PCBA and PCB

What Is the Difference Between PCBA and PCB?

Printed circuit board (PCB) and printed circuit board assembly (PCBA) are essential names in the electrical industry. Some people use them alternately, but they are two different things.

The main difference between the two terms is that the PCB refers to a blank circuit board, while the PCBA relates to a panel containing all the electronic components needed for the board to operate as required. The PCB is not yet operational because it does not have the necessary details, while the PCBA is a complete and functional board. PCBs and PCBAs are two different parts of the same process - the PCBA is built on top of an existing PCB.

This guide will look at PCB definitions, PCBA definitions, and the differences between the two terms.

What is PCB?

PCBs are the basis of modern electrical equipment. They mechanically support and connect electronic components electronically. The boards themselves are made of laminate materials, such as fibreglass or epoxy composite, and contain processed channels connecting different board parts. These methods are printed or labelled following the pre-determined design of the PCB.

Types of PCBs:

The main types of PCBs include:

  • Single-layer PCBs are the simplest type of PCBs and are covered with a single layer of operational material and a layer of commercially available masks. PCB components are marked with a silkscreen.
  • Double-layer PCBs have a range of conductors on both the top and bottom of the board, giving them more flexibility and smaller size than single-layer PCBs.
  • Multi-layer PCBs have more than two layers of operation and are used in complex systems.

Other standard PCBs include flexible PCBs, solid PCBs, and solid PCBs.

Materials Used:

The substrate material for PCBs is usually fibreglass, epoxy composite or other laminate material. Driving materials on one or both sides of the board are usually copper. The circuits printed, assembled, or attached to the substrate according to the design are copper circuits covered with tin-lead to prevent oxidation. PCBs have contact fingers on their outer edges, coated with tin-lead and other materials, such as nickel and gold, to increase efficiency.

Apps:

PCBs are used in various electrical applications, including consumer electronics, heavy machinery, robots, car parts and medical equipment.

Examples include:

  • Computers
  • Cell phones
  • TVs
  • Radios
  • Printers
  • Calculators
  • Electrical items
  • Lighting systems
  • Medical imaging systems
  • Pacemakers
  • Engine management systems
  • Industrial controls
  • Telecom towers
  • Data storage
  • Satellite systems

What is the Meaning of PCBA?

Although PCB refers to a blank board, PCBA is a finished PCB assembly that contains all the electronic components needed to make the board work as required. PCBA may also refer to the system for assembling the board with the needed components.

There are two main methods that a PCBA company can use in assembling a PCB:

1. Surface-Mount Technology:

Surface-mount (SMT) technology is a composite process that involves mounting electronic components on the surface of a PCB. It works automatically and is flexible, and allows for high-density connectivity. It will enable manufacturers to classify complex regions into smaller parts.

The four basic steps of PCBA SMT are:
  • Preparing the PCB: First, the connector places the solder paste where it is needed on the board.
  • Placing elements: Next, the composer puts the parts on the board, usually using a selection machine and location.
  • Reflow soldering: The connector then heats the boards in a recessed oven until the solder dough reaches the required temperature for the solder joints to form.
  • Testing: The composer performs testing throughout the SMT process, including pre-adhesive components and before and after re-solder.

2. Thru-Hole Technology:

Thru-hole technology is a coupling process that involves drilling holes into a PCB where electronic components called trackers can be connected. It is a technology older than SMT but makes stronger connections between the board and parts, making them more durable and reliable.

Thru-hole integration can be automatic or default. Procedures for the PCBA thru-hole process include:

  • Drilling holes: The first step in the thru-hole process involves drilling holes in the board. These holes should be the right size for the lead section.
  • Tracing: Next, the composer places the traces in the holes.
  • Soldering: The next step in this process is soldering. This step ensures that the parts are kept tight.
  • Evaluation: Throughout this process, the assembly is monitored to ensure that the PCBA will perform as expected.

How Are PCBA and PCB Related?

PCB and PCBA are the results of two different steps of the same process as a whole. The PCB is a blank circuit board with no electronic components attached, while the PCBA is a complete assembly containing all the details required for the board to operate as needed for the required application. The PCB is not yet operational, while the PCBA is ready for use in electrical equipment.

Producing a blank board is a more straightforward process than having a finished PCBA due to the various components and processes involved in assembling a PCB. It is also more expensive to produce PCBA than a blank PCB. However, both steps are required to create a completed board. You cannot make a PCBA without a PCB. PCB manufacturing is the first step in the process, and PCBA production builds on that first step.

Another difference is how PCBs and PCBAs are packaged. PCBs are usually packaged using vacuum packaging, while PCBAs require a compartmental or anti-static package.

By hqt001