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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Generic packages for assembly tests
I'm thinking of getting a pick and place machine, however I need to test the capabilities of the thing, to make sure it actually performs properly for the given task.
The idea I have is to send some ...
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Need for cleaning solder residue for 7mm spacing due to breakdown voltage
I've designed a board that I ordered from JLCPCB. I have traces with 7 mm lowest spacing between them and with voltage of at most 400V AC, 525V peak between them.
The traces couldn't be wider due to ...
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Can functional diodes and capacitors be printed on a PCB instead of soldering?
I want to print a fractal, capacitor circuit, network using diodes in strings of 3, with 2 capacitors in each circuit. The goal is to get 96 capacitors and 144+ diodes on the board. That is a lot of ...
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Single components vs. IC Arrays
Beginner Question: I've seen boards that have 4/8/16 identical resistors in a row and boards with an IC containing the same number of resistors doing the same job. Same with diodes, transistors, and ...
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PCB mounted (soldered) pluggable Pins or Terminals
I'm trying to design a PCB that is pluggable into another PCB, each one being inside separate plastic enclosures. I'm having a hard time finding a component that I can solder on a PCB and that can ...
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Is it possible to replace the colour sensor in a Spike Prime colour sensor?
Based upon this post internals of spike prime colour sensor, is there an RGB sensor that I can replace the TCS3472x (unknown on which option) sensor present in the colour sensor with?
If so, is it ...
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How am I supposed to solder this tiny component with pads UNDER it?
My phone's microphone recently stopped working after falling. So I decided to try to repair it by buying this component (I guess a single microphone is in my phone, an xcover 4s, since calling with &...
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Is it normal to be able to tear off PCB components with bare hands? [closed]
I just ordered 5 boards from a popular Chinese PCB manufacturer and (for the first time ever w/ with this manufacturer) some SOD-323 diodes and their pads and adjacent tracks were peeled off out of ...
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Altium Tracks Automatically Roll Back During Interactive Routing - Why?
I'm trying to increase the copper area across the through-hole pad in Altium Designer to prevent damage during soldering and desoldering. However, when I'm close to completing the track, it ...
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USB A mechanical orientation?
This concerns a USB A socket on a PCB.
Is there a standard or preferred orientation of the polarization tab, either up or down?
The picture shows one with tab towards the top
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What is the best solution to keeping heavier components on a double-sided PCB while going through second pass reflow?
I am trying to do some research as I have many customers who face this issue with their parts falling off the board during the second pass. What has worked for you? Many applications are different ...
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Unknown SMD component - PCB Designation question
I have a board we are trying to repair. We are unable to get any technical documents from the manufacturer, no schematic or BOM for the board. This has multiple switches, think metal dome you press ...
user388256
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Attaching foam to the bottom of a PCB
I'm currently designing some development boards that are quite large, around 100x180mm, with lots of through-hole components. The goal is to create an educational tool for students. Because of this, I ...
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Identify 5 pin smd marked "KV.." from motherboard led tv Panasonic
Identify 5 pin smd from motherboard led tv Panasonic that burned.
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What is the best way to adapt a larger connector when the insertion holes on the PCB do not match?
Good day, everyone. I have a Type-C connector on a device that is much larger than the micro USB connector I had previously. The insertion legs do not align with the holes on the PCB, and since it is ...
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Reattaching DC power adapter jack to PCB
Recently, my baby monitor stopped charging - that is to say, when I inserted the DC power cord, I had to wiggle the plug about in the socket a bit to get in to start charging and even then it was ...
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Is it possible to create new footprints and integrate additional components into an already manufactured PCB?
What is the most effective method to do so? I have enameled wire, which seems safer to me due to the insulation. My plan is to cover them with solder mask. However, I have a question: Would it be ...
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STM32F4 TQFP100 part orientation
I have mounted a STM32F446VETx on my PCB as shown on a picture of my PCB:
For me the pin 1 marker in the big mark at the top right of the picture, near C67.
But, after a lot of trial, I can't connect ...
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What is the best solution for wire to board then board to board connection?
Background: Hello, I am a first timer trying to finish this PCB redesign. I am in dire need as an intern who has no clue what they are doing but is having fun learning.
I have all my schematics ...
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Any idea how to stack two PCBs that can work independently
This is my first time ever doing PCB stuff :D
I have two L-shaped PCBs that will stack on top of each other. The connectors would stack on each other so that it can either:
Be used with both top and ...
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Are there any techniques for soldering USB-C 16 pin?
I am trying to solder Type-C SMD USB connectors but I can't do it properly. Despite using an SMT stencil for soldering, each time I am having an issue and I can not solder it properly. Sometimes pins ...
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Can I treat the thermal shock test temperature as the continuous operating temperature of a conformal coating?
We are using this conformal coating on our design, HumiSeal 1B73EPA.
However, it does not state in the datasheet the continuous operating temperature for the coating, only the thermal shock test ...
