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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4
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1answer
149 views

What is this foreign material on my outsourced PCB?

I had this board populated by an EMS house. There is foreign material around some of the pins. They don't know what it might be. Our collective best guess is that it is somehow shavings from the ...
2
votes
1answer
99 views

Is it bad to route a trace edge of a rectangular pad?

I got a quick friendly critic from someone in production for the below trace that I should not route the trace from the edge of a pad. What he said that it would create an extra force to the trace ...
2
votes
1answer
48 views

pick and place cannot read LCC module

The assembly house has a P&P machine (Yamaha i-pulse M4S) and the export file is from Altium. All components are read from the machine fine except an LCC gsm module MG323-b which has a particular ...
1
vote
1answer
68 views

What is the proper zero orientation for a SMT LED?

What is the proper zero orientation for a SMT LED? According to screaming circuits and IPC-7351, the cathode should be on the left for a molded diode. HOWEVER, when I use Altium's component wizard to ...
9
votes
2answers
658 views

Strange Solder Spots on PCB

I was tearing down some old CD drives and while taking a look to the PCB I found two pointy solder spots, connected to the first pin of each side of a chip which makes me think is an EEPROM. There ...
2
votes
2answers
278 views

Why we need the PCB Panelised for assembly?

I have a PCB finished in invidividual size for customer but they gave me comment that it can't be used by their assembly vendor and ask me make the new batch for them, When we make the board in 2 up ...
2
votes
1answer
79 views

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 ...
1
vote
0answers
108 views

Single- vs double-sided PCB assembly costs

I'm working on a new design (still laying out the components) and I have a chance here to reduce the size of the PCB by roughly 40%-50% if I use the other side for a QFP-100 IC (so it's heavy and will ...
0
votes
1answer
127 views

Suggestions for in-house PCB/FPC lab? [closed]

We are a hardware startup based out of Greece, looking for in-house PCB/FPC fabing solutions/equipment. LPKF's ProtoLaser U3/S look great but they cost $140K and $70K (if I'm not mistaken) ...
3
votes
3answers
289 views

Solder Mask and Pad Area (SMD vs NSMD)

I have been trying to figure out the "right" way to size pads for surface mount components, and I have found some conflicting wisdom floating around the internets. Lets say I have this hypothetical ...
0
votes
1answer
296 views

Smallest possible PCB size for TI CC3200 [closed]

I'm just getting started with hardware side of Computers. At this point, I'm really interested in TI's CC3200 Network Processor, which has an integrated CPU to allow me to run custom code. You can see ...
1
vote
3answers
122 views

Creating with BGA

I have a project that I've begun to work on, it's sort of an embedded PC type project, with a iMx6 arm processor. However, since this is a (potentially) commercial venture, we can't use prebuilt ...
3
votes
1answer
202 views

Testing procedure for a PCB

I have a little bit of experience with PCB design and made a couple of small circuits for learning purposes. I need to test out a new PCB designed by another person and its kind of a complicated ...
5
votes
4answers
123 views

Export restrictions when sourcing parts for PCB assembly in foreign country

If a company has a PCB design and wishes to assemble them economically, a natural choice is China. Some Chinese companies are asking for the parts (or some of them) to be shipped to them. This means ...
1
vote
4answers
350 views

Holding components without bending leads when soldering upside down?

I am gaining experience in soldering components onto PCBs. I'm working through some one sided through hole PCBs and one thing that I'm having trouble with is holding components once I flip the board. ...
5
votes
1answer
137 views

what lead-free solder type is convenient to use on hand-soldering?

I have read some discussions about the lead-free solders on the forum, but could not see what solder type is easier to use on hand soldering (for lead-free ones)? As an example, I see only two RoHS ...
0
votes
3answers
182 views

How to troubleshoot soldering issue?

I have circuit working perfectly on a breadboard - motors are spinning as expected. But same circuit with same components is not working when I soldered it - motors barely can spin (you hear buzz ...
0
votes
2answers
72 views

Is airbath + air gun reflow appropriate for low-volume commercial production?

