Screaming Circuits: Industry

What is Personal Manufacturing?

There's a lot of buzz floating around these days, about "Personal Manufacturing." Screaming Circuits has more than a decade of bringing personal manufacturing to engineers. We pretty much started the category in the electronics industry, so we're quite familiar - but not everyone knows what personal manufacturing is. I'll do my best to describe it, and what it can do for you.

The short answer, is that personal manufacturing is building your boards on your terms, not on the terms of some nameless, faceless factory.

The longer answer is probably more useful. 

Traditional manufacturing is all about statistics and fractions of a penny. Those factors are important; especially if you're manufacturing millions. But, when you just need a few boards, or a few hundred boards, those factors can make your job nearly impossible.

With personal manufacturing, you can decide when you want or need assembled boards on your workbench. You won't need to beg for time on a busy volume manufacturing line. In the case of Screaming Circuits, it's cloud-based manufacturing so you can order online from your desktop, when you're ready, rather than waiting for someone to pick up a telephone.

With personal manufacturing; you design it, get some prototypes, make a few mods, lather, rinse, repeat. Then, you'll get a few dozen, few hundred, or few thousand, and start selling. You'll get what your budget allows and don't need to commit to minimum volumes, or long-term business. You can polish your design faster, with less hassle, and you can get to market faster, with less hassle. Faster to market and less hassle both mean more time and money for you.

NPI (new product introduction) has never been easier than it is with personal manufacturing. Years ago, I was a product manager at a start-up. The entire NPI process was a nightmare. Our engineers couldn't get anything built without half a dozen support staff. Someone had to make the documentation usable. Someone had to hunt down sample quantities of parts. Someone had to make sure the board would fit on the volume manufacturers' assembly line. It went on and on like that, taking up months of the design cycle. We were at the mercy or people who only cared about making their part of the process easier.

Rather than producing the quality product we wanted, our new products would be shipped to customers with mod wires. I recall one board that needed 64 mod operations before it could be shipped. Yes, that was on a released, shipping product.

With personal manufacturing, as Screaming Circuits provides, you can get a few prototypes built right away. If need be, you can modify, and get a few more built at your convenience. When the mode wires are gone, you can build up a hundred and get them out to customers without delay. It's not about what works best for Screaming Circuits; it's about what works best for you.

Duane Benson
Right now a personal pan pizza delivered to my desktop would work for me.



Manufacturability Index in practice

My prior blog covered the Screaming Circuits Manufacturability Index. It's something I'll be using from time to time when discussing new components I run across. I've got a few examples to put the numbers into context.

On the low side of the index, we have:

7400 TH1: Just about anyone could hand solder the part
Examples: Thru-hole parts

The SN7400 quad NAND Gate, shown on the right, is a good example. It's big, it's thru-hole, and if someone has trouble hand soldering it, they really need a few more classes.

Closer to the other end, is a new chip I've run across. The Silego GPAK4 is a small FPGA-like mixed signal device. It's got a number of analog peripherals, a bank of programmable logic, and the ability to configure it up the way you want. Take a look at it below:

GreenPAK4 cropped

This little thing is housed in a 2 mm X 3 mm QFN package. That's pretty tiny by the standards of my giant fumble-fingers. I've given it a rating of 4.b, on the Screaming Circuits manufacturability index. The number ranking "4" means: "Needs advanced automated assembly technique", and the letter suffix "b" means: "Typical level of challenge within the number rank." In other words, right up our alley.

Unless you posses super-human abilities, and maybe lasers in your eyes, you won't be hand soldering these. You'll have them assembled by us (or someone with the same technical capabilities as us), where it will be a standard process.

If you do want to put one or more of these in your design, you will want to make (or find) a custom library footprint for your CAD software. Due to the variable length pads, a standard one-size-pad footprint might lead to solder joint reliability issues.

