Copyright © 2021-2022 SHENZHEN KINGFORD TECHNOLOGY CO.,LTD. All Rights Reserved
Printed Circuit Boards, shortened as PCBs, are one of the primary things in electronics. PCBs allow you to place multiple electronic components neatly, as it does not involve long soldering lines. With that said, the conductive layers of copper are responsible for connecting the electronic components. Moreover, you can develop a permanent circuit with PCBs, which otherwise is not possible on a breadboard.
Numerous PCB designing software allows you to create customized PCB boards. However, you must know that there are some specific PCB tests that you should conduct after designing it.
But not getting your PCB made by a professional PCB manufacturing company can make conducting those tests strenuous. Now, the question arises what those specific tests are? Well, this is what we will be covering today.
Below specified are some of the standard testing methods. Or procedures that help a PCB manufacturing company know their manufactured PCBs are in optimal working condition.
In-Circuit Testing or ICT is one of the most popular and effective testing methods in PCB/PCBA. This method lets manufacturers know if their developed PCBs have any design flaws. Moreover, the ICT test also helps PCB manufacturers analyze the board's proper working. And the electronic components embedded in it. ICT system involves a test system that is built using different instruments, such as:
PCB manufacturers can find between 85%-90% of faults with the ICT testing method. Due to this, the ICT testing method is considered one of the efficient PCB/PCBA testing methods. You must know that the In-Circuit testing method is done at the end when a PCB has been fully developed. And all the electronic components, according to their place in a PCB, are soldered.
Some of the common faults that testers in a PCB manufacturing company can find using the ICT testing method are:
ICT test system involves an instrument made using different instruments, as mentioned earlier. This instrument is fixed. You need to put the PCB inside it. Moreover, the instrument body also consists of multiple probes.
PCB testers place a PCB board concerning the probes inside the fixture. It is because each probe has a different testing function. And are needed to be connected to specific test points in a PCB board. Not connecting the board accordingly with the probes won't allow you to run tests on your PCB successfully.
In addition, probes are connected to fixture interface pins, and fixture interface pins are connected to module interface pins. Module interface pins are connected to the tester pin card, which is what detects faults.
When the fixture cover is lifted, and the board is placed, signals flow from the card to the board. And then from the board back to the tester pin card. A default software with the ICT testing instrument displays the status "Pass" when the board has no error. And "Fail" when there are errors in a PCB/PCBA.
Another PCB/PCBA test is the Flying Probe Test. This testing method is different from ICT testing. This test does not involve any fixture that housed the instrument. Instead, numerous probes are fixed on a framework (flying probe tester). The framework can move along the X, Y and Z axis.
With Flying Probe Test, PCB testers can run tests such as:
Moreover, with Flying Probe Test, PCB testers can also find:
First, PCB testers or manufacturers create a code uploaded to the flying probe tester. The code is an integral part of the test process, and without it, you cannot conduct the test. It is because how would the tester know what it should be testing. After uploading the code to the flying probe tester, a PCB/PCBA is tested. Flying Probe Tester will test whatever is written in your code.
This is another one of the standard testing methods in PCB/PCBA. With this test, PCB manufacturers can analyze whether the developed PCB is according to the standards. And is it working properly or not. A functional Circuit Test is usually done at the end of the manufacturing process, and after all, the final assembly is done.
The functional Circuit Testing method is somewhat similar to the ICT testing method. The testing method consists of an instrument (fixture) that gives you the pass or fail status.
The fixture can either contain probes just like those of ICT or can contain edge connectors. The status is based on the behavior of a PCB board. The instrument monitors how a PCB behaves, including any abnormality, and then gives the output. Functional Circuit Test also needs a set of different programs to test the behavior of a PCB.
Functional Testers connect with a PCB/PCBA through the connectors or probes and then monitor its behavior based on the program. If all the design specifications and working of electronic components pass the program, PCB is deemed healthy PCB.
As the name suggests, Automated Optical Testing involves testing your PCB means of image comparison through software. The software is the default software in this testing method and is one of the precise testing methods.
PCB testers take images of a manufacturer PCB utilizing a camera with high precision levels. Using a camera with high precision levels is an integral part of the process. Images are present in the software because the images are then compared with the reference.
If the quality of the images is not good, it can affect the test results. A proper comparison cannot be made, for example.
Some of the faults that can be determined by this method are:
JTAG is also known as the boundary scan method. It is a process that is used for debugging of ICs. In such devices, a cell for boundary scan is present. Data is then moved past within these cells when it is present in shift register mode.
It is also known as AXI and is often used for checkup reasons. It comes with two types of AXI that are 2D and 3D. Professionals often use it as it needs experienced workers.
This intense method for a large capacity is mainly used. It uses a high power for moving power through your electrical gadgets. It works for almost 2 days or more. If it somehow is not successful, results can be fatal as well.
Looking out for what types of standardized testing are in PCB/PCBA? Do not forget to refer to the mentioned details about it.