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12 votes
10 answers
4k views

Is it practical for firmware to be uniquely identified in production

Are there systems available in large scale manufacturing that allow a unique serial number to be programmed into the firmware or some free memory space for each PCB that comes through? I've found ...
Lukeyb's user avatar
  • 223
11 votes
3 answers
3k views

Can I assume counterfeit components?

I recently received a run of 10 PCBs from a manufacturer in China, and am worried they have begun to cut corners and source counterfeit parts. Here is why: I had them do full turnkey production (PCB ...
Jim's user avatar
  • 1,657
10 votes
3 answers
2k views

What are some reasons for hand painted dots on chips?

I've seen lots of products with hand painted dots or markings on chips, what do they often mean? Obviously I understand everybody has their own reasons but could it be an industry common practice for ...
crossroad's user avatar
  • 1,430
9 votes
3 answers
2k views

Anyone know the premise of this PCB assembly note?

The assembly note states: Bake bare PCBs in a clean and well ventilated oven prior to assembly at 125*C for 24 hours. Why is this necessary?
klamb's user avatar
  • 312
6 votes
2 answers
666 views

Specifying BOM substitutions / alternatives with Contract Manufacturer (CM)

I fear this question may be opinion based but I think it has some value to the general community - because this falls into the end of the design phase. When working with a CM, they may have better ...
efox29's user avatar
  • 12k
6 votes
1 answer
848 views

How do PCB fabrication houses make PCBs?

I know the different ways of making PCBs at home, but I can't seem to find a lot of information on how board houses professionally make their PCBs. Is this how they do it?: http://www.youtube.com/...
Nate's user avatar
  • 4,546
5 votes
3 answers
2k views

Question on "Parts should be used within 5 days after opening." statement on component shipping package

I've been given the task of verifying a batch of ICs from a chinese broker, to see that the chips the company has bought are what the broker claims they are. The package we've received looks like this,...
Lars Petersson's user avatar
5 votes
3 answers
1k views

Good way to affordably manufacture low-quantity PCB?

I am thinking about making an open-source development board for a specific field in power conversion. If there is interest from local universities, I will manufacture a few hundreds of these boards. ...
user02222022's user avatar
  • 1,656
4 votes
1 answer
1k views

From what pitch should I consider ENIG finish

My design (4-layer, FR4, 1.6mm) has a couple of ICs with 0.5mm pitch pads and some LEDs with 0.4mm pitch pads, very small LEDs. Should I consider ENIG (more expensive) or will HASL do the job? I read ...
Gilad's user avatar
  • 2,127
4 votes
2 answers
1k views

Placing through hole and SMT on the same side

I have a design with huge push buttons (with 6 TH holes.) There's a few of them so they do take up quite a bit of space mechanically from the top. I was thinking of placing the majority of the SMT ...
Hasman404's user avatar
  • 757
2 votes
2 answers
216 views

Connectors in high volume manufacturing?

How are connectors such as USB handled in high volume manufacture? Would the panelized board leave room to place these connectors or would the panel be cut apart and the connectors added later. Is ...
vini_i's user avatar
  • 7,137
1 vote
2 answers
177 views

Nomenclature for tested PCB assemblies

I want to unambiguously refer to an assembled PCB that has been tested. I am familiar with the terms: PCB - unpopulated printed circuit board PCBA - PCB assembly, a PCB with all the parts fitted and ...
stefandz's user avatar
  • 4,172
1 vote
1 answer
144 views

Manage Software Installs of your Semi Mass Manufactured Product

After you get an assembly house to put together your product: what are the typical approaches to install your software on every one those product? Is this something the assembly house typically do? ...
iCode's user avatar
  • 705
1 vote
1 answer
301 views

Soldermask bridge gap too small - PCBWAY

I've got a PCB design which contains a chip that uses the QFN (7x7) package. Because of the package size the pins are very close together and the pads are 0.2mm apart, which is smaller than the ...
bash-'s user avatar
  • 131
1 vote
4 answers
378 views

Choosing a PCB Manufacturer/Assembler for the first time [closed]

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 ...
Gabe S.'s user avatar
  • 303

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