Blog - Screaming Circuits

An Engineer Entrepreneur’s First Brand Lesson

If you’re an engineer starting a business, do you need to worry about your business’s brand?

In a word: yes.

You don’t need to make a big project out of it at the start. It can be as simple as a collection of notes. But simple or complex, you really need to start right away. Doing so will make things much easier down the road. The nice thing is that you can get started quite small. You don’t even have to call it a plan. At this point, it can just be a vision. (If the word “vision” seems too buzzwordy, then just call it “a bunch of ideas”)

What is a brand?

A brand has a lot in common with a person’s personality and reputation. It’s close enough that you can think in those terms. And, think, you should. Think about what you would like people (customers, employees, friends, family, etc.) to think and feel when they hear your company’s name.

What personality do you want your company to have?

  • Are you mean and gruff?
  • Are you nice?
  • Quiet?
  • Loud?
  • Helpful?
  • Athletic?
  • Sedentary?
  • Reliable to a fault?
  • Usually reliable?

Will you strive to be perfect, just okay, or a bit better than “good enough”? Do you want people to see you as having the best technology, or the best price? Go on with questions like that. Write down your questions, and write down your answers. You can carry a small note pad and pen around, but I suggest that you use a memo application on your phone. You’ll always have it with you, and it’s quick and easy to use.

When you walk into a grocery store, look at the signs. Do they strike you as inviting, or cold? When you get new tires for your car, watch how you’re treated. When you order parts online, consider how easy or difficult the web site is to use. Will any of that, or something similar, apply to your business? If so, jot down a quick note about it. Make a note any time you see or think of anything that triggers thoughts of what you want your business to be like.

You’ll collect all of these notes and clean them up a bit. These will become your brand attributes. They are the seed of a brand for your company.

Once you have this seed, you’ll use it to guide business decisions – all of them. For example; if financially frugal is one of your chose attributes, you won’t go out and rent a big office with mahogany paneling. If you want to be seen as leading edge in the media world, you might buy Mac laptops instead of clunky desktop Windows PCs.

Every thing you do and say, all of the time; it is all part of your brand.

A few example notes:

  • Am I cheap or expensive? Neither – I just want people to feel like they got a bit more than their money’s worth.
  • What about flashy? A little, but only where relevant. I don’t want fancy boxes, but I want them to look befitting of new technology.
  • I’m selling to engineers in banks, so casual suits if I’m in the front office, but no suits when I’m not.
  • Do I want people to envy my lifestyle? No, I want them to see me as a crazy workaholic.
  • What about getting in touch with me? I don’t think phone support is necessary for all of my customers, but I think email should be answered within an hour.
  • Am I “big industry”? No. I’m nimble and “new economy.” I should get a small office in a recently gentrified part of town, instead of in a mid-city office building.

Keep going. It can be as simple as that. You can get more formal and organized with it later.

Veterans Day 2015


To those who make and have made our freedom, our successes, our failures, our petty arguments, our philosophical differences, our explorations, our livelihood, our great discoveries, our day to day accomplishments, our freedom... To those that make and have made this all possible, the people at Screaming Circuits thank you.

How Should You Mark Your Diodes?

Current flows through a diode from the anode to the cathode - it will pass current only when the potential on the anode is greater than the potential on the cathode. This is mostly true, but not always.

For the common barrier diode, or rectifier, it's a pretty safe bet. However, with a zener diode, or  TVS, it's not true. And, that is why marking a diode, on your PC board, with the plus sign (+) is not good practice.

Take a look at the schematic clip below.

P-Mosfet and barrier diodes

Once you put this circuit on to a PC board, you could legitimately place a plus sign on the anodes of D3 and D4, and another on their cathodes. In the next schematic clip, you could legitimately place both a plus sign, and a minus sign on the anode of D9.

Flyback diode configuration

We don't know what you had in mind, and, we don't have the schematic. If you use the practice of marking diodes with a (+) on the anode, we don't have any more information than if you didn't mark it at all. The same holds for using a minus (-) sign. It really doesn't give us any information.

