. Ideally, it could even be sprayed on energized electrical circuits without concern. The cleaning agent must be safe for use on all component materials without risk of damaging delicate parts. These features may be the ultimate contact cleaning combination, but some electronics manufacturers may not be taking time to check the cleaners used are up to the job and compatible with electronic components.

See us at SMTAI Booth # 410
Test and Inspection
Defining Acceptable Voiding Levels Under QFNs
Will IPC accept the >50% voiding recommendation?
We have long had numerical guidelines for voiding levels below which we deem acceptable for BGA joints. Originally from IPC documentation, the limit called for less than 25% voiding of the joint area when the joint is looked at from the top-down in x-ray. More recently, and entirely because of evidential data, this has been increased to 30%.

Many other joint types also given designated qualifications in the IPC guidelines, such as through-hole joint fill levels, can be evaluated using x-ray. However, there has always been an anomaly in the level of voiding in bottom termination components (BTCs). To date, no evidence-backed, indicative values are published detailing acceptable voiding in these joints and, in particular, the large central pad under QFNs.

The primary reason for this is the lack of appropriate data upon which to base a criterion. Without evidence, the standards writers cannot propose values that will impact how our industry does business. For QFNs, however, this is now all set to change. For that we thank Dave Hillman, chairman of the IPC Voiding Task Group, and his merry band of volunteers. I had the good fortune to listen to Hillman’s presentation at the recent SMTA International Conference for Electronics Enabling Technologies (ICEET) titled “Reliability and Voids in QFN Solder Joints: What’s the Issue?” Hillman showed data from device manufacturers that indicate thermal performance of large central MLF pads as a function of solder void. (See IPC-7093, Figure 6-19.) This is a performance criterion, however, and while it may set an upper voiding limit to define a failure level, it does not necessarily indicate what value(s) could, or should, be used as a manufacturing process indicator. To correct for this, Hillman presented initial data on lifetime solder joint integrity as a function of void size in QFN central pads for tin-lead and lead-free solders. Further papers on this topic will be presented this month at the SMTA International Conference.

Test and Inspection
Further Field Studies
As we venture out among the aerospace industry, it helps to know the lingo.
Four years have elapsed since we last provided discerning readers with a helpful field guide to the major species inhabiting trade shows. Four years is a long time. Has anything changed? Have the major species evolved? Regressed? Have some gone extinct or suffered outright obsolescence? What are the replacements?

The quest for knowledge beckons us back to the field.

Curiosity about a changing world and an evolving industry propels us to don pith helmets and binoculars and return to the source. Post-graduate work commences now.

Today’s trade show showcases military and aerospace supply chains. Four years ago, we looked at electronics, broadly based, with commercial applications. Wares were hawked, and sales methods were scrutinized at well-known commercial and industrial events. Today we consider items that shoot, explode, report, eavesdrop, interfere (jam), transmit, receive, intercept, and encrypt or decrypt. To exact specifications. Objects sold here ascend, plummet, and follow ballistic trajectories on one-way missions, the warranty expiring on impact (no extension needed). They may settle into low earth or geosynchronous orbit. In many cases, they fulfill an application in which a protagonist initiates action at one end, and their antagonist resides at the receiving end of the transaction. The result is usually transformative for one party. That’s a diplomatic way of saying they have a limited lifespan. Some win, some lose.

See us at SMTAI Booth # 1224
Getting Lean
An In-House Solution to Odd-Form Part Inspection
When commercial AOIs were not up to the task, a little internal ingenuity saved the day.
While there is great debate in the quality community as to who first made the observation that visual inspection by humans is not 100% effective (both W. Edwards Deming and Dr. Joseph M. Juran have been given credit) and even some debate about the true effectiveness rate (is it 75%? 80%? 85%?), all agree it is inefficient and error-prone. Yet, automated optical inspection is often deemed not cost-effective for relatively simple processes in many factories.

One area that is often problematic for electronics manufacturing services providers is odd-form part through-hole insertion. Through-hole odd-form parts continue to be used when a part’s weight or need for a more robust solder joint makes that level of interconnection more reliable. Transformers, large capacitors, diodes, relays, connectors and pressure sensors are few examples of parts that are often still packaged as through-hole. Manual assembly, like manual inspection, is prone to variation and associated defects, particularly issues such as misaligned parts, missing parts or wrong parts. Odd-form parts are typically of a size or shape that makes automated insertion methods impractical.

