Glossary of Terms

A BGA is a type of surface-mount packaging used for integrated circuits. It employs a different approach to the connections than those of more conventional surface-mount connections, such as a dual in-line or flat package. A BGA uses the underside of the package, where there is a considerable area for the connections, instead of just the perimeter. The traces that connect the package’s leads to the wires or balls are on average shorter than with a perimeter-only type of packaging, leading to better performance at high speeds.

A bench test is a critical evaluation carried out on a machine, a component, or software prior to installation or before it is released for use, to ensure that it works properly.

A box build is the process by which various PCBs are assembled together. A box build is also sometimes called “systems integration.” The process includes installing the PCBs then connecting all the components with various wire and cable into a complete system. The box build process is specific to each project and can include varying degrees of complexity at each step.

Printed circuit board assembly is the process of connecting the electronic components with the wirings of printed circuit boards. These components may include resistors, capacitors, integrated circuits (ICs), and others depending on the application of the electronic device. PCBs can have up to twelve layers depending on the complexity of the electronic devices involved. Printed circuit board assembly requires absolute precision to ensure the successful operation of the electronic devices.

Circuit design is the process of determining the physical form that an electronic circuit will take. The process can be applied to projects ranging from complex electronic systems all the way down to the individual transistors within an integrated circuit. Simple circuit designs can often be developed by one person without a structured design process, but more complex designs often require teams of designers following a systematic approach with intelligently guided computer simulation.

Conformal coating is a thin polymeric film that conforms to the contours of a printed circuit board to protect the board’s components against moisture, dust, chemicals, and temperature extremes.

A flying probe test system uses two to six probes that move or fly around the PCB to conduct its tests, allowing a user to test larger boards. The system is equipped with pogo-pin based probes that inject and monitor signals via test pins on the boards.

It tests for assembly problems due to solder connections, as well as the presence of components, their values, and polarities.

Functional testing is the last gatekeeper in the manufacturing process, deciding a board’s final pass/fail status. This comprehensive test determines whether everything works together and can communicate properly. Through a combination of connected cables, test probes, and test software, the functional test fixture simulates the board’s behavior based on the tester’s specifications.

An ICT uses multiple probes to make simultaneous contact with all of the test points on the PCB to electrically test its circuits for assembly failures, such as shorts or bad solder joints. It also checks critical component values and overall board functionality, and can be enhanced for more complex testing with other adapters and modules.

Modular assembly cells allow systems integrators to build a multi-station automated assembly system more quickly and efficiently, which can lower costs, increase flexibility and decrease build times. Modular assembly cells with a standardized layout and control system can be configured as standalone, automated workstations or can be linked together to create a fully automated assembly line. Cells can often be equipped with a variety of technologies, such as rotary-indexing dials, robots and vision systems. Quick-change technology enables assembly-specific machines to be swapped out efficiently.

A prototype is an early sample, model, or release of a product built to evaluate the design before a full production run. Prototypes generally offer fewer advanced options and lower production tolerances, but they can demonstrate whether a design meets performance and quality standards. Engineers use prototype PCBs early in the design process to test proof-of-concept of single functions. Multiple runs of prototypes are often used to test redesigns or retest a single function before moving on to a more complex design. Discovering elements that require correction earlier in the process can save costs.

QFN — quad-flat no-leads — is a surface-mount technology that connects integrated circuits to the surfaces of PCBs without through-holes. QFN packages typically use a copper lead frame for the die assembly and PCB interconnection. The QFN can have a single or multiple rows of pins. This package allows users to view and contact leads after assembly.

The soldering line is a precise and carefully controlled machine process of attaching components to the PCB board. The machine is a self-contained oven that takes a bare board with placed components on one end and provides a fully soldered board on the other end. As the board travels on the conveyor belt, it undergoes several processes, including flux application, preheating and the soldering wave.

This widely used PCB assembly process involves components with metal tabs that can be easily soldered to the PCBs. The technique offers higher circuit densities when the components are fixed at both sides of the PCBs with effective soldering methods.

Through-hole technology (also spelled “thru-hole”) is a mounting scheme that involves the use of leads on the components that are inserted into holes that go completely through the PCBs. They are then soldered to pads on the opposite side of the board, either by manual assembly or by the use of automated insertion mount machines. Through-hole soldering creates a strong bond between components and the PCB, which is advantageous for larger components that will undergo high power, high voltage, and mechanical stress.