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How do you source new components?

One thing that I have been thinking about when you design new hardware, is how do you find where to buy new components?
At the regular places to buy electronic components, they usually don't have the best components for sale. And many components have ridiculous pricing.
Components I am thinking about is things like displays and memory.
How do you work to find the right parts?
How do you find the components in the first place?
And where do you buy?
And at what type of company do you have to work at, to be able to buy?

I use Mouser, Digikey,

I use Mouser, Digikey, Futurlec and Taydaelectronics.  The cost of parts goes down if you buy hundreds and even farther down if you buy thousands.  Surface mount parts are even cheaper.  There are other companies that sell parts by bundles.  If you were to give someone steady business or buy more than 10 or 20 thousand parts, they have special pricing and you can negotiate your own price.

How do you find components?  You get catalogs or you go overseas.  Going overseas doesn't always solve the problem because some of these companies are international and they won't sell you an Arduino any cheaper from China than you can get it from the United States or elsewhere.  I bought a development board from an overseas seller on ebay and stamped on the bottom was a sticker with the maker's email address.  I emailed them and I couldn't get the product any cheaper even though I offered to buy straight from them. 
Cash is king.  If you have cash and can get a datasheet, you won't have a problem.  The problem is if you call a company's engineering department, they won't usually talk to you unless you are a business because it costs money.
If you buy from a reseller, they have to make their profit somehow.  Rent and labor is what drives the price up.  If you were to buy a  part from Radio Shack, the price is controlled by mall rent and labor with a few other factors in there.  If you were to buy resistors or capacitors by the reel, you don't have to pay someone to cut the part or count the part so it will be cheaper.  You can buy parts by the reel and get a better price.  Arduino sites seem to be cheaper than others but some of them are selling an LED for .25 cents because they have to make their profit and you can probably get one for .04 cents by buying them by the hundreds through a company like Digikey, Mouser, Futurlec or Taydaelectronics.
The other issue is that products are often made by using discreet components.  Too often people are more than willing to throw a microcontroller in every project and when I get the bill of materials, I can spend over $100 for a clock that I can buy from Wallmart for $10-$30.
One of my friends uses ebay.  I just bought a pack of 100 LED mounts for less than $3.00.  A reseller is going to buy that and sell you a couple for three dollars.
One of my friends has a friend that owns an LED factory.  It costs him two cents to make 100 LEDs and you can get a pack of 100 LEDs for $3 or $4 on ebay. 
If you did have a company then maybe a salesman might visit you and give you special pricing but a lot of times it is just a game and other times it isn't.  These start up companies will charge you double because of unforeseen costs.  My employer tells his customer service people to add on at least 5% or it isn't worth doing business with people.

We have a client who didn't want to pay 5%.  What is 5% of a million dollars?  It is $50,000.  Can you pay a salesperson on that?  Some salespeople and companies will say "no".

One thing I used to be sort

One thing I used to be sort of known for and that I still do is I start with a price sheet in front of me, or at least a good knowledge of parts costs and design into what I can afford.  I had a friend ask my advice where it seemed that one of his employees was targeting an FPGA of a couple of hundred dollars, because it's the part/family that the vendor talked about.  By looking at the price costs on Mouser and Digikey I worked my way up into a CycloneII or III part that would do the job for about $11 instead.
Single piece costs are comparably expensive, remember that there are price breaks at 50, 100, 250 500 and 1000 pieces when pricing things out.  It's all about what can you afford to build by way of quantity.
A couple of times I have designed things for people that would give me a to-build cost of $50 in 100,000 qty, and then realize that they couldn't write a check for $5 million.
I assume that as anyone asking the question about parts cost is realistically looking for parts between 1-99 qty and they are a tad expensive, whatever your building would be priced on niche and uniqueness not mass market competitive cost.

Well that's good advice.

Well that's good advice.

Usually I always sort the lists I go though, by lowest price first. Then the next thing that I use to do after that, is to take the most expensive parts and find another suppler for these components that will give me a better price. It's worth looking for that. Not for all components, but for the ones where you could cut most bucks.

