Does Anybody Really Care?

The upside of a visible identity is that people see you can might possibly care and understand. The downside, is that people can find you. Today, I'm sort of treading the line between the two.

I'm testing out some Twitter ads right at the moment. As someone that has a service to present, I have to do things like that. Ideally, it won't be intrusive and will just give information, but that's not the point.

One of the steps in putting together a Twitter ad is to select categories of Twitter users that might be interested in what I do. The process of picking those categories reminded me of something that's almost always annoyed me when I have to pick my categories for anything. Namely, my categories aren't there.

This particular ad, is sending people to eBay to buy (hopefully) a coffee mug with the Sputnik 1 transmitter schematic on it. We're doing it to help out our local FREE GEEK place. (Yikes! Three links in a row) Again, that's not the point here.

I'm thinking that electrical engineers would be interested, as would space fans. Well, those categories don't really exist. The have a major category: "Business." The closest sub category in Business is "Technology." That's somewhat close, but do engineers really want to be classified as in the business world?

 "Careers"; nothing close in the sub categories. "Education"; nothing close. "Events" has "Tech Tradeshows" as  a sub-category, but as with business, it's not really where I'd look.

"Hobbies and Interests"? Nope. They have "Astrology", but no hobby electronics.

There's the category "Science", but its subs look like chapter headings in a sixth-grade science book.

Wait! There's "Technology and Computing"! That looks promising... But... No. It's pretty much software and IT.

And, that's it. I see this sort of thing all over the place. Software, IT and businessy stuff get categories, but electronics design, embedded computing, robotics... Other than in the direct EE press, these types of categories just don't seem to exist.

Duane Benson
What time it is?

Open The Pod Bay Doors, HASL

Does anyone use HASL (Hot Air Surface Leveling) anymore? It's also known as HAL.

Prior to the RoHS days, HASL was probably the most common surface finish. You can get it lead free, but most boards seem to use immersion silver or ENIG (Electroless Nickel Immersion Gold). HASL has traditionally come at a lower cost than those other two finishes, but immersion silver can generally be found at the same price now.

Our friends at Sunstone.com, for example, charge the same for silver and tin/lead HASL. ENIG is still more BGA on HASL closeexpensive no matter where you go though.

One of the chief disadvantages of HASL these days, is the lack of planarity on the surface. (Note the bumps on the BGA land pattern in the image on the right.) With thru-hole or large components, an uneven surface doesn't matter so much. With the increasingly smaller BGAs and QFNs, however, surface irregularities can cause big problems.

Both Immersion silver and ENIG have nice flat surfaces. OSP (Organic Surface Preservative) has a pretty flat surface too, but it's not used much except in high volume consumer goods or specialized applications.

By Duane Benson
Oh, the pain! Save me, William.

More Fun File Facts: ODB++

In my last post, I wrote about the up and coming IPC-2581 PCB manufacturing file format. While IPC-2581 may be looked at by PCB fabricators and assemblers as a holy grail of sorts, it's not yet widely adopted by CAD software. But, that doesn't mean that Gerbers are the only option.

ODB++ was developed by Valor in the waning years of the last century as an improved method for getting manufacturing data into their CAM systems. Valor and, hence, ODB++ was purchased by Mentor Graphics in 2010. ODB++ is still widely available, however there's concern in some circles that it's not truly open. That concern is where IPC-2581 came from. In fact, IPC-2581 is somewhat derivative of ODB++.

I can see how a CAD software developer might fear the use of something owned by a rival. However, my understanding is that Mentor does it's best to treat it like an open standard and has made it available more or less as though it is open.

The history isn't really important. What is important is that ODB++ is a more complete format than the Gerber and is widely supported. Pretty much everything good that I said about IPC-2581 in my prior post also applies to ODB++.

The bottom line is that, regardless of whether Screaming Circuits is your fab (through our partner Sunstone) and assembly (through our factory right here) provider, ODB++ is a good thing. It makes the job easier and more accurate than does use of Gerber files. Both "easier" and "more accurate" help keep costs down and keep ambiguities to a minimum. As you know, ambiguity is the bitter enemy of both accuracy and quality.

Unfortunately, for all of you Eagle users, Eagle does not yet support ODB++. If anyone out there is really good with Eagle ULP scripting, you might want to create a on ODB++ and/or IPC-2581 creation ULP.

Duane Benson
I was ionized, but I'm better now. 

Fun Facts About Manufacturing Files

Circuit boards live and die by their manufacturing files. Without complete and accurate information, the board fab house can't fab the boards, the assembly house can't assemble your boards and nobody can buy the parts.

Our old standard, the Gerber file, has been around since about the time King Arthur pulled the inductor out of the solder pot. It's old. We all use it because it's familiar, but it's day is done. It's time to pass the torch.

IPC-2581 is the new standard in manufacturing files. It hasn't been fully adopted, but it's showing up in more and more CAD packages. The IPC-2581 format is much more advanced and has the complete data set in one file. While we still work with Gerbers every day, we can also accept IPC-2581 manufacturing files.

