Printed Circuit Board Assembly (PCBA) – Process, Technology, Tips and Techniques

Printed circuit board assembly, also known as PCBA, is the process of soldering or assembly of electronic components to a PCB or printed circuit board. A circuit board prior to assembly of electronic components is known as PCB. Once electronic components are soldered, the board is called Printed Circuit Assembly (PCA) or Printed Circuit Board Assembly (PCBA).

It has to be noted that assembly of a circuit board is different from manufacturing a circuit board. Manufacturing printed circuit boards involve several processes including PCB designing and creating PCB prototype. Once a PCB is ready, electronic components need to be soldered onto it before it can be used in any electronic equipment or gadget. This assembly of electronic components depends on type of circuit board, type of electronic components and purpose of the circuit board.

Things Needed for Printed Circuit Board Assembly

Following electronics parts and consumables are needed for PCB assembly –

  1. Printed Circuit Board
  2. Electronic components
  3. Soldering materials including solder wire, solder paste, solder bar, solder preforms (depending on the type of soldering to be done)
  4. Soldering flux
  5. Soldering equipments including soldering station, wave soldering machine, SMT equipment, inspection and testing equipment etc.

Once all of the above equipment, electronic parts and all raw materials are arranged, it is time to start the assembly process.

Printed Circuit Board Assembly with Thru-Hole Electronic Components

Printed Circuit Board Assembly

Printed Circuit Board Assembly

Electronic components that have leads coming out and are inserted through tiny holes in the PCB for soldering are called thru-hole electronic components. The assembly or soldering process for these components include wave soldering and hand soldering – Wave Soldering – A PCB assembly process in which solder in the form of solder bar are put in a high-temperature bath. This solder remains in the bath in molten form and forms a wave at very high temperature. The range of temperature depends on the type of solder. Traditional tin / lead (Sn/Pb) solder has lower melting point than lead-free (Pb-Free) solder. The PCB with all the thru-hole electronic components in holes is passed over molted solder with a help of a conveyor belt. The whole wave soldering process includes following steps:

  1. Inserting of electronic components
  2. Flux application
  3. Preheat
  4. Cleaning
  5. Testing

Once the wave soldering is done, the PCBA is cleaned and tested. If any fault or solder joint is found, it is sent for rework, which is generally done by hand. Hand Soldering – Hand soldering is done in manufacturing units with less work load or in rework / repair jobs. A good quality soldering station or soldering iron and solder wire and flux are used in the process.

Surface Mount Technology (SMT)

Surface Mount Technology or SMT is a PCB assembly process for SMD electronic components. SMD components don’t have leads or legs. They are mounted on the surface of the circuit board. The equipments, electronic components and other soldering material used in this assembly process is different from thru-hole soldering process.

More Information of Printed Circuit Board Assembly

For more information of PCB assembly process and other guidelines, please visit following websites:

Read More:

PCB Design guidelines

PCB Standards and specifications

  • MIL-PRF-31032, Performance Specification Printed Circuit Board/Printed Wiring Board
  • MIL-PRF-55110, Performance Specification for Rigid Printed Circuit Board/Printed Wiring Board
  • MIL-PRF-50884, Performance Specification for Flexible and Rigid-Flexible Printed Circuit Board/Printed Wiring Board
  • GR-1274, Requirements for Reliability Qualification Testing of Printed Wiring Assemblies

PCB Do-it-yourself (DIY) guides

PCB Others

9 Responses to Printed Circuit Board Assembly (PCBA) – Process, Technology, Tips and Techniques

  1. […] components, both active and passive, are lifeline of any printed circuit assembly. They both play vital roles in the functioning of any electronic device. Electronic Components are […]

  2. […] on the circuit board and getting it ready for use is what is called circuit board assembly. A Circuit board assembly process may use through-hole assembly technology or surface mount technology (SMT) or a mix to both. Once […]

  3. […] PCB before soldering electronic components onto the board. The main function of using flux in any circuit board assembly or rework is to clean and remove any oxide from the board prior to soldering. Solder flux helps to […]

  4. […] flux is a kind of chemical used in PCB soldering and assembly. It is basically used to clean surface of PCB before soldering process. The main function of flux […]

  5. […] the circuit board: Prior to assembly of electronic components on to the board, it needs to be tested. This testing can be done using nails tester, flying probe tester are other […]

  6. […] station unit. Most soldering stations have temperature control and are mostly used in electronics PCB assembly and manufacturing units. They are also used for mass repairing of circuit boards. Most genuine […]

  7. […] soldering irons, soldering and desoldering stations, hot air SMD rework systems and all other PCB assembly tools and […]

  8. […] Printed Circuit Board Assembly (PCBA) – Process, Technology, Tips and Techniques […]

  9. […] the electronics industry will remain in a mixed pcb assembly mode (Use of SMD Electronic Components and Through-Hole Electronic Components […]

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