Saturday, May 03, 2008

Rough guide to surface mount soldering

smd.jpgI share an interest in good quality headphone audio with many including Alastair who purchased the board and parts for the Alien DAC. Not being too confident with the soldering iron he made a deal, he bought two sets, one for him and one for me, if I'd help him construct his one.

Surface mount components are either tiny themselves, like the resistors and capacitors, or if large, they have pins that are very close together and hard to avoid having the solder bridge between them. The move to computer manufacturing with surface mount components is unfortunate for us home constructors. Some parts are only available in surface mount packaging and I fear for the future of this fine past time.

I got both boards going and thought I'd share my tips on construction, which you can see from the image are not too good, but serviceable.

For the chips with many pins, hold down the chip with the point of angle ended needle nosed pliers (the weight of the tool will hold it in place - hands shake too much), tack solder one corner pin and one on the opposite corner, then remove the pliers. Just flow solder across all the pins on each side, then go back with fine solder wick and suck back all the excess solder.

For resistors and capacitors again use the point of angle ended needle nosed pliers to hold them in place while soldering one end.

I think I'll put my new audio output device in a nice box along side a powered amplifier as covered in the past. Thanks Alastiar for the bag of bits!

2 comments:

Alastair said...

No, thank youfor building it.

This project worked out extremely well. Although progress was initially a bit slow, we got it going without too much fuss. When I say "we", I mean mostly you.

Totally agree about the problems of surface-mount technology. It also made troubleshooting slightly difficult too, as in getting an accurate reading from the multimeter.

Peter B Marks said...

I appreciate the company and the headphone interface. You did solder one of the components I recall.