Questions tagged [pcb-fabrication]
About the manufacturing of PCBs (Printed Circuit Boards).
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What is Copper Thieving and why use it?
On many boards I've seen, there are little copper dots used for the purpose of "Copper Thieving". They're small round copper dots connected to nothing and arranged in an array. Supposedly they're for ...
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Best One-Off DIY PCB Creation Technique
I have finally built up a lab to design electronics in. I have quite a few designs I would like to test. I have tried the printer toner/iron technique a few times but have found that I cannot create ...
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How to prototype?
How is prototyping done in a professional EE environment? Do you do your prototypes on breadboards, on copper clad boards, Manhattan style, or do you just draw schematics, order PCBs made and ...
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Air gap on isolation space
The below photo belongs to a PSU. I wonder what was the reason of placing air gaps on the 8 mm isolation. Is it to improve the isolation or provide a thermal relief (although there is no component ...
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Mounting hole on a PCB
Here is a picture of 3 mounting holes on three different PCBs.
The red one is what I prepared on Eagle CAD and used "hole" button on the left side menu , something like this:
Do I need to use "...
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Are acid traps real? (2014)
Some people online say that acute angles in trace routing will cause these problems:
"Acid Trap" - PCB etchant gets stuck in the corner, and eats away too much, causing open circuit
"Peelable" - ...
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What is the purpose of holes on edge of the PCB?
Here is a photo of one of Texas Instrument's RF EVMs.
Please pay attention to edge of the PCB that has multiple tiny holes. I marked 3 of them with a red circle on the photo.
What is the purpose/...
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How do you cut PCB?
I just spent about 20 minutes trying to cut through a PCB with a hacksaw. These things are really tough.
What is the correct tool to cut PCB material, and get a nice straight line?
I saw something ...
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Anything bad to place a via on a pad?
Once I mistakenly placed a via on 0603 pad and didn't have any problem on soldering. I am routing another board now and I could save some space by placing some vias (0.3mm) on a 0603 pad. I wonder if ...
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Are core and prepreg dielectrics interchangeable?
This is a followup to an earlier question.
In my experience, PCB fab houses always default to using prepreg and foil on the surface layers. For example, on a six-layer board, the stackup would be ...
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Is it advisable to use lead-free PCB and solder paste on a first SMD assembly job?
I am sending my first PCB design to Sunstone for manufacture and I need to decide whether to order the board finish lead-free. All of the components are lead-free, and I have not decided on solder ...
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What is a suitable temperature rise for PCB traces?
I'm designing a PCB for a 10A relay and am trying to determine what the trace width should be.
According to this trace width calculator, the biggest factors in the width are copper thickness, ...
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Is there a standard PCB Array Size for PCB Assembly?
I am planning on use various PCB assembly houses to get my boards PCB assembled. To minimize process costs, I am told it is best to panelize/array the PCB such that there is multiple boards per array, ...
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How common is it to receive PCBs with failed or weak vias?
This question is a follow up to Can chips be sensitive to mechanical stress after an electrical incident?. It turns out that our problem was nothing to do with failed chips. It was the PCBs all along.
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PCB opaque coating for anti reverse engineering?
Im trying to find a coating for my PCB in order to protect it from reverse engineering. I want it opaque, non-conductive and with a low thermal resistance.
Basically I do not want that someone ...
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