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I've just finished designing my first PCB, and I'm about to send out a batch of emails for quotes from manufacturing/assembly shops. My design is super simple: the only components are 7 identical SMD resistors, a 5v voltage regulator, a decoupling capacitor, an ATMEGA328P-PU and 16 pads for off-board wires. I'm looking to do an initial run of 50 boards, with the possibility of ordering more later. I'd also like to receive a prototype to verify that everything works properly before putting in a purchase order for 50 more boards.

I'm very new at this, and Google provides an overwhelming number of shops to choose from. This post seems to have some good advice for ensuring quality, however it seems that such a small, simple board wouldn't fall prey to many quality issues.

Beyond the advice in the above thread, does anybody have any recommendations for what I should ask in the email? And further, if anybody has any suggestions for particular shops to reach out to, I'm all ears. Less expensive is better, but not at the risk of receiving defective boards.

Edit: Also, would you anticipate that it would be dramatically less expensive to just solder the boards myself? And if it's worth it to have the PCBs assembled, is it more or less expensive to let the shop source the parts themselves? I'm not sure if they would get a better deal on the parts, or if they would be overcharging me for them.

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    \$\begingroup\$ You can get really fast quotes from OSH park. They are good for simple boards. \$\endgroup\$ – R.Joshi Jul 20 '17 at 13:36
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    \$\begingroup\$ "... the only components are 7 identical SMD resistors, a 5v voltage regulator, an ATMEGA328P-PU and 16 pads ..." - Soooooo, no decoupling caps? \$\endgroup\$ – marcelm Jul 20 '17 at 14:11
  • \$\begingroup\$ @marcelm Good catch! I have a 0.1 μF decoupling cap. I'll edit my post. \$\endgroup\$ – Gabe S. Jul 20 '17 at 14:21
  • \$\begingroup\$ If you have a 5V regulator then it should also have 2 caps (not technically always necessary but highly recommended). L7805 Datahseet, check out section 6 (Page 23) \$\endgroup\$ – Doodle Jul 20 '17 at 14:24
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    \$\begingroup\$ For microcontrollers and regulators the bypass capacitors can be very important. I would say have a place for them but don't populate, if board fails then populate. \$\endgroup\$ – R.Joshi Jul 20 '17 at 14:41
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Depending on how time-critical this is, go to China. There are loads of Chinese places that will do this for a much better price than anywhere else. The only drawback is it takes more time. I have personally used iTead and fusion and have had no problems whatsoever with their finishing. The only issue I had was if the silk screen is too small, it gets a bit illegible, but that has only ever happened when doing a space critical PCB with 0402 components.

It is up to you to do the math for if it is worth doing the soldering yourself or not. For something that sounds quite simple with few components, and only 50, it may be worth doing it yourself, and if you do larger batches in the future, then look at getting somewhere else to do it for you.

As for what you should ask them, ask how much it is for different size batches (some do 'price per PCB' reductions every 50, some every 100 etc) and ask them what quality checks they do, and what process controls they have in place to avoid problems. Ask minimum drill size, for vias, trace to trace width etc. You will have to ask them how much it is to source components, they should be able to give you a quote on that, and then you can check yourself to see if you can get it cheaper.

It is up to you whether you want to go local for speed of delivery, or afar if you can wait, but do expect quite a price difference if you decide to keep it local!

EDIT Both of the places I recommended also do very cheap prototyping, usually in small batches (10) where you can verify your design. For prototyping, it is most likely worth assembling yourself so you can do anything you want to do during assembly to help testing.

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  • \$\begingroup\$ Thank you for the well thought-out and thorough response! I've done some preliminary price-shopping on websites that offer "automated" quotes, and ordering boards from China seems to be the way to go. I would be willing to order locally, but it doesn't seem like many shops in the U.S. are competitive within a 10-15% margin for my needs. I realize that the answers to some of my questions are variable and personal, so thanks for your input! \$\endgroup\$ – Gabe S. Jul 20 '17 at 13:45
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    \$\begingroup\$ No problem, glad you found it helpful. It is unfortunate that most local places cannot compete price-wise, however, if you find you ll be nee batches and more regularly, you can revisit the idea of getting this done more locally. \$\endgroup\$ – MCG Jul 20 '17 at 13:47
  • \$\begingroup\$ oshpark.com is another really good cheap PCB manufacturer. I used them for the first time recently and I'm pretty impressed with what they did. Quality comparable to itead.cc with a bit of a quicker lead time (as you're from the US oshpark.com can be less than 2 weeks as that's where they're based) \$\endgroup\$ – Doodle Jul 20 '17 at 13:56
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You can get really fast quotes from OSH park I believe they are an American company which should make things simpler for you. They are good for simple boards. Worth a try and you can also get a small initial batch of 3 to test out for fairly reasonable cost.