Diode markingSo how should you mark your diodes? The best method is to put the diode symbol next to the footprint. on the PC board, as shown below. You can also use "K" to indicate the Cathode, of "A", to indicate the Anode. "K" is used because "C" could be mistaken for "capacitor."

D5, in the illustration on the right would be the preferred method. D7 will work as well. If you don't have enough room on the board due to spacing constraints, you can put the same information in an assembly drawing.

Ambiguity is the enemy of manufacturers everywhere. Read a bit more on the subject here, or here.

Duane Benson
Help stamp out and eliminate redundancy, and maybe ambiguity, or maybe not

Tell The World...

4mil top viewAnnouncing our "We thank you" customer referral program.

Screaming Circuits always appreciates it when a customer tells someone about us and that second person becomes a customer. We love helping engineers get their projects finished, and the more people that let us help, the better for everyone.

So, in appreciation, if you tell another engineer about us, and they become a customer, read below to see if you'll qualify for our $500.00 new customer referral bonus.

I don't like fine-print, so Here's the deal in big print:

  • First, we know that not everyone can receive personal gifts due to company policy. We have an solution for that. If the referral qualifies, you can choose either a $500.00 credit card gift card, or, a coupon for $750.00 off the cost of your next assembly order of $2,500 or more.
  • You, the referrer, must be a current customer of Screaming Circuits.
  • The new customer can not have been a customer, or registered on our website, as an individual, or company, prior to the referral. Sorry, but it can't be Elliot (or equivalent) in the next cube over.
  • The new customer must place a Screaming Circuits assembly order of at least $2,500.
  • The order from the new customer has to be placed and paid for during the period from November 1, 2015, through December 31, 2015, and it must be delivered by January 31, 2016.
  • If you and the customer qualify, we'll deliver you the gift card or coupon after they have received their qualifying order.
  • If more than one person refers the same new customer, the first person who sent us the referral gets the bonus.
  • There is no limit to the number of referral bonuses, as long as each one qualifies as a new customer and their first order is placed and delivered, during the program period.
  • You're responsible for any taxes due. If you earn more than one cash bonus, we'll need to send you a W-9 for you to fill out and return. You'll have to properly fill out and return the W-9 before we can send the second gift card.
  • And, to the person in the next cube over from me; sorry, but anyone affiliated with Screaming Circuits, Milwaukee Electronics, or any of our partner companies is not eligible. (If you're a customer and refer someone, you're okay. You just aren't eligible if you work for any of us or our partners)
  • Finally, you must be in the USA.
  • Yes. I know, that's a lot of "conditions", buy hey - it's $500.00, so give me a break.

That's a mouthful. If all that fits, all you need to do is send me (dbenson @ screamingcircuits . com) an email with the following information:

  • In the email subject line, put "New customer referral"
  • In the email, put:
    • Your name, company name, and your Screaming Circuits customer number or log-in name.
    • The name and company name of the person you are referring, so we can match them up with their qualifying order.
    • Whether you're interested in the $500.00 gift card, or the $750.00 assembly coupon.
    • Your T-shirt size (optional)

Once you do that, we'll track them and their order. If they qualify, we'll contact you. If for some reason, they don't qualify, we'll let you know rather than leave you hanging.

Duane Benson
For those about to refer, we salute you


How to Make Your Child Interested in STEM

STEM (Science, Technology, Engineering, and Math) careers are getting a lot of press these days. They are important for global competitiveness and the general advancement of human-kind. STEM is also one of the few job markets (especially the “engineering” component) with good salaries and a lot of opportunity. It’s natural to want your kids to head in this direction; so how do you go about doing that?

First, and most important, if your child has no interest in STEM - maybe wants to be an artist or a welder -  shut up, be a parent, and support them. We need artists and welders too. Those aren’t second rate choices. They’re just choices, like an engineering career is a choice. We need kids that will grow up to be happy adults, not puppets. You can introduce STEM, but don’t push it and don’t make them feel bad if they’re not interested. Someone who has passion and support for what they do is more likely to be happy and productive than someone pushed into something they don’t want.

