Quality printed circuit boards require more than quality manufacturers.

It never ceases to amaze me that OEMs and design bureaus deliver watered down and unintelligent data to their EMS vendors or manufacturing groups, yet keep their high expectations of high-quality products and consistent reliability.

One of our customers is a contract electronics manufacturer. He sent this actual example:

Table 1 is an excerpt from an actual customer’s BoM with incomplete data. These incomplete data cause significant time expenditures and delays. For example, on capacitor C101, what voltage rating and tolerance are needed?  For the screw and nut, what material (steel, brass, nylon, etc.), and style (slotted, Philips, hex, etc.)?

A number of factors drive the necessity for high-quality data. Shorter product lifecycles coupled with higher reliability expectations and lower cost mean the data should be correct and complete when delivered for manufacturing. The result: a growing need for effective, efficient utilization of intelligent data, from design through manufacturing. It is critical not only that complete and intelligent data be provided to ensure products have the highest quality and reliability, but to meet cost targets and critical release dates.   

Consider the importance of the manufacturing utilization of data. Manufacturing groups are highly dependent on product data received to provide outputs and information necessary for a manufacturing process to yield products of high quality and reliability. Manufacturers use these data for a large variety of things: BoM/MRP reports, defect statistics, and other manufacturability reports, DFx analyses (assembly, fabrication, and test), test programs, and other reports and programs. Without the intelligence embedded in good data formats, creation of these outputs is cumbersome, slow, or worse, exposed to error and data integrity issues.  

These two examples underscore the importance of high-quality data. Each requires higher quality intelligent data to permit manufacturers to take advantage of advanced solutions for the benefit of their customers (i.e., you):

1. Machine programming process with validation. With data consisting of top/bottom copper layer, silkscreen with polarity, component reference designators, and a BoM with accurate component information, manufacturers can validate SMT machine programs offline for rotation and offset issues at an engineer’s desk ($40-$75/hr. burdened rate), instead of relying on a live pilot run, which ties up production line time ($2,000-$7,000+/hr. burdened rate).   

2. Quality data system infrastructure. With data consisting of all board layers (internal and external) and the netlist, manufacturers have the baseline information necessary to streamline test and inspection loops on the shop floor. These data provide the means to quickly analyze and repair errors found through automatically collected test results of printed circuit assemblies using paperless visual aid tools and documentation.

Second, it is critical to understand the importance of the quality of data provided to the front-end process efficiency of your manufacturing group or third-party vendor. The type of data received can result in this process being measured in hours or days. Unintelligent data – single-layer Gerber files, DXF/HPGL files, PDF files (BOM or drawings), paper drawings – can add hours, if not days, to the processing time, just to get started on manufacturing, and significantly increase the cost. Using the same examples, this time with a focus on manufacturing process efficiency, it is easy to see the value of intelligent data.

1. Machine programming process with validation. The use of intelligent data (e.g., ODB++) to create and validate a complete machine program offline can be completed in less than 45 min., compared to 3 to 12 hr. with copper pad Gerber data only and standard BoM files, which lack CPL or IPC-D-356 netlist information.

2. Quality data system infrastructure. Without the use of intelligent data, such as netlist information, integrated into a quality data collection and analysis system, the ability to analyze and repair assemblies quickly and efficiently is a challenge. Using intelligent data can yield review processes that can take minutes, instead of hours spent searching for information on paper drawings and the tedious reviews that follow.  

The data a designer provides directly affect downstream process efficiency and the ability to utilize the data effectively for manufacturing processes. The next time you prepare to send a data package to a manufacturer, consider the ramifications of providing insufficient or unintelligent data on the resulting product’s quality, reliability and delivery time.

Michael Dryer is account manager, manufacturing team, Mentor Graphics Valor division (valor.com); This email address is being protected from spambots. You need JavaScript enabled to view it..

Five-and-a-half million: That’s how many light bulbs are purchased each day in the US. And yet, the market for incandescent bulbs is about to burn out. In fact, in Australia legislators have banned light bulbs, and the EU will switch off incandescent and halogen bulbs between 2009 and 2012. The mighty 100W bulb went out last year, and the 60W and 75W versions are next. In the US, the laws against incandescent kick in by 2012. (Halogen isn’t targeted.)

This throws open the door to a huge new market for fabricators and contract assemblers, but there are key differences from traditional SMT boards. In solid-state lighting, for instance, the LED and driver boards are separate, and the typical substrate for the former is metal core, not FR-4.

Thermal management, as our cover story last month detailed, is emphasized. While LEDs don’t throw as much heat as incandescent bulbs, there are still certain thermal issues to contend with. Most solid-state players try to design units that operate under a certain temperature to maximize output. “For an LED board, we look for a certain temperature at the joint,” says Scott Mauldin, director of operations of LEDnovation, a maker of LED lamps and luminaires. “This permits LEDs to get more lumens per watt” (of input).

LED parts for placement typically come on reels and can be put down by almost any decent placement machine. But there are advantages to be had: Smart feeders have a leg up, says Mauldin. Solid-state light manufacturers are interested in bin codes (which define the light characteristics of the LED). Bin codes might be mixed on a board to get the right amount of emitted light, which means assemblers must keep the bins separate.

