We are pleased to share that PCB Chat, our popular podcast, is now available via Spotify.
So now you have four channels for accessing the weekly podcasts: iTunes, Google Play, Spotify and, of course, pcbchat.com. Happy listening!
Asian media are reporting that major Taiwanese ODMs are looking into relocating some production to the island as means to sidestep the US tariffs on imports from China.
DigiTimes reported today that Quanta Computer and Wiwynn are among those looking to avoid new duties on server-use motherboards, which represent a major product line for both ODMs.
Quanta builds server motherboards in Shanghai, then performs final assembly in Nashville, TN, and Fremont, CA, and Wurselen, Germany. Executives say the company might expand production outside China to make up for any domestic reduction.
Wiwynn, which is part of Wistron, also has production in China. It performs performs final assembly in Mexico.
Question: With China increasingly flexing its authority over Taiwan, will moves by companies in the critical technology space accelerate or exacerbate Chinese claims to Taiwan?
Our latest episode of PCB Chat is with Z-Zero founder and “director of everything” Bill Hargin. Z-Zero is the newest entrant in the EDA field. The company this year rolled out its first products: software tools for PCB stackup planning and material selection. He speaks with Mike Buetow about the company and new tools.
Soldering copper to copper with a tin-based solder, such as tin-lead eutectic solder or a common lead-free solder like SAC 305, requires only the liquid solder and copper to form the tin-copper intermetallic bond. This simplicity, with one small catch, was brought home to me by some colleagues at Speedline Technologies. They took a PWB with through-hole components mounted and ran it through a wave-soldering machine without using any flux. The result was comical. The PWB weighed about 10 pounds as it had huge solder ice cycles hanging off of it. Oxides that form on the copper created this mess. Running the board though again with a nitrogen blanket produced a beautifully wave-soldered board that could be ready to ship. So in reality, either a flux or nitrogen, preferably both are needed for successful wave soldering in addition to the solder and copper; however, it is still relatively simple.
Have sympathy for the solder scientists of the late 1970s and early 1980s. SMT was an emerging technology and the world wanted to buy solder paste; however, the only experience many solder scientists had was with wave soldering. In wave soldering, the flux’s main job is to remove the oxides from the PWB pads and components. The solder is in a molten state and its oxidation is not a main concern. In the soldering process, the solder only touches the board for a few seconds and the board only experiences the high temperatures during this brief period.
I imagine some early solder pastes consisted of solder powder with fluxes similar to those used in wave soldering. If so, they probably didn’t work too well. Consider the dramatic differences that solder paste experiences as compared to solder in wave soldering. The “flux” in solder paste has to remove oxides from the PWB pads, component leads, and solder particles, but it also has to protect all of these surfaces from re-oxidation for several minutes while in the reflow oven. To achieve this protection, the “flux” has to contain materials that act as an oxygen barrier. The most common materials used in no-clean solder pastes are rosins/resins. Rosins, or resins which are modified or synthetic rosins, are generally medium to high molecular weight organic compounds of 80-90% abietic acid. They are typically found in coniferous trees. Rosins/resins are tacky in nature, and provide some fluxing activity and oxidation resistance during the reflow process.
The reason I wrote “flux” in the above paragraph is that what most people call the flux in solder paste is a complex combination of materials. These “fluxes” will consist of:
Modern solder pastes must have good oxygen barrier capability. In most reflow profiles, the solder paste is at temperatures above 150ºC for more than several minutes. During this time, an oxygen barrier is needed to protect both the solder particles and the surfaces of the pads and leads.
A common example of an insufficient solder barrier is the graping defect or its relative, the head-in-pillow defect. If you are experiencing one of these defects, a solder paste with better oxygen barrier properties is bound to help.
Before reflow, the solder paste must print well, possess good response-to-pause, not shear thin, resist cold slump, and have good “tack” to support the components after placement. During reflow, in addition to the oxygen barrier challenge, the solder paste must not exhibit hot slump, should “Avoid the Void,” not create the “head-in-pillow” (HIP) defect, work with all common PWP pad finishes, and produce reliable solder joints in thermal cycling, drop shock, and vibration environments. Whew! What a complex challenge.
As a result I would argue that solder paste is a candidate to be the most highly engineered material in the world… and it certainly is NOT a commodity.
The breaking tariff situation in the electronics industry is equal parts fascinating and chilling because of its lack of near-term precedence and unpredictability. We’ve spoken with several EMS companies (read the article here) to gauge the extent of the disarray and get a sense of how they are (attempting to) resolve the issue.
