Printed Circuit Design & Fab Circuits Assembly August 2020 Cover
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August 2020
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August 2020 • VOL. 37 • NO. 8
Printed Circuit Design and Fab Circuits Assembly logo
First Person
The virtues of virtual.
Mike Buetow
money matters
To remain flexible, we need to stay fit.
Peter Bigelow
With travel frozen, rethink and repurpose those marketing dollars.
Susan Mucha
Tech Talk
Studying the library.
John Burkhert
High reliability starts at the lowest level.
Alun Morgan
Navigating the flex roadmap.
Mark Finstad
Embrace the remote.
Clive Ashmore
Low-temperature soldering heats up.
Timothy O’Neill
Lifted parts.
Bob Willis
August 2020 • VOL. 37 • NO. 8
Printed Circuit Design and Fab Circuits Assembly logo
Application notes describe how to save layers in a PCB by routing two traces between pins on a 1mm pitch BGA. Are they correct?
by Lee Ritchey
Up Media August 2020 cover
RF Design
Transformers and inductors used in power and telecommunication applications are often the more expensive devices in a system design. When realizing a power converter or RF module, cost and size reductions can be realized by combining the magnetics and PCB functions.
by Jim Quilici
Component Inspection
Does a small node suggest anomalies – and potential failure? A combined x-ray and ultrasound process investigates.
by Tom Adams
Covid-19 drove a new medical device OEM to request a product ramp at high speed when other supply chain options were unexpectedly shut down. How a cross-functional team model and real-time systems completed an 800-piece validation order in fewer than 10 days and began full production in less than two weeks.
by John Sammut
Five recommendations for ensuring long-term access to key component packages.
by Martin Hart
IN the Digital Edition
The grand opening of the Printed Circuit Engineers Association.


Benchmark Lark’s New Fab/Assembly/Test Plant
with Kevin Walker
Electronic Debugging Tools
with InspectAR
The Latest PCB CAD Market Trends
with Wally Rhines
Supply Chain Changes in the Covid Era
with Christopher Tang, Ph.D.
POSTMASTER: Send address changes to
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Caveat Lector
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Living in the Virtual World


ome 13 years ago, UP Media Group launched the first virtual trade show for the electronics industry. In some ways – most, probably – we were ahead of the times. People liked it because it was simple to attend, but the platform wasn’t ready for prime time.

That’s not to say it was technically subpar. You could pop in and out of booths and talk to the personnel waiting for you, and I still feel for those folks who, driven by caffeine and excitement (or just an affinity for self-abuse), kept vigil around the clock as attendees in different time zones came on line and into the show. And we held webinars and chats with high-profile experts like Dr. Eric Bogatin. But in the end, attendees seemed to prefer meeting with peers face to face.

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Around the World
PCDF People
Jeffrey Korpus headshot

Bowman promoted Jeffrey Korpus to manager of the company’s Standards business Unit. He formerly was project manager and support engineer with responsibility for new standards design and team management, and managed Bowman’s quality system.

Charles Pfeil has released the second version of his e-book on High-Speed Constraint Values and PCB Layout Methods, available at

MacDermid Alpha appointed Fabio Taiana vice president Assembly Solutions – Europe.

Sierra Circuits named Roy Alcus director of manufacturing.

Around the World
UPMG Announces Technical Sessions for PCB West Virtual 2020
ATLANTA – UP Media Group announced more than 40 technical sessions – totaling more than 125 hours – have been selected for PCB West Virtual 2020 this fall. The conference, which is moving to an online platform because of the novel coronavirus, takes place Sept. 7-10.

This year’s conference features a pair of extended talks from Lee Ritchey on power delivery system design and stackup design, two talks from Dr. Eric Bogatin, and three full days of classes from Rick Hartley. The conference covers everything from RF/microwave and mixed-signal design, circuit grounding, understanding material choices, flex circuits, signal and power integrity, to fabrication and assembly processes. Talks are aimed at the spectrum of backgrounds, from novice to advanced.