SigmaTron’s facility in Chihuahua, Mexico, performs high-volume assembly of products, which includes printed circuit board assemblies (PCBAs) with paced, manual assembly requirements driven by odd-form parts. The engineering team wanted to automate the visual inspection process of that segment of production. Commercially available vision systems were cost-prohibitive, and in most cases could not be customized to inspect the full range of parts that needed inspection. So, the team decided to create its own inline inspection system, utilizing in-house process engineering, machine shop resources, technicians and test engineering development personnel. The engineering team developed a system using an off-the-shelf camera system and mechanical components combined with internally developed software and fixturing for each board type.

Defect of the Month
01005 Termination Lift
Inappropriately sized pads can result in excessive solder and, eventually, defects.
This month we show soldering of 01005 chip resistors from an early project with lead-free assembly. The microsection image in FIGURE 1 shows a few issues, but it’s the circles in both joints that caught my eye. Yes, they are voids before they are unmasked. During sectioning we stopped just before entering the void. Most would have continued a few more micros to remove the thin sliver of solder, which was the wall of the void, to show the void. But everyone has seen voids before!

Now to the important part. The pad size is too large for this small passive device and contributed to the addition of too much paste during printing. The length of the pad was reduced in further trials. During soldering, solder reflowed and wet over the top of the resistor termination. This resulted in lifting of the wraparound termination on both sides.

See us at SMTAI Booth #410
Off The Shelf
Off The Shelf
Machines Materials Tools Systems Software
HORIZONTAL WET PROCESSING
Horizontal Wet Processing
Polygon PLB horizontal production equipment line is for multilayer, rigid-flex and HDI panel processing. Wet-in-wet, inline, desmear and electroless copper production line has advanced fluid delivery system, reduces consumption rates for chemistry and water, and an operator-friendly design. Comes with Securiganth and Printoganth product series.
Atotech
S-PARAMETER LOSS ANALYSIS
S-Parameter Loss Analysis
Si9000e now comes with LA9000 S-parameter loss analysis options and new Monte Carlo analysis option. Updates bidirectional copy/paste interface between Speedstack and Si9000e. Has improved support for loss tangent (Ref TanD). Causal modeling now extended to copper losses.
Polar Instruments
WIRE-TO-BOARD CONNECTOR
Wire-to-Board Connector
DF51 series 2.0mm pitch connector has a lock that provides a clear tactile click and secures a reliable connection. Dual side-lock design prevents socket lift due to vibration or cable wrenching. Crimp connector comes in straight, right-angle, inline connection, and single- or dual-row. Single-row versions are offered in two to six positions, while the double row comes in four to 30 positions. Operating temp. -40° to +105°C.
Hirose
Technical Abstracts
In Case You Missed It
Advanced Materials

“Metal Oxide Semiconductor Nanomembrane-Based Soft Unnoticeable Multifunctional Electronics for Wearable Human-Machine Interfaces”

Authors: Kyoseung Sim, Zhoulyu Rao, et al; cyu13@central.uh.edu.

Abstract: Wearable human-machine interfaces (HMIs) are an important class of devices that enable human and machine interaction and teaming. Recent advances in electronics, materials, and mechanical designs have offered avenues toward wearable HMI devices. However, existing wearable HMI devices are uncomfortable to use and restrict the human body’s motion, show slow response times, or are challenging to realize with multiple functions. Here, the authors report sol-gel-on-polymer-processed indium zinc oxide semiconductor nanomembrane-based ultrathin stretchable electronics with advantages of multifunctionality, simple manufacturing, imperceptible wearing, and robust interfacing. Multifunctional wearable HMI devices range from resistive random-access memory for data storage to field-effect transistors for interfacing and switching circuits, to various sensors for health and body motion sensing, and to microheaters for temperature delivery. HMI devices can be not only seamlessly worn by humans but also implemented as prosthetic skin for robotics, which offer intelligent feedback, resulting in a closed-loop HMI system. (Science Advances, Aug. 2, 2019; https://advances.sciencemag.org/content/5/8/eaav9653).

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