How do professional engineers prototype using compact surface mount devices?

Based on the recommendation of a few people here I bought a STMicro STM32F4DISCOVERY board a while ago. Last week, ST had Digikey send me an email offering 6 "complimentary Op Amp and Comparator Kits" based on my interest in their development board. They are backordered on some of these kits (I ordered the 4 that I have an idea what they are), but I got the comparator kit today which is a 3x5 sample of the following parts: TS881ICT,TS331ICT, LMV331ICT. These are tiny parts! So this reminds me to ask a question that I have wondered about so far: How do professional engineers prototype using compact surface mount devices? Obviously if you have a pick-and-place machine and a PCB it's no problem, but you are not going to set that up a prototype. I assume engineers do one-offs by hand somehow, but obviously not using a breadboard. How do they do this? Do this just possess world-class soldering abilities and use dead-bug construction? Or is there some sort of way to replace the PCB but not with a breadboard? Is dead-bug construction the norm, or is there a more reasonable way? Or do professional engineers not need to prototype and just bang out their boards knowing they will work fine first time around? XD

If anyone else wants to try to get in on this sample:

https://ordering.digikey.com/promotions/tradeshow.aspx?id=16

  1. Practice world-class soldering abilities using a fine tip, fine solder, and magnification

  2. Use manual-assist pick-and-place "machines" -- basically just a holder for your arm and linkage to allow your arm to pick up and place parts with relative accuracy. Not nearly as expensive as the fully automated pick-and-place machines.

  3. Send out for assembly at places like Advanced Assembly (expensive!)

  4. Use soldering-aid modules like the ones from Schmartboard

-- The QuadRAM shield: add 512 kilobytes of external RAM to your Arduino Mega/Mega2560

How do professional engineers prototype using compact surface mount devices?

I was never a professional engineer in production but from what I read in many trade magazines over the years is that more and more 'prototyping' is done in PC simulators, spice analysis, etc. I know that using circuit simulators is big part of EE college programs and has been for sometime. So maybe they just skip over the practice of a 'pure' prototype version and skip to a pre-production version using an actual SMD PCB and evaluate from there?

I'm sure there are pros here that can share their first hand experience at what 'prototyping practices are now used in industry.

Lefty

i make all my designs using SMD, i prefer them because of how compact the result can be. but i test everything with through mount components. i haven't found a situation where the part i need is not available in both form factors (though i'm sure there are many examples)

RuggedCircuits: 1. Practice world-class soldering abilities using a fine tip, fine solder, and magnification

Can anyone recommend the a fine tip for Hakko FX-888 that would be correct for this? I am still clueless what to mount it TO except to use dead bug construction and point-to-point wiring. Either that or make and wait on a custom PCB for a "prototype" which doesn't seem acceptable.

NeX: i make all my designs using SMD, i prefer them because of how compact the result can be. but i test everything with through mount components. i haven't found a situation where the part i need is not available in both form factors (though i'm sure there are many examples)

Well, sure for opamps and such, but try getting a high speed ADC or a high pin count microcontroller as a through-hole devices. I have seen even LED PWM controllers (the 24 channel ones from TI for example) that are surface mount only. There are no 100 pin through hole devices out there and many, many 100 pin devices out there now - all surface mount.

but you are not going to set that up a prototype.

Well yes professional engineers do, with some chips like BGAs it is the only way, I know I have done it. You might only make 10 and they are horrendously expensive but that is what they do.

As to a DIYer with a small budget you can get adapters, small PCBs with a footprint for the chip bringing it out to wider spacing like:- http://www.ebay.co.uk/itm/10pcs-x-SSOP28-DIP28-0-65mm-pitch-adapter-transfer-board-/180908917879

Wait on a custom PCB for a prototype. It is worth it.

BatchPCB, OSHPark, Seeedstudio, etc. are all very inexpensive if you're willing to wait. 5-day specials from Sierra or Advanced Circuits if you're not.

Personally I like chisel tips, and would start with the T18-C1, T18-C2, and T18-C3 tips and see which one makes you the most comfortable.

-- The Ruggeduino: compatible with Arduino UNO, 24V operation, all I/O's fused and protected

There as many methods as there are engineers.