I've been called the champion of bad analogies, but I'll try one out anyway.

Imagine, if you will, a map of the city. All of the streets are there. All of the houses are there. What's missing are all of the street names. No street names, no numbers and no landmarks of any sort are labeled.

Given that information, find John Smith, at 1620 SW 14th Avenue. There is a house at 1620 SW 14th Avenue. There are a dozen or so houses at 1620 something. You just don't know where 14th is, or which direction 14th runs, or where the street numbering starts.

You can physically walk each and every street until you find John's name on his mailbox, but it's not an easy nor error-safe process. And, hopefully, the town only has one John Smith. That's a Gerber file.

IPC-2581, on the other hand, is an electronic map, with everything clearly labeled, and a GPS guiding you. Which would give you more confidence?

Duane Benson
IPC-2581 is like shatter-proof glasses for Henry Bemis

The Dangers of ESD

Question:

EsdWhat do a conductive floor, foot grounding straps, conductive work smocks, wrist ground straps, foot grounding testers, ESD training, bench-top grounding monitors, anti-static bags, anti-static boxes, grounded carts, anti-static attitudes, conductive desk mats and grounded tools have in common?

Answer:

They are some of the things that Screaming Circuits uses to protect components and circuit boards from the dangers of electrostatic discharge.

Ideally, those are things that everyone handling electronic components and circuit boards would use. This is the real world, though, so there are likely companies that don't use such tools or follow good ESD control procedures. Some companies might even charge extra for what is essentially a basic right. Bad news.

Just the act of getting up from a chair can cause an in body potential of 10 kV. The human threshold for feeling a shock is around 25 kV. Silicon chips can sometimes be damaged at significantly less than that. One of the worst things about ESD damage is that sometimes the failure mode doesn't show up until the device is out in the field.

One of our many missions here at Screaming Circuits is to keep the dreaded ESD monster away from your boards. Your PCBs and your trust are very important to us.

 

Duane Benson
"Zero potential" is bad when when coming from
your parents talking about career prospects.
But it's good when evading ESD.

Let's Get Small, as in 0.3mm

Not long ago, I wrote about a 0.3mm pitch wafer scale BGA we received and were asked to place. The gist of that article was that those parts are very small and we d0n't yet have a process that we feel will give the quality, reliability and consistency that we want to deliver. That means officially, we don't, at the moment, support that form-factor.

However, as it turned out, we went ahead and built it and the x-rays all said it looked good. Whew! We still don't officially support it, but we're working on it. If you have one of these things, you can always give us a call and see if it's something our manufacturing engineers are comfortable with. If they say "sure, send it in", It will be a non-standard, essentially, experimental, operation so our normal guarantees won't apply. It will be "we'll do our best."

But that's not the point. The point is that there are still a number of unanswered questions with 0.4mm pitch, and now we have a smaller one??!!

I've only seen 0.3mm pitch in two places: some data from Amkor, and the data sheet for this part.The part in questions is a Maxim MAX98304 Mono 3.2 Watt Class D amplifier. The entire package is just 1mm x 1mm.

There is still a lot of difference of opinion on solder mask defined (SMD) vs. non solder mask defined (NSMD) at super small pitch like this. For BGAs 0.5mm and lager, the general consensus and IPC recommendation is NSMD. At 0.4mm, the Beabgleboard folks at Ti recommend SMD to reduce bridging. But I've had other folks say they get good results with NSMD. For 0.4mm, we've had best results with SMD. It's more than just that though, you also need to religiously follow the manufacturer's recommended pad sizes and such.

Shrinking BGA pitchFor this part, the datasheet shows the pad size (0.18mm), but doesn't cover the SMD vs. NSMD question. Instead, it refers to a Maxim app note (#1891) for that bit of information.

Of course, this is where it gets sticky. That app note, as of this writing, shows 0.5mm and 0.4mm, but no 0.3mm. It does reference IPC-7351, which is a very good thing, but I don't think IPC-7351 has 0.3mm pitch covered yet. Ugh. The 0.3mm part we placed used SMD pads.

Duane Benson
It's not just Facebook where you can designate something: "It's complicated."

 

It (.3 mm) Finally Happened

Back in January of 2012, I wrote about the possibility of 0.3 mm pitch BGAs being used here and there. I predicted that in a year, we'd see some 0.3 mm pitch BGAs showing up. I was about three month's off. Almost to the day.

I delivered a session at PCBWest last month and asked if anyone had used a part with that pitch yet. One hand went up. That actually surprised me. What surprised me even more was when one of them (a .3mm pitch BGA, not a hand) arrived on our shipping dock in a parts kit earlier this week.

0.3mm pitch trimFor comparison, the land pattern for an 0402 passive component is about one millimeter long. This specific part is just shy of a millimeter square. Even as small as it is, this part can supply 750 mA continuous. The olden days are so very long gone.

