What Testing Processes Are Integral to PCB Circuit Board Assembly?

Integral to PCB Circuit Board Assembly

When it comes to pcb circuit board assembly, there are multiple testing processes that are integral to the process. These tests can range from the very basic to the complex, and they are all designed to ensure that the finished product is as functional as possible.

The most important tests are those that check for design issues before the assembler starts working on the board. These types of tests include a silkscreen inspection to verify that the components are located in their proper place, a flying lead probing inspection for a complete electrical connection and a solderability test to see if the metal offers good wetting for a strong connection. The PCB also undergoes a burn-in test that pushes power through the electronics at their maximum-specified capacity to detect early failures and establish load capacity, which is particularly important for military or medical applications.

Another type of test that is often overlooked is the in-circuit testing (ICT) test, which checks the individual electronic components for their functionality and complies with industry standards like IPC 6012 and MIL-PRF-55110/31032. This test is the final phase of a functional circuit test and involves connecting an interface connector to the PCB and using a software program to stimulate the circuit and observe the results.

What Testing Processes Are Integral to PCB Circuit Board Assembly?

This is the most potent and effective form of PCB testing, ensuring that all of the components are in their correct locations and that they work correctly. It is a critical part of any quality-assurance program, and it can be used to detect short circuits, open circuits, resistance, capacitance and more. The ICT test requires a special testing fixture, which is custom-made to hold the PCB in place and ensure that the testing equipment makes reliable contact with each point on the board.

Other types of testing that are often used in conjunction with ICT are the Automated Optical Inspection (AOI) and the In-circuit Probe Test. AOI uses either 3D or 2D cameras to take pictures of the PCB and compare them to a detailed schematic. If the pictures do not match up to a certain degree, then the technician will flag the board for further inspection. AOI is an efficient and cost-effective option, but it cannot check for every aspect of the board, so it is usually paired with other testing methods.

Other testing procedures can include the micro-sectioning analysis, which is an in-depth inspection tool that examines the internal makeup of a PCB for flaws, opens and shorts. A time-domain reflectometer can also be utilized to find faults in transmission lines and coaxial cables, and a UV light can prevent oxidation of uncovered solder pads. Finally, a root cause analysis (RCA) can be helpful in identifying the source of an issue or failure. This is a data-driven approach to problem solving that can be useful in optimizing production and improving the overall quality of the products produced. Your ECM will be able to recommend the right testing methods for your specific production needs.