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How to Remove an SMD Transistor

Updated July 20, 2017

A transistor is an electronic component used extensively in all kinds of electronic circuits, such as televisions, cell phones and computers. Transistors are available in two types of packaging: through-hole or surface mount device, or SMD. A through-hole type transistor has leads for soldering. An SMD transistor, on the other hand, has terminals instead of leads for making connections. These terminals are soldered directly on the pads of the printed circuit board, or PCB. You can remove an SMD transistor from a PCB with the help of a soldering iron.

Turn the soldering iron on and set it at a temperature of 204 degrees Celsius.

Place the PCB on a flat, dry surface with the component side facing up.

Identify the SMD transistor to be removed from the board. The transistor will have three terminals soldered to the pads on the board. You have to desolder these terminals to remove the transistor.

Place the copper braid on any one of the terminals of the transistor and press it gently with the soldering iron tip. Within four to five seconds, the solder will melt and be absorbed by the copper braid. Wait until all the solder on the pad has been absorbed by the braid. Retract the braid and place the soldering iron tip back in its holder. Cut off the front part of the copper braid that has absorbed the solder, using a wire cutter. Repeat this process to desolder the other two terminals.

Lift the transistor off the board with the tweezers.

Warning

Work in a well-ventilated area while soldering, as the solder fumes may cause breathing problems and eye irritation. Keep the soldering iron tip away from your body to avoid skin burns.

Things You'll Need

  • PCB
  • Soldering iron
  • Copper braid
  • Wire cutter
  • Tweezers
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About the Author

Naeem Ahmed has been an established author of technical literature since 1989. He has numerous publications to his credit in peer-reviewed research journals such as "Physical Review Letters" and "Nuclear Instruments and Methods in Physics Research." With a Ph.D. in physics from Siegen University in Germany, he is an active researcher and academic.