I would say to source the parts yourself if you know your requirements and are confident enough. PCB companie will most likely charge a premium for the service.

The type of questions to ask:

  1. Their minimum via size, minimum track to track clearance etc. most PCB manufacturing firms have this sort of information on their website (design rules).
  2. Ask them directly if you can do anything to reduce manufacturing cost, one PCB manufacturer helped me with this before.

If the PCB is fairly simple I would assemble my self for cost reasons if you are confident enough.

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  • \$\begingroup\$ Thanks for your input! It seems a lot of people are echoing the OSHPark sentiment, so I'll certainly get a quote from them. I'm definitely going to ask for bare boards for the prototype, so I'll hopefully be able to judge whether or not I want to spend the time to hand solder 50 or more. Asking them how to minimize cost is a great idea; I had considered doing that, and it's great to know that it's professionally acceptable! \$\endgroup\$ – Gabe S. Jul 20 '17 at 14:00
  • \$\begingroup\$ Remember you are their customer and you can take your business elsewhere. Re OSH Park the quote is an automated process so it should not take long at all. It is a community based thing so they group lots of boards together for manufacture. Their turn around is very quick. \$\endgroup\$ – R.Joshi Jul 20 '17 at 14:45
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I have recently been in same situation. I reached out to my network and some frequent name came back: PCBway, seedstudio, eurocircuits and dirty PCB.

Now the initial cost of PCBA is quite high, so what i did for prototyping was buying PCBs and stencils at PCBway. Then I did the soldering and assembly my self. Now I'm moving to the next step which is production of a batch and I'm probably gonna go with either PCBway or seedstudio. Sparkfun has a great tutorial on this https://www.youtube.com/watch?v=WDIqtGMROjM

Regarding the turnkey solution. If you have a large amount of chips and buy the directly from the manufacture you often have a personal contact person which can help you a lot. In my opinion if I had low volume - just get the full turnkey solution. If the volume grows I would supply the key components such as MCU's my self and let them deal with resistors, capacitors etc...

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  • \$\begingroup\$ I'll definitely check that tutorial out; that's an option that I hadn't considered at this point. I noticed that a lot of the Chinese turnkey shops offered passive components for free, so really I would just be paying for the Atmega328s and possibly the voltage regulators. If their markup isn't too bad, I wouldn't mind paying a little extra for a small run. Thanks for your input! \$\endgroup\$ – Gabe S. Jul 20 '17 at 13:51
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If I'm prototyping, I usually use someone like itead.cc or oshpark.com. I see you're from the US so i recommend oshpark as they are based in the US and have pretty quick delivery.

I order a couple of bare boards (depends on size, but you can get 3 for ~$15 usually including shipping) and hand solder them myself just to check that my layout is correct and that I've not made any silly mistakes.

When it comes to emailing the manufacturer. You need to make sure you have a BOM ready for them to and to send it along with your gerber files. When making a BOM i usually list all the important parts with RS or Farnell numbers to indicate that I want that specific part. As for unimportant things like SMD resistors and caps I just list the value and size I want and include a couple of lines at the bottom of my BOM:

  1. SM Components: Resistors to be TE Connectivity CRG series. Ceramic Capacitors to be KEMET X7R, or equivalent RoHS compliant parts, unless otherwise stated.
  2. For generic IC parts any equivalent RoHS compliant part may be used.

The reason I do this is that PCB manufacturers typically do what you tell them, if I list an RS or Farnell part number, they'll just buy that at whatever price it is. Leaving it open to them means they'll try to obtain the equivalent part from their own suppliers at a much cheaper price usually.

Also when asking for your quote ask for the 'bare board' price as well as the assembled price. You can then decide for yourself if it's worth soldering them yourself or not.

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  • \$\begingroup\$ Yeah, I figured I would order the prototypes as bare boards and then determine for myself whether or not it would be worth my time to solder 50+ boards by hand. Also, the BOM advice is extremely valuable, thanks! It made me realize that I needed to research how to properly format a professional BOM (I actually think Eagle has a built in BOM function). \$\endgroup\$ – Gabe S. Jul 20 '17 at 14:02
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    \$\begingroup\$ I tend to just use excel personally! \$\endgroup\$ – MCG Jul 20 '17 at 14:08

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