We do many, many complex parts and PCBs. We've put 5,000 parts on a single PC board. We've built boards to be shot up in rockets and dunked way down in the ocean. Some very crazy stuff has come though our shop, but we don't do everything. We don't do 01005 passive components at the moment. Our machines have the technical capability, but we don't rework them, which has to go along with the assembly capability, so we don't support that form factor for now. 0.3mm pitch components pretty much fall into that camp. Our machines can physically pick up and place the component, but until we've developed to process to assemble those parts with the quality people expect from us, we won't be supporting them.

I expect we'll be getting more and more requests for the form factor, so we'll be looking at it. Keep checking back. One of these days, we'll have the process down and reliable.

Duane Benson
It's (Huey mm, Dewey mm, and Louie mm)/10

To Mod or Not to Mod? That is The Question

Many years ago, I was a product manager at a business-consumer electronics company developing some pretty leading edge display equipment. Prototyping back then was a long and painful process. A PC board might take a month or two to arrive from fabrication. Parts had to be sourced by digging through massive catalogs and then hoping that what you needed would be on the companies approved vendor list. The whole process was a bear.

Well, the soldering up part wasn't always so bad - unless you were the poor soul tasked with wire-wrapping or hand soldering the prototype.

Based on how difficult and expensive a board spin was back then, common practice was to just mod up the boards, even in production. Any given PCB might have a dozen or more cuts and mod wires. Those changes might not make it into the PCB for months. These days, though, you can get board fabbed Mod wireovernight, your parts delivered over night, and when you have all of those parts and PCBs, you can get them assembled overnight. I suspect that increase in speed is the major reason mod wires seem to be nearing extinction these days. (note that Screaming Circuits didn't build the board in this picture. It's from my personal collection)

It may not seem cheap to pay to have someone re-spin a board so speedily; especially when set next to hand soldering. But when compared to the cost of idle engineers waiting for the next rev, the cost of adding mods, the reduced reliability from having mods and the additional manufacturing time caused by modding a board; today's quick-turn parts, fab and assembly options can end up saving gobs of time and money in the long run.

Duane Benson
There are more wires in heaven and earth, Horatio, Than are soldered on your pc board.

Ode to Competition

Thanks to Theodore Roosevelt, we almost all have competition of some sort or another. I'm not a big fan of the statement made so often: "We welcome the competition, It validates the market." or similar such sentiments. You usually hear that from a spokesperson when a new competitor enters the market. My guess is that most people who say that are probably thinking to themselves: "Yeah. In a pig's eye" while stating it.

Theodore RoseveltI'm also not a big fan of the phrase so often heard in start-up companies: "We don't have any competition." To me, that's a warning sign. You might not have much competition, but you always have some. At minimum, other companies (maybe even with non-competing products) are competing for the same dollars. If someone thinks they don't have competition, I would suggest they look a little closer at what their customers need and are doing.

The number three statement that I'm not a big fan of: "Imitation is the fondest form of flattery." I do understand it. If someone is copying you, that must mean that you're doing something right (the possibility of the blind leading the blind not withstanding). In a business context I do believe that all three of those statements are a form of saving face. You can't stop competition from showing up, but you can pretend to be noble and welcome it. It's not always possible to stop people from copying you, but you can pretend it's a complement.

Here's what I think about competition: It's my job to give you better value than our competition. Plain and simple. If you come to me for business and I give you better value: What you want, when you want it at a fair price, then I have earned your business. If a competitor gives you better value, it means that I'm not doing my job right. We are all in this to make money, but we're in this to make money in such a way that we are the best value for you. Not the lowest price, but when you add up our reliability, quality and technical capabilities, doing business with us should save you time, aggravation and money.

So why the maefesto? It annoys me when competitors place comments on our blog linking to their website. Especially when they don't identify themselves. Yes, it means that they believe that we are doing things right. Yes, it means they think we have enough customers that it's worth trying to lure some away from us. So, in a sense, it is validation that they think we're doing a good job. I don't really see that form of "validation" as being worth much though. What I really care about is that the people who give us money think we're doing a good job and that they get their money's worth.

Duane Benson
We are with you, sire! For Sparta, for freedom, to the... to the... Um...
to the sucess of your project!

Who Are You?

A lot of events are preceded with a "meet and greet" session. It gives you something to do for an hour or so before the real activity takes place. I'm not much of a schmoozer myself, but if the crowd is right, there is value in the activity. It's good to get to know folks with similar interests or vocations.

On the Internet, Facebook is kind of known as the place for that sort of thing. The problem with it though is the low signal to noise ratio. Too much drivel to sort through to find the valuable nuggets. But Common ground 0402s schdon't despair. All is not lost. Over at EEWeb, they have something pretty close in their "Featured Engineer" series. As of this writing, they have well North of a hundred profiles. Peruse through and get to know some or the people making things happen in the world these days.

If you look close, you can find yours truly in the list. And the first person to name the science fiction movie I'm thinking about gets a free Screaming Circuits polo shirt. The first person who can correctly identify the lighthouse gets one too. (the lighthouse is small in the photo, but if you've been there, you'll recognise the area) Only in the U.S. though. Sorry, but customs gets me down so I'll only ship to a U.S. address. It might not be the same shirt I'm wearing, but close.

Duane Benson
In life I was your partner, Jacob Marley.