Beyond that, you again need to be a parent. Listen to them carefully and look around to see what they are up against. My daughter started in the FIRST Lego robotics program in the 4th grade. Her teams were about equal proportions of boys and girls. But, by the time she left middle school for high school, she was one of two girls left in the program. Through high school, she was always a tiny minority in her science and technology classes. It’s not just girls that drop out, but it seems to be most noticeable with girls due to the numbers.

The peer and societal pressures have been described many times in many places before. It’s sufficient to say that, in many circles, being a geek is not seen as being socially acceptable; except in the context of a TV sit-com. It’s funny when the “geeks” can throw out one-liners that have been crafted by a team of Badge 700professional writers. Not so much when it’s the kid in the next seat over that struggles to respond to conversations about football or beer brands. Help your child to understand that technology and knowledge are not qualifiers for the “weird club.” Make sure they also understand that labor and grease also are not qualifiers for a different kind of “weird club.”

The recent case (late September, 2015) of the 14 year old boy arrested for bringing his “homebuilt” clock to school is a good case in point. Many people fear wires. In the movies, blue, green and red wires are what you have to choose wisely between to successfully defuse a bomb. In the real life world of a 14 year old kid, with a mind thirsting for knowledge, blue, green, and red wires are signal, ground, and power.

There is quite possibly a lot more to this story than has been published, but maybe not. Later articles talked about the fact that his clock was simply a purchased clock, taken out of it’s plastic case and hacked into a mini-suit case. Deriding him for that is a sure fire way to stifle curiosity. When I was 14, most of my “electronics projects” were of a very similar nature. Many were even less complex.

The first time you open up an electronic gadget is like opening up a grab bag. You don’t know what it is, nor what you can do with it. You see shiny metal, wires, chips, and display. You know that whatever makes it all work is truly amazing, but you have yet to grasp the significance of any of the parts. Over time, you will. Or, you will if you manage to keep the interest up and avoid being branded a delinquent over your quest for knowledge.

If your child takes apart a clock, your obligation, as a parent, is to make sure they don’t electrocute themselves or burn the house down. After that, it’s your mission to encourage. Explain, if you can. If you can’t explain, teach them about research and self-learning. Don’t treat their interest like a disease. Treat it like what it is: the quest of an explorer for knowledge.

Duane Benson
Sit tight, energetic martians

New Super Small BLE Chip

ATBTLC1000 on coins from Atmel siteI tend to get quite excitable when new, smaller, components come along. The smaller, the better.

While, I haven't yet seen it up close and personal, I've seen the announcement and datasheet for a new SoC (System on Chip), with Buetooth SMART BLE 4.1. The whole chip is 2.2 mm X 2.1 mm in a WLCSP (wafer level chip scale) packaged BGA. (Image from the Atmel web site). The part is the Atmel BTLC1000, with BLE and an ARM Cortex M0, running at 26 MHz.

ATBTLC1000 dimensionsIt's got 32 balls, in a staggered pattern. That gives the chip a diagonal ball pitch of 0.3535 mm. That's really small. The staggered pattern isn't too common, but I expect that we'll be seeing more of it as parts continue to push the size envelope down.

Here at Screaming Circuits, We've built a few 0.3 mm pitch devices, and plenty of 0.4 mm pitch parts. I wouldn't anticipate any problems, but if you do get your mitts on one of the things, you should probably take the mitts off (because you'll loose the part) and call us and ask to talk it through with our manufacturing engineers before sending it in.

Duane Benson
There was a demon in the oven. They said whoever solders him would fry. Their pads would bridge, their pc boards would twist and warp. The demon lived at 0.3 mm pitch on the metric scale, 0.0118121 inches SAE. But not at Screaming Circuits. That demon's afraid of us.

Fuzzy Logic in Manufacturing

In the digital world, we're accustomed to everything being driven by the absolute 1 or 0. You can also add in Tri-stated too, but that doesn't really count for computational or conditional logic. Analog allows for degrees of data, but at some point, is still driven by a specific cut off point. To start to understand the concepts of "more correct than incorrect", we need fuzzy logic, which is used in digital computers, but requires a lot more computation than a simple on / off switch.

Our parking lot takes a short-cut to fuzzy logic with cats. We've got a field across the street that has a small population of feral cats. They seem to be happy and healthy enough - although some mystery person does bring some food. I suspect that they'd find enough to eat regardless, but the extra food stacks the deck a bit in their favor.

