Introduction: SMD (surface Mount Device) Soldering 101: for the Beginner
I will talk about the basics of SMD soldering. I will be talking about soldering with hot air not with a soldering iron. I have seen and done some SMD soldering with a soldering iron but hot air is easier.
Things you will need:
Hot air gun with a controllable temperature.(I have a Aoyue 866)
Infrared thermometer (optional).
Step 1: Know Your Parts.
SMD components can be very sensitive to heat. You can always check the datasheet before starting if you are worrying about damaging a IC.
I have seen a few IC where they can only handle a temp a few degrees above the melting point of solder. Most solder melts about 370F (188C). Just keep that in mind if you are new to SMD work.
Step 2: Getting Started
You want to heat the board fairly even as everything expanse and contracts with heat and cold.
NOTE: most hot air stations use Celsius not Fahrenheit.
Some stations has a built in perheater. This heats the bottom of the PCB. Its a good Idea to set the temp below 370F (188C) I set mine about 150C
If you have a non-contact infrared thermometer measure the temp of the bottom of the PCB. Do not touch or move the board! once your PCB is around the set temp you can move on.
Now turn your hot air on and set your temp to 370F (188C).
Once your hot air has reached your set temp you can position the hot air gun over the IC. Leaving a small gap between the IC and the gun.
DO NOT TOUCH THE PCB AND OR MOVE THE PCB!!! You could cause parts to move or fall off. It would be a night mare.
Using your infrared thermometer you can tell the temp of the board by removing the hot air gun and testing the board. Once your PCB is 370F (188C) you can try and remove the IC. Be careful to pull straight up and be genital you do not want to cause and vibration on the board. This may cause a bad connection somewhere else or a short.
If it doesn't come easy apply more heat a want a few more minutes.
Once you removed your component let your board cool down. The longer your PCB is hot more better chance you will damage something. The longer your board takes to cool the stronger the connections will be.
Once you can handle the PCB clean the connections with your soldering iron and apply more solder and some flux
Place the board back on the preheater.
Place the IC back where it came from. Make sure its the same way! Make sure the connections are lined up.
Now you can reheat your board the same way as above.
Once you board is fully heated you should be able to see the solder run up the connections of the IC.
Now let you board cool again.
Once you board is fully cooled down to room temp you can test you PCB out to make sure it working.
Good luck I hope I could help you.
We have a be nice policy.
Please be positive and constructive.