Our reporting is ongoing, so be sure to check back occasionally for updates.
How to Maximize Your Value to the Boss
Jerry wasn’t your average engineer.
While his college classmates fascinated on academics, Jerry raced down the sidelines snagging sizzling passes for the Baylor Bears. Soon he scored a much sought after intern offer from NASA and bought an acoustic guitar to serenade the boot scooters. What could have been more thrilling than to see an inspired young man from Shreveport, LA reaching for the stars and achieving success?
But, ultimately talent is finite, youth is fleeting and good looks are quite common.
As he rose through the corporate ranks, the traits that made Jerry his company’s most valuable player year after year had little to do with his athletic prowess or his love for a catchy tune. Jerry’s secret formula was his priceless perspective. His worldview.
Jerry thought like a business leader. Every day. In every situation. And when the opportunity presented itself, Jerry overcame all the challenges of an economically distressed childhood to buy majority ownership in his company. Jerry thought like an owner and became one.
Could you do the same? Could you propel yourself into another universe by changing the way you approach your job. We believe you can. We hope you will. But, hope is not a strategy.
As it turns out, there is no average engineer. There are only engineers who think like employees and engineers who think “like a boss.” The daily choices you make are indicative of the path you’re on. So test yourself while there’s time to adjust and ramp up your game.
Here are 12 questions you can quietly ask yourself to predict your outcome.
True or False:
_____ I do what is right for my customer, company, and team regardless of personal sacrifice.
_____ I press forward with good ideas, even if they are unpopular.
_____ I aim for goals higher than any manager will set for me.
_____ I do not give in to group pressures simply to avoid confrontation.
_____ I consistently give truthful feedback to customers, superiors, and teammates.
_____ I adhere firmly to a code of business ethics and moral values.
_____ Change always brings opportunity. Stagnation limits opportunity.
_____ I practice a disciplined approach to self-improvement.
_____ I have a method for prioritizing my opportunities today.
_____ I successfully make others enthusiastic about opportunities that require extra effort.
_____ I transmit a sense of purpose about all that I do.
_____ I am accountable for my actions and accept responsibility for my mistakes.
If you answered true to nine or more of these statements, you are on the right road to wind up steering your own endeavor. If you answered false to three or more of these statements, you’ll likely always report to someone else. It’s all a matter of your objectives.
Jerry knew from early in life that he wanted to reach his full potential, whatever that might be. I have no doubt that if you asked him today, he’d tell you that he’s still in the relentless pursuit of excellence. In other words, he isn’t done! He’s still streaking for the goal line.
Baylor University recently built a stunning new stadium in Waco, TX, with world-class amenities. On any given Saturday night, you’ll find Jerry up in the stands. His heart is always in the game. And if you wander up to Jerry, ask him if you should aspire to own your own company. He will likely chuckle, wish you much success and suggest that you will have to make that decision for yourself. But regardless of your goals, Jerry will say, “be the best YOU that you can be.”
Keith Martino has a passion for helping engineering executives achieve stellar results. Martino authored the book Expect Leadership in Engineering. In addition, the team at Keith Martino has designed and launched Leadership Institutes at multiple engineering firms across the US. Martino is quoted in Young Upstarts, Entrepreneur Magazine, NewsMax Financial, the FedEx Worldwide Manager’s Pak, and several metropolitan business and industry trade journals. For more information visit keithmartino.com.
Pity Ötzi, The Iceman, circa 3500 BC. It is believed that he was involved in copper smelting as both copper particles and arsenic, a trace element in some copper ores, were found in his hair. Not only was he being slowly poisoned by the arsenic, but to smelt the copper he had to achieve a wood fire temperature of about 1085ºC (1985ºF), as discussed in my last post. The arsenic in the copper did have a benefit, as it gave the copper a little more strength than if it were pure.
Shortly after Otzi’s time, metal workers discovered that adding 10% tin to the copper produced bronze. Bronze is not only markedly harder than copper, but it melts at almost 100ºC lower than pure copper, making metal working much easier. The Bronze Age had begun. This period coincided with what scholars would recognize as the beginning of modern civilizations, such as those in Egypt and Greece.
Since it melts at a lower temperature, bronze also fills molds better. This improved mold filling is evident in Figure 1. This photo shows a copper and bronze hatchet that I had made. The copper hatchet on the left shows evidence of poor mold filling.