Corporate cat on car 1024As the temperatures drop in the fall, it's not uncommon for them to hop up onto the warm hood of a recently arrived car, as this one did this morning.

I've heard that in the wild, cats can be quite vicious predators. In fact for the most part, I think that, while if dogs were larger than us, they'd be happy to let us use them as beds, cats larger than us would eat us. But, as long as they aren't eating any of the PC boards or parts that come through here, I don't mind having them around.

Duane Benson
Fuzzy Wuzzy was a bear
But he had no microcontrollers to play with

Continuous Strips of Parts

Not long ago (No Need To Waste Parts), I wrote about the use of tiny cut strips here at Screaming Circuits. That's good information, but only part of the story. (When has anything ever been the whole story???).

IC cut stripThere may be some times when you don't want to buy a reel, full or partial, but still want your parts all in one continuous strip. Everyone wants to use up their odds and ends, but once those are gone, it's easier for you if each part is just in one strip. If you want to save a little money here and can use a longer turn-time, you might want to pick our Short-Run production service. If that's the case, you will need to send in continuous strips. Short-Run requires reels or continuous strip of at least 12" in length.

There are two questions you'll probably ask:

1.    How can I make sure my parts add up to at least 12 inches (305 mm)?

There are two ways to do this. First, if you have some of the parts, measure the length and calculate the number of components per inch. Use that to determine the number of parts you need to get 12 inches.. Make sure to calculate the length based on the quantity you need + 10% (+50%) with 0201 passives).

If you don't have any of the parts already on hand, you can download the datasheet for the component. In the pack, you'll usually be able to 

If the length comes out to less than 12 inches, use the parts per inch to figure out the total you need. If it comes out to 12 inches or more, you're set. Passives commonly come in 2 mm pitch tape or 4 mm pitch tape.

2.    How can I make sure that my supplier sends my parts in continuous strips?

It's not uncommon for DigiKey or Mouser to send 50 parts in 5 different strips of tape. I've even received parts in strips of one. Each part was still in the tape, cut from the reel. They were just cut into strips of one. We can use those in our Full-Proto service, but it's a hassle for you and you can't use them with Short-Run.

Neither distributor has a setting for "continuous strip", however, they do have a place to enter special instructions. Simply state in the special instructions that you need uncut, continuous tape for all parts that come in strips of tape.

Duane Benson
What is the airspeed velocity of an unladen swallow?

Those Danged LEDs again.

I fell into one of my own favorite traps last week: the dreaded LED footprint mess.

I designed a board based on the Microchip PIC32 - it's a ChipKIT Arduino-compatible board - that has a number of RGB LEDs. on it. I used Part number LTST-C19HE1WT, from Lite-On. Their datasheet is easy to find, and they put the footprint information right up front, just the way we like it.

Almost all is well, but I somehow missed taking my own advice, and I didn't double check the footprint.The footprint I used is more or less 180 degrees off from this one. The common Anode is still on pin 4, but the numbering is different. It's got pin one in the same place, then pin two is in the lower left. Pin 3 is on the same place, and pin 4 is on the upper right. That's the conventional pin numbering order.

Fortunately, the fix won't require any mod wires. If I rotate the LEDs 180 degrees, the anode will be in the right spot. All I'll need to do is adjust my software for the correct R, G, and B pin locations.

Duane Benson
I'm dizzy with rotation

PCB West - September 16, 2015

Come join us!

If you're going to be in Santa Clara, California, on September 16th, drop in to the Convention Center. Screaming Circuits will be there, along with our PCB fabrication partner, Sunstone Circuits. We'll be in booth 510, and they'll be in 508.

While you're there, ask us or Sunstone about a special offer you can get by using both of our services.

But wait! There's more! I'll be speaking on best practices at 4:00, on the 16th. Look for session 38: PCB Design: Best Practices for More Reliable Manufacturing. in the conference program guide.

Here's a handy show floor map:

PCBWest 2015 floor map

Duane Benson
Do you know the way to San Jose?
Then, turn left and go Northeast
'cause we'll be in Santa Clara