Around the World
IPC, IAEG Encourage Use of IPC-1754 in Aerospace, Defense Industry
BANNOCKBURN, IL – IPC and International Aerospace Environmental Group issued a joint statement encouraging use of IPC-1754, Materials and Substances Declaration for Aerospace and Defense and Other Industries, in the aerospace and defense industry and its global supply chain.

Obtaining data from the supply chain to support chemical content reporting for article (hardware) products remains challenging and resource-intensive for industries such as aerospace and defense, the trade groups said. Increasing use of materials and substances declaration standards promotes efficiency in obtaining such data, however.

The standard, which is voluntary, supports data acquisition for various substance reporting requirements for article products, including data required by the EU’s Waste Framework Directive for reporting to the SCIP database. Under the WFD, European article suppliers subject to SVHC reporting under REACH Article 33 will also be required to report SVHC data to the SCIP database. However, SCIP reporting will also require additional data elements such as material and product identifiers.

IPC-1754 supports all data elements needed for reporting to SCIP. In support of SCIP reporting, IPC is developing guidance for using IPC declaration standards when acquiring the necessary data. IAEG is also developing supporting general information for the use of IPC-1754 and related IAEG-developed tools in the AD industry supply chain, available on the IAEG website. (CD)

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Around the World
CA People

Escatec named Patrick Macdonald chief executive.

Intelligent Manufacturing Solutions (IMS) named Jim Barry director of business development. His experience includes 14 years as president of Eltek USA and seven years in executive positions at Strataflex.

Steve Korn headshot

Kimball Electronics promoted Steve Korn to president of Global Electronics Manufacturing Services Operations, and Lee Kemper to vice president of Diversified Contract Manufacturing Services.

Trever Winters headshot

Libra Industries appointed Trever Winters VP of operations at its Dayton, OH, facility. He has experience as master scheduler, supply chain analyst, and most recently site manager.

Moog named John Hengst SMT manufacturing engineer.

Mostafa Aghazadeh of Intel has been elected chairman of the iNEMI board of directors.

Around the World
Benchmark Adds Fab Shop in Phoenix
PHOENIX – Benchmark Electronics has joined the ranks of vertically integrated manufacturers with its new 122,000 sq. ft. state-of-the-art factory in Phoenix. The end-to-end process encompasses a dedicated design center, board fabrication, assembly and test, highlighted by a state-of-the-art factory 4.0 lights-out SMT line.

The plant, which houses a Benchmark Lark Technology team, as well as other Benchmark operations, celebrated its grand opening in June.

It is the fourth greenfield fabrication plant built in the US in the past 20 years, the others being Whelen Engineering’s captive shop, which opened in 2015; GreenSource Fabrication, which launched in 2018; and TTM’s new plant in Chippewa Falls, built in a converted 20-year-old, 40,000-sq. ft. warehouse and officially opened last winter.

Benchmark is the fifth-largest EMS company in the US and 18th in the world, according to the Circuits Assembly Top 50.

Around the World
IPC Releases New Press-Fit Connector Standard
BANNOCKBURN, IL – IPC announced the release of a new standard for the qualification and acceptance of press-fit technology. IPC-9797, Press-fit Standard for Automotive Requirements and Other High-Reliability Applications also includes high-reliability needs for automotive and other industries such as aerospace.

Press-fit technology is relatively new to the automotive industry and high-reliability needs but not to electronics, IPC said. Used primarily in the telecommunications industry, the dependability and efficiency of press-fit makes it stable for use in high-reliability electronics.

The technology has been found to be critical to the manufacturing of electronic and electro-mechanical components. (CD)

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Around the World
CA Briefs

A bipartisan pair of US senators have introduced a bill to restore semiconductor manufacturing to American soil by increasing federal incentives to stimulate advanced chip manufacturing, enable cutting-edge research and development, secure the supply chain and bring greater transparency to the microelectronics ecosystem.

ASE Technology, Powertech, SPIL and Amkor plan to take advantage of incentive schemes recently announced by the Indian government to set up semiconductor packaging and test services in the country.