Another thing I use to do, is find MCU's for example, that have all the features that I need built inside. One thing to look for is built in schmitt triggers, and pull ups on the I/O pins. And if it is a flash based MCU, it could be possible to save data at run time in that memory. And maybe it's sometimes only a matter of changing some characters to save enough memory to downgrade to a less expansive version of the chip. That’s the power of C and rapid development. And please don't use 8bit parts. Today a 32 bit chip cost less and consume less power and has better tools, free tools, and have much higher performance. Take a look at Cortex M0+ for example. And if you need low power consumption, look for Energy Micro.

Another thing is to closely look at what type of extra components different chip uses, and to look for peripherals that can he built in to some chips. And I think it's very important to save board area, it is often the most expansive part in the whole construction. And when you make the PCB, you could save a lot of money be finding smart ways to to route and place components. If you go for high EMC you will most often also make good low cost board's, as it forces you to make short and smart signal paths.

There is loads of really stupid components out there. In fact the majority of components are stupid, and that's about 90% or more of all components. And it's often that you see components that would have been long gone forgotten, if people didn't look at other peoples bad designs.

And one more thing, look for LDO regulators, there is some that are incredibly good, small and low-cost, that don't need external parts. And ceramic capacitors will often make the device preform better and it also saves board space and money. Unfortunately people often chose capacitors that are a couple of hundred times worse, and cost a lot more, than a component that can be up to magnitudes better and cost less.

And one thing can be to let Asian companies source the components for you, the “rumor” is that the price is often cut in half.

There is other things to think about also, but that's another chapter. Most people actually don't know what they are doing, only because that person look at another person. So if you are uncertain, don't copy. If you are uncertain, then probably all those that came before you, was probable also uncertain, and copied the design from some that was totally clueless and didn't know what they were doing.
I think it's important to trust your own gut, if you are uncertain stop and think again and test, there is nothing so stupid as superstition and to think that you already know it all :-)

Arduino vs Pic

The Arduino is basically an AVR chip on a PCB and they charge you $30 for it when you can buy a Pic for $2. If you try to outfit a classroom it is basically $900 vs $60. If you have a Pikit 2 add another $60 and $150 for breadboards. I would get kicked off of Arduono sites for saying this because I'm touching someone's money in this even though there isn't much of a margin. The Arduino works on C and a Pic can be programmed in Assembly or Swordfish basic which is free. There are a lot of nice development boards out there but they drive up the cost with their tools and add ons.

Well these 8 bit devices are

Well these 8 bit devices are popular, but it's bad influence. Why learn something that no one with a sober mind would use any more? And don't get me wrong, there can be times that 8 bit MCU's are ok, and it is if you want to have it in a sot-23, or you neither need the speed or memory, and you simply cant afford anything that cost $1 or more.

You can get a 32-bit bit MCU much higher speeds, much more program memory and much more ram, for much less cost. Try to get a PIC that runs at 200Mhz that cost less than $1. That is what you have to compare with, as a 32bit ARM at 50MHz for $1 uses 4 times less Hz per clock cycle. If you need something that costs less than $1, or something really Small as a sot-32, then I can understand why you want to use a PIC. But it's bad practice to use 8bit chips as your primary target. It's backwards movements, like the crayfish swimming. Keeping the society incapable of future progress.

Lets face reality. The only reason that people use 8bit chips, is that they are used to program 8bit chips. But why would you give this bag of heritage to someone new? I think the only reason is that the teaches skills are insufficient to learn others, what they could expect to be given by respect of their time. And I think it's disrespectful to teach something that belongs to the 80s, to people that live 30 years later.

What are the reason to teach people to use old stuff? If a teacher don't have the skills to keep up with the present in respect to those who he teaches, why is he a teacher? For what persons sake is that teacher there to nature his own passion for nostalgia? or is he really there to teach others something that could be worthwhile even in the future? Why teach them something that is futile, and that can't be used on the open market? Create shrimps or studs? Well the only person to chose, is the teacher behind the mirror. We need to make a bold move to something better, the humanity desperately need fine persons like that. We have to start to think twice, before we start acting like those creepy fossils from the past, deep down dwelling in the mud. Is it the humanities calling, to be like shimpy shrimps? Was it a mistake to climb down from the trees? Is it time to start to eat more bananas? Well that depends on our own calls for the future!