I understand there are a number of ways of reflowing individual SMT boards. I've seen small temperature profile ovens, hotplates, skillets, airbaths, and hot air guns used. I'm trying to determine ...
2
votes
1answer
85 views

What is the value of x-ray inspection of an assembled PCB?

I've heard discussion of x-ray inspection of assembled PCBs. I understand this to be useful for things like BGAs, where there's no other way to inspect all the solder joints under the package. Is it ...
7
votes
3answers
347 views

When is it OK for connectors to be SMT instead of TH?

A lot of boards with predominantly SMT components have TH connectors on them for things like headers and power connectors. Take a standard barrel power jack for example: TH: SMT: When designing ...
4
votes
3answers
158 views

Do pick & place machines require reels of components, or can cut tape be used?

If I wanted to have a PCB assembled, would I have to give the manufacturer reels of components, or will pick & place machines also work with cut tape? I ask because I'm thinking of having a low ...
7
votes
3answers
246 views

What rules and tips make automated assembly easy?

What rules and tips make automated assembly easy, rather than unnecessarily difficult or completely impossible? In particular, if I have a circuit board that works fine after hand assembly, some ...
5
votes
5answers
614 views

PCB fabrication vs PCB assembly

What is the difference between PCB fabrication and assembly? Some companies like Golden Phoenix list that based on the size of PCB, it outputs a quote. Mine was 2.1 x 1.6 inch. It outputted 29 pieces ...
2
votes
2answers
128 views

How to know which side of the terminal block on pcb drawing

I'm planning to use Seeed's PCBA Prototype, where they request to use their open parts library(if you want them to solder the parts for you). I came across their screw terminal block(part 3470070P1). ...
0
votes
0answers
55 views

Pb-free reflow soldering of thick packages on PCB

We have a PCB board with approx. 600 SMT components (various IC, passive components, etc.). This board is to be assembled by our manufacturing house and they do use a reflow oven to solder our ...
2
votes
1answer
141 views

How do different kinds of vacuum pick-up tools compare?

My company has extensive experience assembling through-hole PCBs, but relatively little experience with SMT. I've just been introduced to the idea of vacuum pick-up tools for SMT components. (Examples ...
1
vote
1answer
131 views

How are headers soldered in PCB assembly?

During large-quantity PCB assembly/soldering, are SMD (surface-mount) headers traditionally easier or harder to assemble than DIP (through-hole) ones? By easier/harder, I'm concerned about ...
-1
votes
2answers
107 views

cylindrical pcb design and casing

I'm trying to desing a control system that measures some analog signals like differantial pressure, temperature, motor current etc... and then produces some control signals and sends information to ...
1
vote
1answer
102 views

Correcting printed PCB (add a via)

This board is a prototype for the project and is for testing. It is missing the soldermask and silkscreen layers, so correcting mistakes is very possible. The board was printed correctly, but somehow ...
0
votes
0answers
32 views

What is JTAG TCE signal designed for and what effect does it have on the boundary scannable IC?

I know for fact that some boundary scannable ICs don't have this JTAG TCE input signal but some does. Does any one know why?
3
votes
1answer
215 views

How to solder a connector when spacing of PCB pads is not equal to spacing of component pads?

After delivery of my PCB, I realized that the spacing of PCB pads is not equal to the connector pitch (the PCB footprint is bigger than the OLED connector)! (sad) Look: Any idea how to solve this ...
4
votes
5answers
1k views

Any tricks to attaching a wire or pin to a testpoint?

More and more often, I find myself needing to tear apart a device to seek out and connect to serial pads. These pads typically give me access to the underlying operating system for research or ...
3
votes
1answer
151 views

Accidentally used plumbing flux on a PCB; How do I remove it to reuse the board?

Two weeks ago, I picked the wrong tub of flux from my toolbox and used it for making a 9VAC -> 5VDC adapter. I fluxed all the components and soldered it down before realising I was using PLUMBING ...
2
votes
1answer
108 views

Moisture Senstive Devices - Shelf Life

I have a bag of DAC7512N digital to analog converter from TI. They are still sealed in the original packing, however the caution notes denote "calculated shelf life in sealed bag: 24 months" and the ...
10
votes
4answers
699 views

OK to connect boards perpendicularly like this?