Acer is seeing shortages of components, including passive components, ICs and panels by around 30% due to surging orders from the end-market, according to co-COO Tiffany Huang.

Adco Circuits has developed a free instant costing tool for circuit board assemblies that takes a bill of material and outputs a price with complete unit costs.

AIM Solder opened a stocking facility in Manaus, Brazil.

IPC Class 3 Design Guide text
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Sierra Circuits logo
IPC Class 3 Design Guide text


What is IPC?

Class 1, Class 2, and Class 3 PCBs

IPC Guidelines for Manufacturing Defects

IPC Standards for Annular Ring

Design Rules for Annular Rings

IPC Standards for Assembly Process

IPC Standards for Solder Joints

Common Differences Between IPC Classes

PCB Cross-Section Verification

IPC Documents to Set the Level of Acceptance Criteria


What is IPC?

Class 1, Class 2, and Class 3 PCBs

IPC Guidelines for Manufacturing Defects

IPC Standards for Annular Ring

Design Rules for Annular Rings

IPC Standards for Assembly Process

IPC Standards for Solder Joints

Common Differences Between IPC Classes

PCB Cross-Section Verification

IPC Documents to Set the Level of Acceptance Criteria


What is IPC?

Class 1, Class 2, and Class 3 PCBs

IPC Guidelines for Manufacturing Defects

IPC Standards for Annular Ring

Design Rules for Annular Rings

IPC Standards for Assembly Process

IPC Standards for Solder Joints

Common Differences Between IPC Classes

PCB Cross-Section Verification

IPC Documents to Set the Level of Acceptance Criteria

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Market Watch
Calm Before the Storm?

Trends in the U.S. electronics equipment market (shipments only).

Computers and electronics products
Storage devices
Other peripheral equipment
Nondefense communications equipment
Defense communications equipment
A/V equipment
Nondefense search and navigation equipment
Defense search and navigation equipment
Medical, measurement and control
rRevised. *Preliminary. 1Includes semiconductors. Seasonally adjusted. Source: U.S. Department of Commerce Census Bureau, July 2, 2020
Covid-19 has Forced Us to Change. Will It Stick?
We must retain our new agility even after the pandemic ends.
Nothing makes you flexible like a crisis. Yet, as rough as it can be for a person to quickly shift gears, it is significantly more daunting for a corporation to do so.

The entirety of my working career, the mantra of any good business consultant or culture guru has been be flexible and embrace change. Whether an organization is implementing a TQM (total quality management) plan or struggling with financial survival because “plan A” no longer works, embracing flexibility and rapid change is never easy – and often unsuccessful. The larger the organization, the harder it can be. Embracing change and becoming flexible often only occurs when no other option remains, or in short, extinction awaits.

focus on business
The Covid-19 Sales Challenge
With travel frozen, rethink and repurpose those marketing dollars.
By making face-to-face sales calls impossible, Covid-19 is challenging electronics manufacturing services (EMS) salespeople to work in new ways. Sadly, that challenge isn’t likely to go away soon. On the bright side, it opens the door to a more productive, less costly sales and OEM relationship, provided salespeople modify their approach.

In the normal flow of EMS selling, there is typically a lead follow-up phase that results in a face-to-face sales call. There may be an additional meeting to present a quotation, depending on the distance between the salesperson and decision-maker. There is also usually a plant tour. When all these activities are local, costs drop to the amount of time the individuals spend on the activity. However, the cost of a sales call that involves business travel may be $1,000 to $2,000, depending on mode of travel and how many sales calls are clustered into that trip.