Microchip does have a 32 bit

Microchip does have a 32 bit 80 MHZ chip.  The Pic 32 USB Starter Kit II board was only $55.
The Pic 32 I/O Expansion Board was $72. The rest of it is where it gets outrageous because the C Compiler was $895 and the MPLAB REAL ICE PROBE KIT was around $500. I could see spending money on the board but the C compiler and MPLab Real Ice Probe Kit will never happen.
If you are an Engineer, have the money and have to be competitive then you are right.  If you are me who bought an Amiga, wanted to start a company and end up going broke because the Amiga technology was more expensive than the Commodore 64 audience could afford then it is a "no".  The problem with STEM in many schools is they don't always have the money for all these electronic toys to learn on.
My son may have a teacher in school in third grade that is into electronics and he makes sounds with resistors and transistors because at that age, it is the most kids can handle.  There is a company called "Little Bits" wants to stay analog as long as possible and I believe it is because not all learning is digital.  Radio is where a lot of people got their start in electronics and there were some vacuum tubes that were better amplifiers than some of this modern stuff.   It is also hard to convince a parent to spend $30 on an Arduino when you can spend $4.30 on an MSP430 from Texas Instruments which is less the price of a Happy Meal.  My stepbrother has been programming computers for many more years than me and I tried to get them interested in doing some of the kits with me and his reason is that while he is interested, he wants to see me do it first.  The reason he doesn't want to do it is that electronics is hard, it takes people a long time and it is very expensive.
When I got a Commodore 64, I learned Basic.  I learned Pascal and so forth.  Basic is basically a bootloader.  A bootloader makes things easier.  Does a bootloader now translate into skills today?  No.  The Arduino succeeds because people connect a few pins, cut and paste code into a chip and voila; the Arduino translates into sudden success for art students who have no experience and they think they are programmers or have arrived when reality is that some of them have no understanding of basic electronics.  Most beginners don't know that if you don't put a resistor next to an LED that you will forever ruin your Arduino.  There are low cost versions of the Arduino and teachers use an FTDI cable seperately so that if a student blows a cable, it isn't a total loss because they have kept the components seperate.  Can the Arduino users then take their skills and program a different chip?  Some can and some can't because they have to read the manual.  If you don't have a basic understanding then I doubt you can go from one platform to another platform because it involves learning.  But the Arduino crowd will have support because it is easy whereas you won't find beginner articles for the Pic 32 because the hobby forums haven't been able to dumb it down for users to learn.
On the other hand, if someone was to learn assembly, they would have an idea about processors but Assembly might be considered a dead skill set today but I would have skills.  Programmers have been replaced by powerful tools.  The problem with that is that the industry is throwing information at people without them always learning.
So if you were going to teach electronics in a school, you would pretty much forget chips that ran faster than 50 MHZ in dip form because breadboards can't handle too much speed.  You would have to get a development board or module which drives up the price otherwise they would have to get a small enough soldering iron to do surface mount soldering and I bought a decent soldering station with a 1/64th inch tip from Elenco for under $40 while others would go with Hakko or possibly Weller.  Already you have the price going up which parents are not going to contribute to unless they are willing and are convinced there is some benefit.
I've been on the Parallax forums and they try to disguise the fact that their Propeller Chip is only 12 MHZ by saying it runs at 120 MIPS.  But they have a following and a lot of them are devoted to this chip and their propaganda is that their chip makes everything possible and that it can do video but Arduino can't do video very well.  They also have a very good forum for doing teaching whereas the AVR Freaks Forum is closed to new registrations and the Arduino's official website is not suitable for school age children in the eyes of parents.  Parallax's propaganda is their chip can do many things at once and that other chips can't.  There are users that come on the forums wanting to do this and wanting to do that and the more experienced users are like college professors who tell the new users that they (the new users) don't even know what is involved.
The other argument is "results".  I know people who are still using the 6502 and other 8 bit chips.  They believe the older ways are better and they are still creating projects.  One of my friends makes projects on 8 bit Microchip Pics and he has been on Instructables and Hackaday.
I think that an eight bit chip is a good place to start.  If you ruin a $2 chip then it isn't the end of the world.  I just don't think it is realistic to find beginner tutorials for a Pic 32 and those teaching electronics in engineering schools use the Arduino as a starting point.  These electronic hobby sites aren't going to throw a Beaglebone at beginners because the datasheet for the OMAP chip is like 3500 pages long which is a little intimidating.