In my opinion, it is almost certain that the Bronze Age is related to the development of soldering. The first evidence of soldering was about 3000º BC where, arguably the first civilization, the Sumerians assembled their swords with high temperature solders. Since the base metal for most copper-to-copper soldering is tin, the early metal workers almost certainly learned that tin could be used to join copper or bronze pieces together at much lower temperatures than smelting.
Until the European Union’s restrictions on lead in solders in 2006, most electronics solders were tin-lead eutectic. Eutectic is a Greek word that roughly translates into “easy melting.” Figure 2 shows the tin-lead phase diagram. Note that the melting point of tin is 232ºC and that of lead is 327ºC, yet at the eutectic concentration of 63% tin/37% lead, the melting temperature drops to 183ºC. This concentration and temperature is known as the eutectic point.
After the EU’s lead restriction went into effect, most electronics solders are based on a tin-silver-copper alloy that melts in the 217-225ºC range. The most common of these alloys being SAC305 (Sn96.5Ag3.0Cu0.5, where the numbers are weight percentages.)
Although the eutectic point is an interesting and usually beneficial phenomenon due to its lower melting point, the true miracle of soldering is that two pieces of copper that melt at 1085ºC can be bonded together with a tin-based solder at less than 232ºC. The value of this benefit cannot be overstated. Nature has allowed us to mechanically and electrically bond two pieces of copper together at a low enough temperature that we can do this bonding in the presence of electrically insulating polymer materials. Without this feature of solder, we would not have the electronics industry! An added benefit is that the bonding is reworkable, so that if a component fails, it can be replaced without scrapping the entire electronics printed circuit board.
It is natural to ask how this bonding takes place. The tin in the solder forms intermetallics with the copper. Typically Cu6Sn5 forms near the tin and Cu3Sn forms near the copper (Figure 3).
So next time you use your smartphone, laptop, tablet, or other electronics device, don’t forget that without the miracle of soldering it wouldn’t exist.
Soldering is an ancient technology. It is estimated that soldering was first discovered as long ago as 4000 BC. So soldering was much more ancient to Julius Caesar (100 BC – 44 BC) than Caesar is to us today. Before considering soldering, let’s discuss early copper smelting, as copper is usually the metal soldered to.
My Cornell colleague Steve Sass wrote a book, Materials: The Substance of Civilization, on which I based my course of the same name on. In his book, Sass points out that the importance of the firing of clay can’t be overstated as it is the first time humankind changed the nature of a material. Once clay is fired it forms ceramic, a material much stronger than dried clay. Artisans first performed this feat about 26,000 years ago in what is now the Czech Republic.
While I agree with Sass’s assessment, it could also be argued that the beginning of modern technology can be traced back to the first smelting of copper. The firing of clay is too simple a process to encourage much further experimentation, which is needed for technology growth. The process of smelting of copper, the first metal liberated from its ore, is quite complex and this complexity led to further experimentation that gave us iron and steel. Continued working with metals likely developed the scientific method, hence led up to all of the breakthroughs to this day.
Consider the novelty of the first smelting of copper. To smelt copper, our ancestors had to grind copper ore, malachite (Figure 1), into a powder, mix it with carbon, and heat it to greater than 1085ºC (1985ºF). By the way, you can estimate the Fahrenheit temperature by multiplying the Celsius temperature by a factor of two and will only be off by <10% from 100º-1700ºC.
After I cook on my outdoor grill, I clean the grates by turning the propane to maximum to cook off the grease. Typically the grill’s thermometer will read about 600ºF during this process. The grill gives off so much heat that it is oppressive to approach it to turn it off. Needless to say, noting what 600ºF feels like suggested to me that it is very hard to achieve 1985ºF with a wood or charcoal fire.
Anyway, I recruited some graduate students to try and smelt copper as described above. They purchased many bags of charcoal, used a leaf blower to supply air and worked for two hours on two different attempts and failed both times. The next year some students built a tower with vents and put charcoal on the bottom with the copper ore and carbon in a crucible on top. Their tower was similar to a roman smelting furnace for iron (Figure 2). They were successful and produced a piece if copper about the size of a penny.
These two attempts demonstrate how amazing our distant ancestors were. How did they think to do it? There were certainly many failed attempts. How did they persevere? One thing is certain, they started the trend of discovery, in about 5000 BC, that led us to today. We owe them much.
The evolution of the EMS company as a “brand” is nearly complete.