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Generating PCB Footprints for Your First Layout
And why your library naming convention should be memorable.
As a designer who has put himself into the public eye, a lot of questions come my way. Several beginners have approached me with basic questions I can usually answer by sharing something I’ve already written. Sometimes I’ll end up writing a few paragraphs that eventually expand into a column to share with everyone. One gentleman, whom I will call Aakash, has leaned on me so many times I think he might be compiling a book. The messages pile up, as do the answers. Let’s get to one of those types of answers.
More than one person has asked about starting their first job going from the ground up. “How do I make all the parts I need for my first board?” The short answer is to build them one at a time. This is the internet age. This is the 21st Century. There must be a better way! It’s not that we’re impatient; we just don’t have that kind of time. Software vendors know that, and the internet does too. The software installation comes with a bevy of common parts, but most boards go well beyond the generic SMD capacitors and resistors found in the default library.
PCB Layout
Figure 1. The PCB layout can only be as good as the underlying footprints all the way down to the padstack where it all begins.
Material Gains
Reliability Needs to be Designed-In from the Lowest Level
Cutting-edge technology demands more care to ensure reliability and resilience.
Human nature is to invent, to create technological solutions to the challenges and problems we see. We are increasingly dependent on high-technology solutions as we address more complex issues. Some of these issues are of our own making. Others arise from our increasing expectations: what we want to do, where we want to go, how safe we want to feel.

All this keeps the electronics industry extremely busy. And the equipment we create – remote smart sensors, street-level broadband infrastructure, full-color digital signage, supercomputers on wheels (or wings) – is more and more likely to be required to operate faultlessly in extreme environmental conditions. Gone is the era when advanced electronics assemblies were mostly destined to spend their lives in air-conditioned telecom offices or otherwise benign environments. Now, they are out in the cold. And the heat. And the humidity. And this presents a major reliability challenge that needs to be addressed at every level from the installation and the enclosure down to the substrate.

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The Flexperts
How to Really Read a Technical Roadmap
It might be factually correct, while also being completely impossible.
Question: I am looking to add a flex circuit supplier to our vendor base and requested its technical roadmap. After review, it appears almost exactly as the two vendors we currently have. Is this a coincidence, or do most (or all) flex suppliers have the same technical capabilities?

A technical roadmap is basically a document that outlines what a company can and cannot do from a technical standpoint (e.g., minimum trace/space, layer count, pad and via size, overall circuit size, etc.). I have never been a fan of technical roadmaps. Virtually every flex (and rigid) PCB supplier is compelled by their customer base to provide their capabilities, and therefore also their limitations. The problem with roadmaps is twofold. First, every supplier advertises the absolute best it has ever done in every single category. This is true even if it only did it one time, on one circuit, and in a beaker. This is not a fair representation of what the fabricator can or cannot do on production quantities. The second problem is the real answer for what a supplier can or cannot do is “it depends.” Let’s look at a few examples.

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Why Not Route Two Traces Between Pins on a 1mm Pitch BGA?
A look at the geometry associated with plated through-holes in a PCB. by LEE RITCHEY

Application notes describe how to save layers in a PCB by routing two traces between pins on a 1mm pitch BGA. A leading FPGA vendor recommends this practice to use its very-high-pin-count FPGAs in a low-layer-count PCB. When this approach is used for a high-layer-count PCB, the result is often, if not always, very poor yields, and the board is unreliable when used in a system under actual conditions, as opposed to in a laboratory or a prototype built in a small volume by a specialty shop. The following discussion will illustrate why this approach results in unsatisfactory yields when volume manufacture is attempted.

To understand the space used to route traces in signal layers of a multilayer PCB (this also applies to four-layer PCBs), it is useful to look at how plated through-holes (vias) are created and the various requirements that must be met by the finished PCB. FIGURE 1 is an illustrated cutaway of a plated through-hole showing signal and plane layers.

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The PCEA’s Grand Opening

This month, I spoke with Rick Hartley about his presentation for the PCEA’s grand opening webinar on Jul. 14. Next, PCEA Chairman Steph Chavez shares a timely message on how our time working from home is a serious matter, and how letting our guard down could be a mistake.

Again, PCEA chapters are in transition, and due to social distancing requirements, no face-to-face meetings have taken place to date, but a lot of virtual activity is happening. I also share our most updated list of professional development opportunities and events, which we hope you find useful.