In soldering, the thermal profile is very different than SMT parts. LEDs are sensitive to high heat. And rework is treacherous, as it is fairly difficult to heat up a single solder joint on a metal core board. (Some use hot plates for rework.)

A company like LEDnovation outsources assembly, emphasizing those with production experience with metal core boards, which eliminates about 80% of EMS companies today. That will need to change.

Mauldin is among the speakers at SMTA International’s EMS Forum (smta.org/smtai) this year. It’s definitely worth looking into.

Trading up. Apex/Expo and Nepcon China certainly showed vast improvement this year. Numbers were up at both shows, a reflection of the improving economy and (somewhat) open checkbooks. Especially noticeable at Apex/Expo was how engineers filled the floor through the third day: I would need a good miner to dig up a memory of the last time that happened. China’s rebound is not so much of a surprise, though it will be interesting to see how much longer that show lasts in the city when the Chinese government is doing all it can to push manufacturing out of Shanghai. And while the bloom is off the rose in Las Vegas, Apex at least demonstrated that North America can for now handle an annual event. (See our full report here.)

Dying dinosaur. The above notwithstanding, if you took $100,000 in cash and several thousands more in time and travel expenses and spent it trying to convince a handful of potential customers to buy your product, sometimes without even bothering to turn that product on, you would be hard pressed to convince an outsider this is a good way to run a business.

Yet, that is exactly what an SMT equipment trade show has come to represent.

That $100,000 – which is hardly a conservative estimate, as freight and hall drayage costs often reach $25,000 for a single placement machine, and many equipment OEMs bring several lines to a single show – would be much better spent sending potential customers plane tickets and picking up hotel accommodations for onsite visits to the suppliers’ demo rooms. After all, at a typical show today, few machines are operating in anything more than dry runs, and many aren’t plugged in at all. They are giant pet rocks. Kicking the proverbial tires is all a customer can do.

Equipment trade shows in our industry are not sustainable. Investing in their survival means spending thousands to chase hundreds. It’s a faulty premise, and it is only a matter of time before this dinosaur goes extinct.

Changes. A warm welcome to Bekah Just, our new production manager, and a sad, sad goodbye to the absolutely unflappable Katie Haddox who, after 12 years with UP Media (and 10 working with me), is leaving to explore California with her two dogs. Each month, Katie’s slim shoulders moved mountains to get the issue designed, laid out, printed and distributed. I wish her the best of luck, and I will miss her tremendously.

Mike Buetow is editor-in-chief of CIRCUITS ASSEMBLY; This email address is being protected from spambots. You need JavaScript enabled to view it..

Printed electronics offer the best chance for a process revolution.

The printed circuit board process has been around since before the start of WWI and has only been improved upon since the conception of etched copper traces on a single-sided substrate. Significant improvements since include:

• Etching both sides and interconnect with eyelets, realizing twice the interconnect capability.
• Introduction of the plated through-hole, eliminating the eyelets.
• Multiple layer (multilayer) construction, creating several etched inner cores, laminated with presses, then forming PTH interconnections.
• SMOBC: Solder mask over bare copper, eliminating reflow of the SnPb, allowing smaller traces.
• SMT (surface mount technology).

A multitude of packaging techniques: Buried vias, where innerlayers are interconnected with PTHs; BGAs; blind vias, where small holes are laser-formed for interconnections, etc.

All these refinements were evolutionary, as none eliminated the basic principles of chemical etching and metal finishing. Indeed, some other “improvements” have simply complicated the manufacturing process to the point where yields become a big factor. In many high-tech boards, it’s really hit-and-miss, sorting the good from the bad.

With printed electronic circuits (PEC), however, the product is reduced to four simple, repeatable steps. At every fourth step, the product can be tested and reworked, eliminating the huge scrap of the old methods. Removing complexity reduces the capital investment required by up to 80%, yet the process should be considered “green” because it eliminates the PTH. Thus, the end-product should prove much more reliable, as the interconnect is a solid metal plug instead of a thin layer of copper plating.

Applications range from the most “impossible” designs to their simplest print-only counterparts, starting from RFID to forming a circuit trace on a hypodermic needle probe. Sub-mil lines with equal spaces, and buried and blind via formation, can be accomplished with nothing more than a silkscreen press.

As packaging density increases, the potential for more reliable end-products increases, with bonuses for economic and environmental benefits. Therefore, PEC may very well become the next-generation interconnect packaging method of choice for a very large portion of electronics. Existing PCB manufacturers must get on board, lest a new startup overtake the interconnect market.

With the demise of captive PCB operations, board manufacturers that doubled as technology developers have diminished. These were the board makers that at one time pushed the PCB fabrication envelope by introducing new processes and increasing reliability. Not much remains of those players today, and those left are converters. This is sad because innovation isn’t coming from the board shops, but rather from (sometimes outlandish) customer requirements, with board shops in turn struggling to make the product. Innovations in printed electronics now involve product designers, not the layout guys, and the process is very simple.