Since a group of industry folks (including our columnist Sue Mucha) came up with the term at an industry meeting more than 25 years ago, the once common jargon of “board stuffers” has been vacated. In its place, the industry substituted CEM (contract electronics manufacturer) or EMS (electronics manufacturing services). Contract assembler, while still commonplace in conversation, is less preferred in writing, especially on corporate websites.
Now, the self-branding of EMS companies has taken over. No longer content with being grouped as an industry, EMS firms are taking matters into their own hands, outsourcing (get it?) their marketing to high-profile branding firms and adding a heavy dose of pizzazz along the way.
One well-known makeover is the company formerly known as Flextronics. Its style experts gave a haircut to its name (“Flex”), and added a sleek tagline: From Sketch to Scale.
Not to be outdone, Jabil is “A Trusted Product Solutions Partner+.” I’m not sure what the “+” means, exactly, but maybe it has something to do with Jabil’s alternate slogan: “Empowering Brands / Empowering the World.” That sounds exhausting.
Asia is getting in on the act. Wistron will serve you “Cradle to Cradle.” (That refers to the lifespan of electronics, but if my kids’ habits are any indicator, it could extend much further.)
Compal‘s catchphrase leans toward the esoteric: “From Vision to Reality.” If that’s too vague, the rest of it (“Innovation Empowered”) won’t help.
Tier 2 companies are also jumping on the bandwagon. Neways is now “Your EMS Lifecycle Partner.”
Of course, not every firm has caught the branding wave. For instance, AsteelFlash is Electronics Manufacturing Services, Mastered,” while NeoTech is taking a more traditional approach with its slogan, “Providing Electronics Manufacturing Services That Deliver Value.” Someone better clue them in, stat.
Most of the electronics design world is by now aware that we’re in a very serious period of components shortages. Hardest hit seem to be ceramic capacitors, but other passives as well as a variety of connectors and silicon parts are also caught up in the shortage storm. Allocation and shortages hit every few years, but this one seems to be the worst in recent memory. It could be a problem until 2020, and the supply chain and world of components manufacturers will likely be a different animal coming out of it.
So, you might ask, isn’t that just a problem for high volume producers? No, I would answer. It affects anyone regardless of volume. The exact way that it hits you and what you can do about it may differ, but it has or soon will hit all of us.
Here’s five things you can do to minimize the effects. I’m going to go backwards and starting with the most important thing for people who need low volumes manufactured:
1. Check the availability of all of your parts immediately before sending us your bill of materials.
The. very. last. thing. before sending us your BoM. It’s not uncommon for a part to be in stock one day and out the next. We’ve even seen cases where the part’s in stock in the morning and out by the afternoon. If you’re having us quote and order your parts, verify they are in stock as the last thing you do before sending your files to us.
Almost every BoM we see these days has one or more parts that are out of stock. We send you an email about the parts being out of stock. We can’t do anything else until we hear back from you. We can’t build without parts and we don’t know your design like you do, so we can’t guess at substitutions. A last-minute check can save days of delay.
2. Put one or two alternate part numbers in your BoM, especially for passives.
As I said above, we don’t know your project so we can’t pick a sub for you. Give us some alternates. Put them on the same line as the original part, to the right. And be sure to tell us in the special instructions that you’ve put alternates in the BoM.
3. Consider your parts values carefully. You may be able to pick something with better availability.
The 0.01?F capacitor is the hardest hit component. It’s the most commonly used bypass capacitor. Some designs need exactly that value, but many don’t. It may be easier to find a 0.022?F, a 0.0047?F, or something else close enough. If that’s the case, choose a close enough value that has better supply, or put one in as an alternate.
4. You might need a slight redesign to use a smaller package.
Since smaller packages can be used in more applications, many suppliers will be allocating more of their foundry capacity to smaller form factors like 0402 and 0201 sizes. Some component manufacturers have said they’ll be permanently discontinuing anything bigger than 0402 parts except when absolutely necessary.
Stick with 0402 size passives. It may be easier to find the parts you need in that package, and those size parts will be the first ones to come back in stock.
5. If we send you a message about a part we can’t find, respond as quickly as possible.
We do our best to avoid any delays in this process, but we can only do so much. Help us out by getting back to us as soon as possible, and don’t be afraid to give us more than one part number to try.
This can be a pretty annoying problem and it can cause delays and other problems. The good news is we’re having this problem because the design world is booming and technology is advancing. It will get better, and following these five tips can help prevent delays. Don’t forget to check your parts for availability right before sending your BoM in to us. I mean it!
Parts, parts everywhere, but not an 0805 to solder