PCEA Updates

In this interview with Rick Hartley, we discuss the PCEA’s grand opening webinar on Jul. 14, where he presented a free class on PDN tips for successful power distribution. For access to the on-demand event, click here.

RF Design
Leveraging common fabrication processes to encapsulate transformers. by JIM QUILICI

Like embedded resistors and capacitors, embedded magnetics provide a means for reducing system size and cost. Transformers and inductors used in power and telecommunication applications are often the more expensive devices in a system design. When realizing a power converter or RF module, cost and size reductions can be realized by combining the magnetics and PCB functions. This article provides an overview of embedded magnetics design and construction.

Inductors and transformers are basic building blocks of power and communication systems. A simple transformer or inductor can be implemented between two PCB layers. FIGURE 1 shows a cross-section of an embedded magnetic transformer. A cavity is milled into an FR-4 substrate. Ferrite cores are inserted and encapsulated in place with low-shrink epoxy. For those unfamiliar with ferrite material, it is a ceramic made by mixing iron oxide and metallic elements like manganese, nickel and zinc. The mixture is molded and fired to create a magnetic core. The materials are classified as ferromagnetic, meaning when a conductor is wrapped around the material and a current is applied, a magnetic flux will develop within the core and remain there as long as the current is applied. Permeability is a measure of the materials’ ability to build a magnetic flux. High permeability materials (5000 to 20,000) use a mixture of manganese and zinc (MnZn) and are generally used to produce RF inductors and transformers. Power applications also use MnZn, yet at a mixture that produces a much lower permeability, in the range of 1000 to 3000. RF and power applications also use inductors and transformers to filter noise. Nickel-zinc (NiZn) ferrites have lower permeability (800 to 2000), yet operate over a wider frequency band and are commonly used to filter noise. A system implementation may use a combination of ferrite cores. For instance, a power converter may use MnZn ferrites to temporarily store energy in a transformer or inductor, while also using inductors wound on NiZn cores to filter noise.

Component Inspection
Hidden Trouble in a BGA PACKAGE
Does a small node suggest anomalies – and potential failure? by TOM ADAMS
A small raised area was initially noted on the top surface of the plastic ball grid array (BGA) package discussed here. To learn whether there were other structural anomalies deeper within the package, it was imaged by both x-ray and ultrasound. The x-ray imaging was performed first, using a Nordson-Dage Quadra 7. When traveling through a sample, the x-ray beam is locally attenuated by the density and thickness of the material through which it passes. Very dense materials such as metals may limit the thickness of the sample that can be imaged, while materials such as plastic are far less attenuating. The completed x-ray image reveals in very high-resolution local changes of attenuation over the area being imaged.

FIGURE 1 shows one corner of the BGA’s die and the attached wires. All the wires are intact here and on the rest of the BGA. All features are encased in the nearly transparent (to x-ray) mold compound. The black circular features are the solder balls under the BGA. The indistinct gray fea-ture just above the edge of the die is caused by the variable thickness of underfill material extruded from beneath the die. Within the area of this image there could be delaminations or voids – i.e., air-filled gaps – on top of the die or in the die attach material below the die, but air attenuates an x-ray beam so slightly, and the gaps are typically so thin, that these gaps would not be imaged.

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A cross-functional team approach for completing prototypes and ramping to production. by JOHN SAMMUT
Faster, better, cheaper has always been a mantra in electronics manufacturing services (EMS) because leveraging the benefits of companies selling manufacturing expertise and infrastructure has been the primary motivation behind the growth of outsourcing. Improvements in computing technology, networking infrastructure and systems interconnection now give EMS teams unprecedented real-time visibility into the product realization process. But like the guy who buys a Porsche and drives mainly on city streets, these systems are rarely tested to their full potential. Firstronic’s new product introduction (NPI) team recently needed to break that paradigm when the Covid-19 pandemic drove a new customer to request a product ramp at high speed when other supply chain options were unexpectedly shut down.

