Questions tagged [pcb-assembly]
The process of mounting electronic components onto a printed circuit board. This can be done manually with a soldering iron, or automatically using a "Pick and Place" machine.
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I2C interface frozen until reflowed again
I have custom PCB with nRF52832 MCU and two I2C devices sharing same bus, IAM20380 on 0x68 and IAM20381 on 0x69.
All works fine, but after a few hours of testing I2C interface freezes when I2C command ...
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Drill through PCB or just use glue to mount component?
For a one-off hobby project I want to add a potentiometer to an existing two-sided PCB. There is an unpopulated zone (as far as I can tell) on the PCB that looks ideal, but I'd have to drill mounting ...
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Circuit Board Troubleshooting [closed]
The question is: "Where can I get circuit boards tested or troubleshot?"
As My profile shows, I am not an EE, but I'm forced to play one at my company. The following is just some background ...
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How do I find the center of a part when making a footprint for a component that will be used in a centroid file?
Often the footprint I need is not in the existing libraries and I need to make my own. For example one of the dozens of micro USB footprints.
When I make a footprint and then send for assembly at ...
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PLM management and PCBA numbering strategies [closed]
I was wondering if people here have their own ways of board numbering and how they keep a track of it? For e.g Unique Number-Revision Number-Board Description.
I have used team centre in the past to ...
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Question about assembly with DIP packages
I'm sending a board for assembly with a through-hole DIP-8 package with a standard horizontal lead spacing of 7.62mm. However, at their ends the pins are wide with a pin spacing of ~8.47mm. Should I ...
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Using ground plane between components on top and bottom layer
I’ve recently been reviewing some PCB designs to learn good practices.
One thing I’ve seen is that a ground plane is used on top layer between the components and traces.
Is this a good practice and ...
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Why do I have shorts/bridges on QFN packages on PCBA during assembly? Stencil Printing problem
I am trying to do a home assembly of PCB but I have issues after reflow soldering. Especially I have bridges/shorts on the pins of QFN packages. I have assembled multiple boards other joins are okay ...
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Cement Power Resistor PCB Mounting in Vibratory Environment
I'm looking to use a cement type wirewound power resistor on a PCB. We need the short term peak power capabilities that this type seems to provide. It seems the most common are thru hole type, like ...
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TMUX1119 SC70 package first pin identification
I have a TMUX1119 with an SC70 package.
The datasheet says there is a dot near the first pin. The actual device that was received is shown below. I can see a line and below it is written 1DF.
Which is ...
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Recreating Arduino UNO - PCB design (How are the components connected?)
I'm trying to recreate the Arduino UNO in order to be good at PCB design via EasyEDA or Altium. I have recreated the Arduino Uno schematic and design but it is hard for me to figure out few things (...
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Solder SMD on through hole
Can I just solder an SMD part directly on the through holes of the PCB?
The pitch of SMD matches the pitch of the through holes.
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How does the number of PCB layers affect the temperature of the board?
I understand that a PCB with the exact same circuit on a 2-layer board will get hotter than a higher number board: 4-,6-,8-layer boards. But, I have not been able to find the reasoning for this ...
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Tips for placing small SMD components onto PCB
I am trying to assemble a PCB that has very small components, an example datasheet is below. I am using tweezers, microscope, and a stencil to apply the solder paste. But this is no match for shaky ...
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Layer thickness design for 4-layer boards
I'm designing a 4-layer PCB, containing a GPS module (u-blox NEO M9N) and a Taoglas antenna. The GPS antenna should be on the top layer, and the GPS receiver should be on the bottom layer.
Besides the ...
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What to do with a missing common pin for a DC DC module on a PCB?
I made a big mistake while designing a board and it was printed out with 4 pins for the MDD02L-05 instead of 5.
What can I do with the common pin on the isolated converter?
I think folding the pin is ...
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Untented via close to ground paddle
I have designed a board and found an open (untented) via very close to a ground paddle as shown below -
The via in question is DVDD12 (shown to the center-right. I am going with a stencil based ...
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KiCad clearance vs JLCPCB clearance
From [JLCPCB][1] it lists many type of clearances.
However in KiCad, it only lists one type of clearance, and I don't know what it is.
0.5mm is the highest value for clearance in JLCPCB and in KiCad ...
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PCB microscope digital zoom vs optical zoom
I am looking for a PCB microscope and am noticing that there are many affordable digital microscopes out there that offer 1000x+ zoom. Is this enough to see very small details on a PCB, like inspect ...
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Clearance between SMD components
I'm designing a compact PCB.
It consists of non-addressable 5050 RGB LEDs.
I'm concerned about how close they are. I'm going to use the SMD assembly service provided by JLCPLB.
Should I change the ...
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How to solder two-sided PCB
I am getting a small pick and place machine with a reflow oven. I am wondering how can I reflow two-sided PCBs.
I have read many methods on the Internet like use two soldering pastes with different ...
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What could have caused this SMD capacitor failure?
I have an 0805 capacitor that has failed short circuit on a board. The maximum voltage it would see should be 16V. It has value 4.7uF, is rated to 25V and is X7R.
I don't understand why it might have ...
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Is there a component that will provide an elevated SMD pad?
Is there a surface-mount component I can put on a pad, that simply has another pad on top that I can solder something on to?
Here is a side view showing pins above the pads that would need bent down ...
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Why use kapton tape?
I have noticed a lot of electronics use kapton tape in places where a heat resistant tape isn't necessary. Why is that so? Is it just because it's a good adhesive?
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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 ...
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How close the soldering joint for pcb?
I am soldering a 5-12V 5-8amp max electronic to a pcb board, without a schematics. I just want to ask how far should each joint in PCB board? what I mean is for example a cathode and anode when ...
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Heat sink installation in pcb production
If a design calls for a heat sink, such as on a TO-220 package, is it normal for an assembly shop to install it during production, or is that something that generally needs to be added on afterwards ...
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ACF bonding with vias on the pads
I plan to use ACF bonding (hot-bar) to connect a display panel to a simple FR4 PCB.
As the circuit is very small and space optimized, I've positioned vias on some of the pads. If I would do use re-...
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I can't get a through hole diode to work on mechanical keyboard PCB key
I'm not experienced in electronics or soldering.
I find myself soldering the components of a PCB from a mechanical keyboard, all right and smoothly, except for two keys.
When I use the multimeter in <...
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Circuits : Simulation vs Real World [closed]
I'm asking this question to help many others (specially starters) to have a better understanding about differences that may arise between theoretical/simulation results and real world circuit ...
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