Tagged Questions

5
votes
1answer
250 views

Soldering 0.5mm pitch ICs using stencil and reflow oven

I'm new to SMD soldering, and tried to assemble a couple of boards, using a reflow oven. I 'm using a stencil (Kapton - mylar) and so far it worked fine except for the LQFP48 devices (pitch 0.5mm). In ...
2
votes
1answer
164 views

Tips for constructing small PCBs with only one SOIC

So I'm going to repackage this breakout module for simple SPI with a bus-powered LED light strip. It seems expensive and unnecessary for advanced SMT assembly equipment and since its a small PCB with ...
12
votes
4answers
395 views

What is the best way to short adjacent SMD pads?

Which of the three ways shown above would be the best way to short two adjacent SMD pads together, and why? These are TSSOP pads and the assembly process will be lead-free reflow, if that matters. ...
3
votes
2answers
200 views

Is this part hand-solderable, or will certainly require reflow soldering?

Here are the mech specs for the part (it is a GSM module) - Note that all dimension are in "mm". If hand-solderable do I need to keep some specific precautions in mind (from soldering ...
4
votes
2answers
248 views

Is it advisable to use lead-free PCB and solder paste on a first SMD assembly job?

I am sending my first PCB design to Sunstone for manufacture and I need to decide whether to order the board finish lead-free. All of the components are lead-free, and I have not decided on solder ...
0
votes
1answer
500 views

Why can't I find cheap TQFP 44 sockets?

I am trying to find a reasonably priced socket for a TQFP44 microcontroller but I am having a very hard time. The only I found so far is this one: ...
2
votes
2answers
194 views

extract components from SMD

I bought a cell phone in China (read chinese iphone), that despite the operational system is awful, when I opened to check the hardware and I found a not so bad hardware. I was able to extract ...
16
votes
3answers
1k views

Should I worry about the risk of tombstoning?

A colleague has (apparently unsuccessfully :-)) tried to convince me of the risk of tombstoning in the following situation: He claims pad 1 for R55 and R59 will lose heat faster during ...
3
votes
4answers
600 views

what is an average CPH speed for hand SMD assembly?

What would be the average speed (an experienced) person would assemble surface mount components on to a PCB? Assuming they have desk that is correctly set up (pick and place station) and the PCB has ...
6
votes
5answers
601 views

PCB copper thickness with small pitch SMT components

I typically use 2 ounce copper as rule for all my PCBs. On a recent board I am using a 0.5mm pitch, relatively large micro, and noticed the pads aren't very flat. Assembly went fine with the protos, ...
11
votes
8answers
1k views

Sizing SMD components for Hobbyist Kits

More components are only available in SMD packages. For hobbyist assembly the options are to buy breakout boards or solder SMD. Since components are usually packaged in a couple of SMD package ...