A medical device manufacturer with an infrared thermometer had production shut down in its Tijuana-based EMS supplier as a result of Baja California-mandated Covid-19 restrictions. They needed to dual source as quickly as possible since this was a critically needed product.

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FPGA ISSUES and Concerns: A Real Danger and a Call to Action
The reality of a brittle supply chain could mean harsh consequences for failure to deliver. by MARTIN HART
A field programmable gate array (FPGA) is an integrated circuit configurable by customers in the field, making such devices desirable for space and defense applications. A fortified version, known as a Radiation Hardened (RadHard) FPGA, can withstand attacks from electromagnetic and particle radiation in outer space.

Columns, rather than solder balls, are a critical subcomponent in the final assembly of FPGA packages.

A sudden shortage of mission-critical FPGA devices could result in warfighters not flying and rockets not launching. This is not an exaggeration. But how could this be? Quite simply, makers of ruggedized FPGA devices depend on a single subcontractor to provide services to attach copper-wrapped solder columns.

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SCREEN printing
Print Productivity, Reliability and Remote Access: The Pillars of the Covid Era
Multitasking platforms are becoming the standard.
While productivity – manufacturing more product, more efficiently in less time – has been center stage in electronics assembly for decades, today’s razor-thin margins, coupled with the requirement for limited human intervention, have put an exclamation point on managing output proficiency. (This is especially true as the world restricts building access and maintains safe personal distances.) An optimized stencil printing process, as I’ve said many times, comes down to depositing the right volume in the right place at the right time. These are the three pillars of the print operation. Ultimately, for maximum productivity, a manufacturing operation needs a stencil printer that is always available and, when it is available, efficient and reliable.

It wasn’t long ago the bottleneck on the production line was usually the placement machine, so the stencil printer was generally available and had plenty of time to run the print routine. With recent modular approaches to manufacturing line setups, however, this is no longer the case. Placement platforms have exponentially improved speed. The printer now must maintain a much faster pace; this starts with mechanics and cycle time. In mass production settings, getting a printer down to a core cycle time of five seconds has become a necessity.

tech tips
Is SMT Ready for Low-Temperature Solders?
With no standard in sight, emerging alloys require unique fluxes and processes.

Low-temperature soldering is a subject of considerable interest and development. Several forces are driving implementation of solders with lower peak reflow temperatures than SAC 305 and its variants. The most technically significant is reduced warping of component and substrates. Chip suppliers are particularly interested in lower reflow temperatures, as thinner components are needed to meet dimensional limitations of thinner, smaller and faster devices. When a component deforms during reflow, the solder interconnect may be compromised, resulting in non-wet opens (NWO). NWO defects are difficult to detect and may not manifest until after a product is in the field. Other advantages of low-temperature soldering include the incorporation of lower-cost plastics, component and laminate materials, and reduced energy consumption and related environmental benefits.

As a practical matter, SnBi alloys are the only elements available to reduce peak reflow temperatures. Unfortunately, high-bismuth alloys have a number of disadvantages compared with the tin/silver/copper alloys currently in use. Bismuth alloys exhibit poorer mechanical and thermal fatigue performance than SAC-based materials. Minor element additions and micro-alloy elements can improve the performance of SnBi alloys, but, in general, they will retain the properties of their main constituents and lack the reliability and performance of their SAC-based relatives. Even with these limitations, SnBi alloys can be adopted for use in SMT and through-hole, but the main benefits are derived in surface-mount assemblies.

defect of the month
Root Causes of Component Lifting
Soldering in nitrogen or vapor phase environments can increase the likelihood.

Subtle component lifting can be an issue to find during inspection. Most modern AOI systems should be able to detect drawbridging on small passive and active parts. Old systems may struggle with defects like the two shown in Figure 1.

There are many papers on lifting of parts during reflow and many suggestions on the root causes. In our experience, the most common reasons are excess solder paste, an excessively thick stencil, or poor pad design. These issues are exaggerated by fast wetting, as seen in nitrogen and vapor phase soldering. To be clear, nitrogen or vapor phase do not cause lifting; they just increase the possibility of component lift.