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Any software for helping hand place components by listing 'by group'? i.e. all 10k resistors so they can be placed at one time
Sorry for the convoluted title but what software do people use when placing physical components on PCB's?
Looking for something to highlight all 10k resistors or 1nF capacitors as examples to speed ...
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CJMCU-3652 resistor dimensioning
I bought a CJMCU-3652. It is based upon the LT3652 from Linear Technologies. In the datasheet on page 15 there is a description on how to calculate the resistors to properly
charge whatever battery ...
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Using TO-92 package for high voltage applications
I'm looking to build a high voltage (but low current) current source and I see transistors rated at 500V in a TO-92 package. The leads aren't even bent so spaced 50mils/1.27mm apart, and when ...
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Acceptable: Polygon/zone over surface-mount (SMT) pads?
Will placing a copper polygon/zone over multiple (same-net) surface-mount (SMT) pin-pads create any thermal issues with the solder (for example, paste not sufficiently heating up)?
The solder mask ...
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Are the diodes and capacitors oriented correctly in this motor driver PCB? TMC2209 stepper motor driver
If the polarity of both diodes and both caps look right, the driver IC probably smoked because of my solder job.
Datasheet:
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How do they make PCB with 0.2mm tracks? [duplicate]
I want to understand how do they make PCBs with 0.2mm tracks. I have built PCB using screen printing process. As screen print requires 0.5mm minimum track thickness, I need to keep track wider. ...
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2D mapping of PDB Layout in Allegro
I am trying to export a 2D drawing of my pcb layout in allegro. I would like the layout to include the components and their reference designators. However, I cannot find a way to do so and the ...
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PCB Layout review: ESP-07 with 28BYJ-48 Stepper board
I have used the 28BYJ-48 in conjunction with an ESP8266 in some applications and I thought it would be handy to have pcb made. I want to use JLCPCB including Pick and Place.
The Kicad source code is ...
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Footprint pads for an RF chip in QFN package
We are working on a design that uses the Analog Devices HMC321A. The datasheet does not specify a recommended footprint; they do specify the IC dimensions. The pins/pads on the chip have a nominal 0....
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How to solder a 5.5x2.1 DC plug to a PCB?
I am looking at mounting a DC plug on the side of my PCB board.
Unfortunately, only jacks exists for purpose of PCB mounting, and there are no mountable plugs produced.
(if they existed, they would ...
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What should be the minimum number of SMD components on a reel (minimum tape length) for a pick and place machine?
What should be the minimum number of SMD components on a reel for a pick and place machine? Different scenarios are possible for each machine. In terms of professional machines, if everyone writes ...
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PCB design - Routing without a schematic
I am using Altium CircuitMaker to design a PCB. I'm wondering if there's a way to make my PCB design without a schematic.
My idea is to simply make a PCB with just pads and populate it myself with the ...
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PCB Design Process
I'm new to PCB Design so I wanted to clarify a few things about the process.
For context, I have already physically made my project on a breadboard. Now I am trying to lay it out on a PCB.
I have ...
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How do you align parallel connectors (e.g. Raspberry Pi CM4) in production?
Apologies if this seems like a duplicate of this question but the eventual "answer" to that seemed somewhat anecdotal at best - and there's been a LOT more of these used since 2012 so things ...
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Is pad against pad enough for a good connection?
I have two PCBs that I need to connect together with holes or notched pins that I have to solder by hand.
In order to reduce soldering time, I've placed a few 2mm square pads on the bottom PCB and I'm ...
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Production quality issue?
I had 5 two-layer boards fabricated by a popular assembly house in China and I'm curious what folks thoughts are based on what I received.
Here is a photo of the 5 boards which has a red square around ...
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Diode and bipolar NPN transistors orientation not correct, says JLCPCB
JLCPCB is telling me 4 components are incorrect but when I look over it and the datasheet it all seems correct to me.
My original | JLCPCB corrected:
This is what my current board looks like:
My ...
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Supplier advising age of 74HC173 SOIC parts
I put in an order for 50 Nexperia 74HC173D,652 with JLCPCB for some kits I'm having built and assembled by them. These are going into electronics kits that are sold to high schoolers as part of a ...
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Is this USB C connector with tight pads too risky to use?
I'm intending to use the following vertical USB C connector because the long board overhang fits requirements, but the footprint causes some concern, not least because it seems to violate JLCPCB ...
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Importance of copper balance when dealing with small components (0402, 0201)
I usually work with big components (0805, 0603.) Now I'm trying to make a board that would use much smaller packages such as 0402 and 0201.
I know that balancing copper is relatively important to ...
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Why are some components missing areas of pour near mounting holes?
Circled in red are component through holes in a copper pour plane that are missing areas / don't have the copper poured completely around the via. Seen on tons of components both through hole and ...
user298907
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Trying to ID small barrel component for replacement repair
I am trying to find a replacement part that goes on a PCB of an LED C size battery-driven hanging lantern light. One of the two leads of the small barrel shaped component corroded and broke off near ...
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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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