Are there any disadvantages in using the following method to accomplish a perpendicular board-to-board connection? (i.e., any disadvantages in terms of board manufacturing capability/cost assembly ...
3
votes
1answer
207 views

ATmega2560 not responding on hand-assembled PCBs

I've assembled some PCBs that I had made, and I'm unable to get the ATmega2560 to respond to programming via the ICSP header. On the third board I'm trying, I have soldered on only the MCU, the ICSP ...
0
votes
1answer
272 views

How to hand solder pads underneath an IC? [duplicate]

I have to design a board with a package case called MSOP-16 It has a large ground pad underneath the IC. What are good methods for soldering this pad by hand with a soldering iron? Since it is a ...
2
votes
1answer
223 views

Is there a pitch limit to applying solder paste through a PCB stencil by hand?

I've ordered two stencils from two different companies, two different materials. Both times I've been completely unable to effectively apply solder paste to the pads of a QFP-64. I end up with a mess ...
2
votes
2answers
4k views

How to re-solder fine broken flex cable connection to pcb

I have a phone where the volume button button flex cable has been partially pulled away from the PCB. See this photo for what it would have looked like before being damaged: ...
0
votes
3answers
111 views

What is the optimal way of clearing solder from surface-mount PCB pads for rework?

Say I have an assembled PCB with a QFP package on it. This device gets damaged and I need to replace it. Getting the device off is straightforward, but now all the pads have solder blobs on them. Is ...
5
votes
2answers
362 views

What stages do PCB mass-assembly techniques come in?

There's a spectrum of how you get PCBs assembled. 1) Have a human pick out all the parts, solder them all on by hand, and check them all by eye. Low cost of entry. Good for low-volume high-mix work. ...
31
votes
4answers
2k views

Securing electrical cables to holes in enclosures?

Suppose I would like to insert data-cables of varying diameters -- e.g., a cable of 5 mm diameter -- into the 6 mm diameter hole of a plastic enclosure. The wires within the cable are terminated via ...
1
vote
1answer
105 views

What kind of failure would I see in moisture sensitive parts?

I am reflowing a design using an electric skillet. When the uC and LEDs arrived they were in moisture sensitive packaging. They were in sealed bags with moisture indicator cards. After I opened them I ...
2
votes
1answer
551 views

External crystal not working

I have designed a PCB for a PIC32MX795 chip. (Datasheet) I want to use an external crystal (Link to datasheet in PDF) but when I solder the crystal to the board, I can't get my PLL to lock to 80MHz. ...
2
votes
2answers
218 views

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 ...
2
votes
4answers
3k views

How do I solder this USB Connector?

I bought this micro usb part: I need to solder it to a PCB that I designed, but I'm having a ton of trouble figuring out how to do so because the tabs are very close together and hard to reach. Is ...
3
votes
2answers
1k views

Eagle configure autorouter to solder components (except vias) only on bottom layer of double sided PCB

In double sided PCBs it is difficult to solder through hole components like IC bases, headers, etc. in the top layer. Normally the Eagle autorouter places the solder pads on both sides. That is, in a ...
8
votes
1answer
355 views

What are these spots on the PCB that are by the mounting holes?

When you look at the board, there is a weird part of the PCB right of the top left mounting hole. There is also another one above the top right mounting hole. ...
9
votes
3answers
668 views

Circuit works on breadboard but not PCB

I have a fairly simple circuit that works perfectly on the breadboard, but I am having a lot of trouble transferring it to a PCB. I am seeing very strange behavior which lies outside of my current ...
3
votes
2answers
551 views

OK to connect ring terminals directly to a PCB?

I am designing a PCB board and was wondering if there is a reason not to use ring terminals directly to a PCB. The PCB could have a pad surrounding a hole like I often see as ground connections. A ...