Duane Benson
The chips go marching one by one, hurrah, hurrah
The chips go marching one by one,
The little one stops to suck her thumb
Just to see if the solder is lead-free


Screaming Circuits Component Manufacturability Index

Screaming Circuits Manufacturability Index

Ranks the difficulty of assembling a component. Index is one to five, with one being easiest, and five being the most complex

Sub index: a, b, c

    a: Not a challenge within the number rank
    b: Typical level of challenge within the number rank 
    c: Fits in the ranking, but likely needs special process, fixtures or attention

1: Just about anyone could hand solder the part
Examples: Thru-hole parts

2: Surface mount. Should be machine placed, but big enough to hand solder
Examples: 0805 or larger surface mount passives, SOIC packages

3: Pretty much any grade of surface mount equipment can handle this component
Examples: TSSOP or larger, 0.8mm pitch BGAs

4: Needs advanced automated assembly techniques
Examples: 0.4mm pitch BGAs or QFNs, CSP (chip scale package) or WSP (wafer scale package) BGAs, 0201 size passives, Package on Package (POP)

5: More or less R&D at this point. Few companies have or will assemble this part
Examples: 0.3mm pitch micro BGA, 1,700+ ball BGAs, 01005 passives

Just about everything 4b, and below are routinely within Screaming Circuits standard (guaranteed) process. 4c, 5a, 5b, 5c, are becoming more common here. These are special process (falling outside of our guarantee), but we can usually do a good job with them. You'll need to speak with a manufacturing engineer before placing the order.

Duane Benson
a colossal negative space wedgie of great power coming right at us at warp speed
Readings are off the scale, captain

Internet of Things Month

I’m not sure exactly when the term “Internet of Things” (IOT), was coined, but it’s become one of the hottest topics in the electronics industry. The IOT is all about connected devices, most small and independent; many from makers and new start-ups.

In the IOT of the near future, virtually every household, office, and personal device will be remotely controllable to some degree. And, it’s not just about control. Most of those devices will also sense conditions, respond, and communicate appropriately.

If you were to take a tour of our factory floor today, and compare it to a tour of a few years ago, you’d, of course, see more large boards loaded with complex components. You’d also see a lot more super small boards crammed with microcontrollers, wireless communications, sensors, and tiny parts. Many of them are no larger than a US quarter. Those are Internet of Things devices.

The number of different devices being churned out is staggering, yet is a trivial number compared to what we’ll see in the next few years. Scoff, if you must, but there will come a time when your favorite ball-point pen can let you know just who stole it off of your desk and where they've hidden it.

In honor of the spirit of innovation brought forth with the IOT, Screaming Circuits has declared April 2015 to be Internet of Things month.

A_small_cup_of_coffee 250You too may be able to join in the celebration by placing an assembly order during March 2015 and requesting our “Internet of Things Gone Bad” poster: a contrarian view into a possible dystopian world where humans have to argue with their clothes, coffee pots, and cars, before leaving the house.

If you places an order with us in March 2015, will get an email asking if you want out Internet of Things poster. Just reply in the affirmative, and we'll send it out to you.

Duane Benson
All things on the Internet are relative
All my relatives are things
My relatives took all of my things

Do you need PCB Assembly Services?

Do you need PCB Assembly Services, or do you not? That is the question. Well, it's A question. Just one of many, I suppose.

TI TPS62601 front and backOne of many, but it is a question just about every electronics developer needs to answer at some point. The answer isn't always yes, nor is it always no. The answer is quite often "It depends." I work here and I don't always have a clear answer to the question. I've sent some board through our plant, and have hand built a few.

For me, it comes down to a few options:

Use Screaming Circuits PCB Assembly Services:

  • Does it need to be done right?
  • Is time a consideration?
  • Are there too may placements for me to deal with?
  • Are there more than one or two boards?
  • Are the parts too small?
  • Are there any BGA packaged chips?
  • Will it be monotonous?

Build it myself if:

  • It's a no-hurry project.
  • The parts big enough.
  • It be fun.
  • It will be a valuable learning experience.

I can enjoy building up a board myself in the same way that someone working for a car manufacturer might rebuild cars at home as a hobby. 0805 passives aren't a problem for me to hand solder. I don't mind a small number of 0603's. I'll hand solder 0402's in a pinch. I've tried a few 0201's with poor results.

Forchips, I don't have a problem with SOIC's. I'm not bad with a TSSOP. QFN parts are a challenge, but some types have enough exposed metal on the side to solder. I really can't place BGA's, but I'm experimenting to see if I can find a way to solder small ones in my toaster oven.

With the impending advent of desktop pick and place machines, there will be a few more options, but the basic question will remain the same as it is with "build vs. buy" in any industry: "Which do I have more of, time or money?"

Duane Benson
Let's get small!

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, 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


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?


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.