Basic conductive inks now are available. These include a low resistance silver (4x resistance of copper) and an LPI (photoimageable dielectric), which have produced 0.001˝ with UV exposers and sub-mil lines should be possible with LDI equipment. Silver conductive ink for now will satisfy commercial needs, and we expect that R&D efforts worldwide at the university level, as well as commercial alliances, will eventually lead to a conductive nanoparticle copper ink.

Traditional PCB processes require many consumable products. For example, a drill bit might make 3,000 holes, so to build a common 25,000-hole PCB requires eight bits, at a rough cost of $16. Much chemistry is used and must be disposed of, such as dry film, excess copper and tin, plastic sheeting, release films, press pads, router bits, and so on.

By comparison, whatever is used in the PEC process remains on the board. While inks are more expensive than those used in the PCB process, the overall costs are less because a multitude of activity-based requirements are eliminated, not to mention the floor area and related costs (HVAC, lighting, etc.), power requirements to heat and cool the multiple processes, and on and on.

The PEC process is reworkable in every step, so there is no scrap. The old process banks on (the hope for) integrity of the inner traces, such as plated-hole formation, to be completely perfect until final testing is performed. In fact, a bad board is built alongside a good one, and that is a waste of money.

At the end-user level, board reliability could be improved because there is no weakness in solid metal via formation. PTH reliability, on the other hand, worsens as holes become smaller and metallization gets more difficult. With the advent of cooler solders and conductive adhesives, PEC stands to be a better product.

Is it 100% ready? Certain suppliers provide materials and process from which product can be made for evaluation purposes for the more complex assemblies. Other less-critical applications where the process can be applied abound.

Is this the beginning of the end for SMT? The answer is probably “yes,” although the timeline is undetermined.

Au.: My thanks to Mike DuBois of Caledon Controls for much of the content of this article.

Randall Sherman is president and CEO of New Venture Research Corp. (newventureresearch.com); This email address is being protected from spambots. You need JavaScript enabled to view it..

Electronics manufacturing is gone. Is engineering next?

I heard recently that another friend and printed circuit board designer who works for a company primarily known for producing large industrial and farm equipment will soon be out of a job. Yes, like many before them, the company is moving the circuit board design department offshore, in this case, to India.

While those in public relations and financial analysts will come up with nice-sounding justifications, most of us know the truth: It is a matter of dollars and cents. And meanwhile, the US continues to lose engineering know-how and expertise.

According to some, the US has already lost its technological edge to India and China. While North America still has the intellectual know-how and knowledge base, and in most cases a small physical ability to produce high technology PCBs, the capability to do so in quantity is severely diminished, if not altogether gone. Many say that the same will soon hold true in engineering. According to some of the latest information I’ve seen, the drain in engineering expertise continues. Just as the US talks about adding highly skilled, high paying jobs, the exodus continues. Even though the overall job market in the US seems to be slowly improving, engineers and scientists are two of the job functions that are decreasing, according to some reports. While I’ll admit that a lot of this may well be outside my intellectual wheelhouse, as much as I try, it just doesn’t make much sense to me. While the current administration and even the opposition talk about job creation and pitiful programs to give an employer a $5,000 tax break for new hires, I haven’t seen anything designed to stem the offshore flow of experienced engineering and scientific jobs.

As a small businessman, I understand many of the core concepts of controlling costs, and certainly realize employee overhead is a significant factor. While we can castigate certain mega-companies for sending jobs offshore, we also have to look in the mirror and realize that a lot of this is our own fault. We want these companies to be highly profitable because their profitability is what feeds our 401(k) and retirement plans. But as a CEO from a large Japanese company recently asked, “Do you want a plan for three-month profitability, or do you want a profitability plan for 10 years?” Is it really so farfetched to give US companies real tax incentives to hire domestic workers, or, heaven forbid, tax them for sending jobs offshore?

Don’t get me wrong: I am all for developing countries’ efforts toward educating their populace and developing high-tech industries to compete in the global economy. I’m a proponent of free trade. But I’m also a proponent of fair trade. However, I keep asking myself, What is the US strategy for replacing or retaining these engineering jobs? And what is the strategy for maintaining a high-tech engineering and production capability? Does the US Commerce Department or government at large even consider electronics a high-tech arena worth being in?

In a recent blog, Eric Bogatin recapped a panel session held at DesignCon in February. One of the panelists, noted aeronautical engineer and author Gentry Lee, observed a worrisome (to me) and significant trend: the decline and fall of the US as an economic power. Lee sees the engineering and design capabilities taking the same path as manufacturing – to other countries, followed closely by research and development. In his blog (http://bethesignal.net/blog/?p=72), Eric says, “There go the skilled jobs. What will this leave as the economy base for America?”

Ross Perot, during one of his many quixotic runs at the presidency, warned that ratifying NAFTA would result in a “great sucking sound” of American dollars and jobs leaving the country.

If Eric’s and Lee’s scenario plays out, the sucking sound Perot warned of will be deafening. And if I had grandchildren, instead of advising them to go into engineering or science, I’d have to teach them to ask, “Would you like fries with that?”

Pete Waddell is publisher and design technical editor of PCD&F; This email address is being protected from spambots. You need JavaScript enabled to view it..