How to Build Smd LED Circuits
- 1). Lay the PCB to be populated on a flat surface.
- 2). Turn on the soldering iron and set it at a temperature of about 450 degrees Celsius.
- 3). Identify the pads where the first SMD LED is to be soldered on the board. It does not matter from which component you start as you will have to solder all of them one by one. Exercise special care in identifying the correct polarity of the LED and how it should be oriented on the PCB. Consult LED's datasheet to determine its polarity.
- 4). Melt a small amount of solder on one of the pads where LED is to be soldered. You can do this by touching the pad with the tip of the soldering iron and the solder at the same time.
- 5). Place the SMD to be soldered on the PCB using tweezers and align its terminals with the corresponding pads on the board. Since you have melted some solder on one of the pads, the LED will be slightly tilted vertically.
- 6). Touch the pad with the solder with the tip of the soldering iron while pushing the LED down gently with the tweezers. Be careful as not to use too much force as it may displace the LED from its pads.
- 7). Take the soldering iron tip off of the pad as soon as the solder melts. It will immediately solidify and create connection between the pad and the LED terminal.
- 8). Touch briefly the interface of the other LED terminal and the corresponding pad with the tip of the soldering iron and solder at the same time. Take off the soldering iron tip and the solder as soon as you see that the solder has melted.
- 9). Repeat this process for all SMD components.
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