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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Can 5mm UV LEDs cure solder mask?
Is it possible to cure solder mask using about 32 5mm UV LEDs spread evenly above a PCB (10x15 cm). If yes, since they are weak, what would the cure time be?
I want to make my own PCB mill and I want ...
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How to connect a removable multipolar signal flat cable to PCB
Wich is the best and easy way to connect this kind of cable to a PCB in a manner that it can be attached or removed to and from the PCB?
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Identical component on both sides of PCB with vias in ground pad
I have a dual analog output PCBA that I am routing. The analog output component selected is two TI DAC7750IRHAR DACs.
These DACs are controlled via SPI lines. I had originally intended to place both ...
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Soldering 2-Wire DC Motor directly to PCB
I'm making a PCB that's required to be pretty compact. In order to reduce overall size, I need to keep a 2-wire DC motor as close to a PCB as possible.
It has standard tabs on the back, typically for ...
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What files do you need for PCBA?
Just a quick one.
It seems that for PCB manufacture, the industry-standard way to specify what you want is so-called “Gerber files”.
If you want PCB assembly as well (i.e., loading components onto the ...
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Putting caps, resistors, etc on back side of board
Assuming I am ok with the extra cost of having parts assembled on the backside of my PCB, does it make sense to basically place all the main parts on the top side and then strategically place all the ...
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Identifying an SMD component
It is related to the USB bus voltage in a Delta HMI that has been damaged. Is this a 2.4 V Zener diode? This component is marked with the letter D311 on the PCB.
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How to add 2 or 3 parallel Li-ion cells to my custom PCB
I've tinkered with electronics and components for quite some time now, but I'm kind of a noob when it comes to taking things to "production".
I've this project using an ESP12-E, powered by 2 ...
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PCB hybrid stackup
Have you seen or is it advisable to use TEFLON (PTFE) material between signal and ground layer and use an aluminum core material for better heat dissipation? I am improving a 6 layer circuit board ...
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Are these tracks too close for comfort, will this distance cause any problems?
I'm doing some PCB wiring and I am connecting many buttons to an Arduino Mega's digital inputs. The idea is that the digital pins will be normally high and when I push one of the buttons, the digital ...
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PCB warping during Reflow
I have design a PCB size about 100x60mm it reflow very nice on the hot plate but If I convert my PCB to a panelization 2x3 quantities size became 200x180, the edges began to lift up due to expansion ...
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Could 94-HB board be used for SMD and THT soldering?
I have a circuit that I designed lately which is quite simple based on just 1 opamp and have an SMD and THT components (like a relay) and will be producing mass production in Chinese factories and it ...
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SMD button not in jlcpcb BOM
I want to try the jlcpcb assembly service.
I created the BOM, by using the bom2grouped_csv_jlcpcb. I inspected the generated file and indeed all the SMD components ...
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Replacement IC for SGM2212 LDO Regulator
I'm looking for a suitable replacement IC for the SGM2212-3.3XKC3G/TR found in this schematic. I've found this, which seems to be very similar and suitable for this application, but I'd like if ...
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Component/Footprint selection in EAGLE for PCB designing
I'm a beginner and I want to build a basic PCB using EAGLE software. I want to only use SMD components but I have few doubts while using EAGLE:
I want to design a PCB schematic by using standard ...
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PN532 RFID Reader IC taking up 4mA even when there is no power applied
I have designed a custom PCB for one of my side projects. PN532 is interfaced with ESP32 over i2c. Goal is to have the system consume current in uAmps range when in deep sleep. I put ESP32 in deep ...
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Need help figuring out circuit board design
I'm building a clock I found on Thingiverse. The designer created a custom PCB to connect three stepper motors, an Arduino Nano and some Hall sensors. Unfortunately there aren't many instructions. I'...
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Is it feasible to put solder mask cured on the top of tinned pads?
I made a batch of PCBs with a QFN package IC. I accidentally connected the pad to GND even though it should be either left floating or connected to some signals else. I am glad that I have requested a ...
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Excessive brown flux post reflow
I've been assembling low numbers of reasonably complicated PCBs professionally for a few years now, and while I can get good results eventually, one thing that's dragging the process out is the need ...
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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,...
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Fix for poorly designed class-D amplifier mute circuit
I recently made a PCB for a project with several class-D amplifier channels to drive small speakers for audio feedback. I included a mute switch which connected or disconnected one end of these ...
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Do companies usualy change PCB layout if they create different versions for different markets? [closed]
I was wondering what's common practice.
If a company like Samsung for instance creates a phone for the international market (SM-G975F) and the Korean market (SM-G975N), and the Korean phone has some ...
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Functional discrepancy within PCBA batch
When manufacturing a small prototype batch of an embedded system at EMS I have detected different behavior between the units. All units work as expected, except that some units fail to operate same ...
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Interaction between PCB surface finish (ENIG vs HASL), wave soldering, and manual final assembly
I am developing a PCBA that is (for me, an amateur) fairly complicated: 4 layers, double-sided, mixed SMT/THT assembly. It is a fairly dense layout with ~150 total components including all the ...
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Altium Variants In Bill Of Materials
Is there any way in Altium to display/combine the different Variant configurations in a single Excel sheet exported from the Bill of Materials, e.g. have the different variant configurations displayed ...
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Covering up PCB soldering pads
I have a PCB that I'm wanting to use just for stability purposes to hold other components. Basically, I want to put a stacking header on it (for a Pi) and then hot glue some modules to the top and ...
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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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