Most will begin with evaluation kits, if they are available, for parts they are not familiar with. They can wire them into a pre-prototypes using jumpers and solderless breadboards to test basic functionality (proof of concept). If evaluation kits are not available from the part manufacturer, they may do up some DIP modules and get them made up either in their own manufacturing faculties or farm them out to a service shop, then build proof of concept prototypes with them. Most complex projects will go through a beta prototype stage too, where they get full blown boards made in small quantities for testing and evaluation. A lot of service shops offer this service at a surprisingly affordable rate, but most bigger manufacturers have their own facilities. Small, less complicated projects, where they are taking a modular approach to their design often go directly to small scale production right from the proof of concept stage. What I mean by a modular approach to design is using predefined and tested modules, like power supplies, control circuits, displays, input devices, etc. to build up designs from. Using a repeatable process based on proven design modules can often drastically reduce the amount of effort that goes into a new product even if it does use a new SMT component.

If you check ebay, you can get a sheet of small part SMD adapters to DIP spaced holes for prototyping. $20, get a whole mess of little cards on a sheet tht at snap apart. Last one I got was from a place in Thailand I think. Had pads for 3,4,6,8,10,12, different pinout on each side, use one or the other.

I recently wanted to prototype a boost converter and the best package for hand-soldering that was available was a six-lead SOT. So I had three small boards made at OSH Park for the princely sum of $6. Worked out really well. I designed the prototype boards to plug into the power rails on a solderless breadboard, so they will continue to be useful as breadboard power supplies.

(I'm an engineer but may not qualify for the professional part ;))

How do professional engineers prototype using compact surface mount devices? Obviously if you have a pick-and-place machine and a PCB it's no problem, but you are not going to set that up a prototype.

That's exactly what we do! I work for a small electronics manufacturer. All (almost all) of our PCB assembly is done by an outside contractor. We don't do "breadboards". We get a small quantity of bare PC boards fabraicated and send out a "kit" (usually 5 boards) to the assembly house where they have the pick-and-place and all of the other equipment to do it "right".

It's expensive and it's all part of the development cost/budget. But in reality, it's probably not much more expensive than having an engineer or technician spend a week or two building a breadboard. And, it's usually just not practical to build a breadboard.

If there are a few small changes or corrections, we can usually do "cuts & jumpers" in-house. (An assembler does it, not the engineer.)

So far, I've been able to avoid surface mount on my home projects. In fact, lately I've been building the permanent project on plug-in breadboards (whenever practical) to mimimize soldering at home.

RuggedCircuits: 2. Use manual-assist pick-and-place "machines" -- basically just a holder for your arm and linkage to allow your arm to pick up and place parts with relative accuracy. Not nearly as expensive as the fully automated pick-and-place machines.

Like this: http://www.abacom-tech.com/%2FManual-SMT-Pick-and-Place-Machine-ezPick-P93496.aspx ? What other solutions are there?

They may have technicians to solder them: I know people who can hand repair bga chips. I can solder lqfp44 chips with fairly good success rate, with just an iron. With a hot air gun plus flux, smd isn't bad: 1206 is completely doable for example.

Or they have a small reflow oven.

Either go straight to pcb, or use SMD adapter boards. As well as the ebay suppler that Mike mentioned, you can get inexpensive SMD adapters from SparkFun, Futurelec and breadboard-adapters.com, and expensive ones by Roth Electronic from Farnell.

Soldering SMD chips on adapter boards is quite easy using a a flux pen, solder paste and a hotplate, followed by solder wick if needed to remove excess solder.

Here's one example, looks like a nice collection http://www.ebay.com/itm/SMD-CONVERTER-ADAPTER-PCB-BOARD-SOIC-SOT-MSOP-TO-X-7-/120964399509?pt=LH_DefaultDomain_0&hash=item1c2a0a4195

http://www.ebay.com/itm/Universal-SMD-PCB-Board-TSSOP-to-DIP-Adapters-/320777381760?pt=LH_DefaultDomain_0&hash=item4aafd26780

This is the one I got last time http://www.ebay.com/itm/SMD-CONVERTER-ADAPTER-PCB-SOT-TO-MSOP-SIP-DIP-14-/270832318388?pt=LH_DefaultDomain_0&hash=item3f0edd37b4

Just search for "smd adapter" and scroll thru.

I did pretty much a combination of all the above because I started fab in thru hole and went to 1206, 0805 and the last board I did was smaller for the thru hole we hired a temp assembler it it was more than the first article and that one I did myself... until the 805's. All of the PCB houses I've dealt with have been willing to run a panel and "Give" you one, You get the rest when you pay... If you make a mistake and cause them to generate a new plot you have bought your final working order + 1 unfinished panel @ regular price. Most are fussy about having to recheck for manufacturability or you just "Buy a Lot" of PCB's. Win loose or draw it adds perhaps $50.00 to the fab cost so most of the PCB houses I dealt with did it that way. They Really Never loose anyway.

Bob