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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Flexible PCB design suggestion
I'm currently learning to design a PCB. For this board, I want to sense the current in two different ways (using either analog or digital current sensors). Each sensor requires a current sense ...
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Calculating minimum prepreg thickness to withstand high voltage difference between layers
I am considering doing a 4-layer PCB for a 3-phase system (400 V) for the first time (never done a high voltage board before).
Because of mechanical constraints, I want the board to be as thin as ...
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Hot glue for circuit boards
Is it a good idea/safe for circuit board components to be submerged in hot glue, in order to essentially "weatherproof" them to a certain degree? I don't believe the components will have the ...
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What are these legs to connect to an IC called on a PCB?
I am designing my first PCB and it is going to be designed to plug into IC sockets on a motherboard (replacement modern RAM for retro computers).
I was wondering what to use for the legs. Looking ...
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PCB Silkscreen Marking
Today, I came on a PC board and the silkscreen marking have TG on it. What is the component for TG?
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Is it OK to solder to large copper pour area
Is it a problem to integrate an SMD pad into a large copper pour area? In this case, the packages are 1206. I am wondering if I need to be concerned about thermal issues and interfering with standard ...
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PCB Design on width
I would like to construct a 25A on board. How much mil or mm should I use for wire width? I have search for it size shown that 300mil/7.62mm for 10A.
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How to predict costs for getting PCB assembled?
I have a PCB that I designed that has around 40 components (mostly resistors and capacitors) on a board that is 40 mm by 80 mm. I have the BOM, pick and place file, and gerber file. If I provide the ...
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Pick and place file from Excel
Further to the question here
I want to know how the centroid point is calculated in Eagle software?
Above picture shows the coordinates of the 2-pin SMD connector @ (51.7,26.4).
But when I exported ...
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SMT Reflow solder quality issue with SN42/BI58 paste
I have been doing hardware design and PCBA prototyping for a while and I have issues with quality of reflow soldering. I have a small lab including a pick'n'place machine, stencil printer (eC-stencil-...
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BGA Microcontroller Only Works with Finger Pressing
I have a PCBA with a BGA microcontroller on it. I found that two UART pins send/receive garbled output unless I press my finger down on the BGA package itself.
I've seen this on a few boards and I ...
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Placing components between DPAK IC pins
Is it accepted practice to place components between the pins of a DPAK IC like in this picture?
KiCad says "courtyard overlap" in the DRC, but this shouldn't be a problem, I think. During ...
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Clarifications about PCB assembly
I just finished designing my PCB, I printed it and assembled it. Everything seems to be working fine after some tests. However, assembling the load cells and power cables was really complicated and ...
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What is the best location for Top Component Center
When designing footprints of symmetrical components like SOIC-14, it is easy to determine the top component center, but where should be the best location for an unsymmetrical component?
Is top ...
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Missing solder mask opening on PCB footprint
I have three through-hole PCBs that are missing front and back solder mask openings for two of the components. The solder mask (usually green) is covering the front and back solder pads. All other ...
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AC/AC power supply for PCB
I am trying to source the right setup for powering this PCB:
I have found an 18 V AC/AC power supply but it has a barrel connector:
I am struggling to work out how to connect the barrel connector to ...
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Washing of an IC
Can someone tell me what is the information regarding the process of washing the device during production?
This question is with respect to the Microchip LAN8741A
user220456
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How does PCB manufacture work for double sided SMT assembly with BGA's?
How does a conventional board house deal with the issue of reflow during PCB component assembly with BGA's on both sides of the board?
Are two different solders used (like regular lead free SAC305 and ...
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Solder reflow pure nickel strip to PCB ENIG pads
I've arranged for a custom shaped strip of pure nickel that I intend to solder to ENIG pads on a PCB using reflow/paste.
Will we have problems getting the solder to adhere to the nickel? Is there a ...
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QFN-28 REVERSE Breakout Board
I am trying to build a PCB board that I found on GitHub. In a rash we ordered few sets of the PCBs without inquiring about the parts availability. Turns out one of the parts is not available in all ...
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SMD pad size for custom component
I'm trying to reflow a custom shaped strip onto a PCB, but I'm unsure about what size pad I need on the PCB.
The strip is 13mm x 6mm x 0.3mm.
The PCB surface finish is ENIG.
The pad is likely to be ...
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Can you attach a connector meant for a rigid PCB to a flex PCB?
Is it possible to connect a standard mezzanine connector to a flex PCB?
I.e. could I use a mezzanine connector meant for connecting two rigid PCBs in a situation where one is flex and one is rigid?
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Is there another component on the pcb that will extend the leg of the component?
In order to realize the event I mentioned in the picture below, I need an auxiliary component. Maybe a component where I can extend one of the holes 5 mm to the side. Or 5mm to 10mm dip adapter. Is ...
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How to connect 2 (and more) PCBs together to make them semi-modular? [closed]
So, I want to design PCBs with some LEDs on them and connect them together. The PCBs are about 2 cm wide and connection has got to be on this sides of the PCBs. I've tried some connectors but ones I ...
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What's the best way to solder these fine pitched connectors/pins?
During a replacement of a camera mother board, I managed to screw up one of the ribbon connectors, by tearing it right where the ribbon slides into female slot. I am unable to find any replacement ...
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Point-to-point building of medium- frequency circuits, ground plane implementation
I build audio projects and small logic control circuits using point-to-point on perfboard (see pic of a recent build).
As you can see this allows me to select wire gauge in accordance to the currents ...
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INA219- I2c bus weird behavior
I have a PCB assembly where I built the circuit in the schematic below. I did not start programming yet.
I'm getting the weirdest problem. When I check the voltages in the SDA and SCL lines (which ...
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Reflow soldering with temperature-sensitive components and without a reflow oven
I need to assemble and test a rather large (40x30 cm) board with single sided SMD parts, Sn Ag Cu solder (officially 217°C melting point). Usually I place group after group of components and locally ...
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2 Layer PCBA routing strategy for high current design
I have a very simple pcba design. The only thing of value is that the traces will carry up to 30A of current.
I have already decided to increase copper thickness to 2 oz for improved current capacity.
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Is there any difference between Silicone and RTV
I've used silicone RTV that's intended for use on PCBs and have also used 100% silicone purchased from the hardware store to use on PCBs. I was not able to tell a difference between the two. ...
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