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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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 ...
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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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Split / combine a larger printed circuit board from smaller boards
I have plans for a large PCB (~12".) Some sections of this board are modular - they have a very similar design. To lower the price, is it feasible to split one big board into smaller, modular ...
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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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adhesive glue before soldering
Before I solder very small electronic parts on PCB board, I want to find some needle point sized injector to inject tiny glue fix the parts, then do the soldering.
Some manufacturers used that, but 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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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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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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Protecting circuit boards against shock?
Our company have been designing and manufacturing custom circuit boards for some 10 years now, and up till now by far the most common reason for board failure has been a mechanical shock - heavier SMD ...
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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 working ...
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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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Can you tell me more about "re-enterable" potting compound?
I heard the term "re-enterable potting compound", which is a gel-like (possibly hard?) material that can be used to fill electronics enclosures for water intrusion protection and other things.
What ...
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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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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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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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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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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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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 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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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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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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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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PCB assembly cost per-board
I know this question might get closed because of being opinion depended but I couldn't find any answer from google or any other search, so I decided to ask it here.
For clarity of question I want to ...
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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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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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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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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 ...
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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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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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Is it okay if I undo traces in EasyEDA?
I'm new to PCB design. I am using EasyEDA. I'm currently designing a PCB with around 50 connections. I did 48 of them myself and ran the AutoRouter for the other two. The AutoRouter has made the ...
CommunityBot
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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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