Any electronic project even if properly designed and built with utmost care is prone to bug and issues. It is very crucial to test the product or PCB thoroughly in early stages of design to ensure your projects going well. The testing can be done at PCB design level after using various design analysis techniques like EMI, Signal Integrity and Power Integrity ,the design issues can be minimized. But how do you test the PCB once bare- board PCB is in your hand or after components assembly has been done? How do you make sure that there are no shorts, open or bad solder joints? How to make sure current capacity, performance, component value and Impedance are within proper and expected tolerance level?
What are PCB Test Jigs
Also we should know and comprehend the common terms used in the Electronics hardware testing domain. Specialized and custom designed Test jigs and fixtures are used to test PCB. Test Point are identified and probed to identify the input to be given and output to be measured. A test jig can be identified as a device or machinery that holds a piece of machine work which now a days comprised of much electronic intelligence and guides the tools operating on it. It should not be confused with Test fixtures which are used to keep the object firmly in place. However, in PCB testing both the terms test jigs and test fixtures are interchangeably used as is meant as a electro-mechanical solution to test the printed circuit boards or PCB’s. Custom-made Test jigs and test fixtures are made as per the application of the board to test its test points.
The way of pcb testing
(1) Bare-board tests
Bare-board test are the tests done on unpopulated boards where defined circuit connection is verified properly on the fabricated board. A small voltage is applied and is verified at the appropriate points, a “short”, “open” are identified in these types of tests. Industrial CT scanning can show details of soldered path and connections by generating a 3D rendering of the board along with 2D image slices.
(2) Assembly Level Tests
After the board has been properly assembled it may be tested in a variety of ways using either manual inspection or using expensive Automatic test equipment (ATE).Automatic test equipment enables PCB test, and equipment test to be undertaken very swiftly. Automatic test equipment is quite expensive, and therefore it is necessary to select the proper type suitable for the application and board to be tested.
(3) Function tests
Functional test (FCT) is used as a final manufacturing step. It provides a pass/fail determination on finished PCBs before they are shipped. An FCT’s purpose in manufacturing is to validate that product hardware is free of defects that could, otherwise, adversely affect the product’s correct functioning in a system application.
In short, FCT verifies a PCB’s functionality and its behavior. It is important to emphasize that the requirements of a functional test, its development, and procedures vary widely from PCB to PCB and system to system.Functional testers typically interface to the PCB under test via its edge connector or a test-probe point. This testing simulates the final electrical environment in which the PCB will be used.The most common form of functional test, known as “hot mock-up” simply verifies that the PCB is functioning properly. More sophisticated functional tests involve cycling the PCB through an exhaustive range of operational tests.
Where to get your pcb project well done
PCBASTORE Supports a whole set of complete PCB test system (from initial circuit inspection to final function test) to keep your electronics projects going well.