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Off The Shelf
Off The Shelf
Machines Materials Tools Systems Software
D-2970 Dynamic series compact wire-to-board PCB connectors
Wire-to-Board Connectors
D-2970 Dynamic series compact wire-to-board PCB connectors have field-installable push-in clamp terminations. 5mm-pitch PCB connector operates at up to 20A and 400V at a typical ambient application temp. of 55°C without further derating. Features include audible and tactile locking latch, contacts that support shock- and vibration-exposed applications, and IP20 finger-safe housing. Push-in clamp and single-hand-operating center-locking lever reportedly cut mating time up to 90%.
TE Connectivity
InCAM Pro 2.1
Flex Tooling CAM
InCAM Pro 2.1 offers intelligent flex tooling hole placement in which all flex tooling holes on the board are visible at a glance. Adds and manipulates flex tooling holes on a new graphic mask layer that maps all flex tooling holes on the printed circuit board. The mask provides visibility to other layers when working with flex tooling holes. Automatically synchronizes tooling holes with relevant layers, saving hours of work and ensuring accuracy.
Frontline PCB
CR-8000 2020
3-D Multi-Board CAD
CR-8000 2020 has improved design efficiency, comprehensive system-level design and verification, and support for the latest advancements in packaging technology. Includes enhancements in schematic design, FPGA optimization, skew group routing and support of back-drilled vias; electro-mechanical co-design of flex-rigid PCBs and multi-domain analysis through direct integration of products from Keysight and Ansys; functionality for tile bump and 3-D wire design planning.
Off The Shelf
Off The Shelf
Machines Materials Tools Systems Software
1-Head Soldering Robot
TMT-R8000S has one head to simplify and automate hand soldering processes with precision ballscrews, servo motors and IP software. Includes vision/mapping, fiducial marks and dynamic laser height control. Separate drive motor for adjustable solder wire feeder.
YK610XE-10 Scara robot
Heavy Duty Scara Robots
YK610XE-10 Scara robot has 610mm arm length. YK710XE-10 Scara robot has 710mm arm length. Both deliver 10kg max. payload and standard cycle time of 0.39 sec. (YK610XE-10) and 0.42 sec. (YK710XE-10). Cover broader range of applications, encompassing assembly, conveyance, and sorting of small and large components.
Yamaha Motor Corp.
V810i 3-D x-ray inspection system
Large Board AXI
V810i 3-D x-ray inspection system inspects PCBs weighing up to 25kg. PCBs up to 1.3m x 1.3m can be inspected. Features algebraic reconstruction technique with model of sharp geometric 3-D CT. Produces quality images with digital tomosynthesis and x-ray autofocus technology. Inspects all forms of defects in SMT and PTH components. Monitors radiation exposures on component.
ViTrox Technologies
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Technical Abstracts
In Case You Missed It

“Vertical Interconnections by Electroless Au Deposition on Electroless Ni Immersion Au Surface Finish”

Authors: I. A. Weng, H. T. Hung, W. C. Huang, C. R. Kao and Y. H. Chen

Abstract: Electroless Au is used to vertically connect copper pillars with electroless Ni immersion Au surface finish on two stacked chips by a microfluidic electroless interconnection process. A low bonding temperature of 50°C and a pressure-less bonding process can be achieved. The vertical interconnections are formed by a forced flow of electroless Au plating solution through a microchannel, so the reduced Au atoms self-assemble between the gaps of facing copper pillars to complete the interconnections. The deposited Au grains span the entire gap across the two copper pillars, suggesting the rate-limiting step is more likely to be the nucleation than the growth of the Au grains. Four-point probe measurements show the average resistance of the electroless-Au-bonded interconnections is low. Mechanical shear testing reveals the bonding of the interconnections is strong. Further, it is demonstrated that this process can accommodate a high degree of pillar misalignment. (Journal of Electronic Materials, Jun. 5, 2020;

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