Maybe I'm a bit fuzzy. When I

Maybe I'm a bit fuzzy. When I speak about 32bit, I talk about ARM.
Forget microchip. That company has newer done any CPU design. They didn't do the original PIC design, and haven’t done the PIC 32 either. And now days it's almost futile to try to invest money to make something worse, when you could license an ARM core, and get something better. That’s why they newer will make any own cpu design, they don't have the knowledge to do it right.

If your budget is $1 or more. Then 8bit chips is more expensive than 32 bit chips. Let say your budget is $1. Then you will get more program memory and more working memory if you use a 32 bit ARM chip. Lets face facts, take a look at LPC1111, (cortex-M0) now tell me what 8bit chip has more program memory, and working memory, or speed for that kind of money? So the price on chips could not be the issue.

And as ARM is getting more any more generic, the prices is running down to zero faster and faster for every day.

Maybe it's possible to hide from this reality today, but eventually the future will catch up on everyone.

And the tools for programing C is free for the ARM platform. That could possibly not be the problem.

And you don't have to run them at 50Mhz, you could run them on at any speed you like down to 0 Hz. So to high clock rate can't be the problem.

It's only a question of time, before the 32 bit chips will take over the market. The reasons to use an 8 bit chip is running out. It's simply a question of time.

If people isn't smart enough to relearn and use new technology, then there is an even bigger reason to stop teaching people to use 8 bit chips right away.










Sourcing cheap parts on TaoBao, China’s eBay

I have a Cortex M3 development board but they aren't cheap.  You're looking at spending $50.  The Jtag to USB connector by Olimex was $50.  And I think there is a ST Link which I haven't bought but I'm sure it isn't cheap.  I'm figuring these chips aren't in dip form so you are looking at either manufacturing a development board or buying the F4 from Mouser or Digikey for $15.  The manual on Amazon is around $40 for the chip so this looks like an elective High School course and not something you can teach overnight to your students unless you are really good.  The schools would have to install the IDE for the students because it could be a nightmare for some of them.
As far as sourcing foreign parts, there is China's version of Ebay but you need to find a broker and watch out for substitutions (check out the comments).


These new 32 bit chips are much more powerful, but aren’t exactly hobbyist friendly. Most of the ARM chips we’ve found are stuffed into very fine pitch QFN or QFP packages that require a reflow oven to solder to a board. In fact, we can only find one through-hole Cortex M0 chip that is suited for breadboard development. This doesn’t make it easy to whip up a circuit in a few hours, so builders needing a very powerful microcontroller will be more dependent on dev boards.
I haven't had time to build a reflow oven.  It seems kind of expensive to go out and buy a toaster oven and also a controller board to turn it into a reflow oven.  This is part of the reason why I don't think ARM is ready for the hobby market.  When you are married, busy and with children, this adds an extra level for users to overcome and some can and some can't.  When you are learning and you can't overcome the next step, your wife can say to you, "Why don't you give up?  You haven't been able to do what you've set out to do.  You haven't been able to learn it."  We're on a budget and most Americans don't have savings accounts so when you save up for that development board, you pretty much have to wait for your tax return money to go buy the next step.  I didn't know what I was getting into when I got involved in electronics; I found a thousand rabbit trails to go down because I didn't know what was involved.  The reason one of my relatives doesn't want to get involved in electronics is because it is expensive, it involves a lot of time and it is very difficult.  A lot of these beginner kits are geared towards those who already know what they are doing and I even bought a kit caleld "getting started" and I called the company who makes it and they told me I should have started with a kit before that one.  I met a retired contractor involved in electronics and I wanted to know how to do such and such and he wouldn't teach me because he said, "you don't know anything".

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