The printed circuit board known as PCBs are used in electronic devices. The device is controlled by PCB. As the PCB is the brain of an electronic device the performance and reliability directly depend on PCB. In modern times the size of the electronic devices is decreased and hence the size of PCBs become smaller and complexity is increased.
As we all know while making the PCB it passes through different manufacturing stages. If there is a problem in one of the stages the performance of PCB is not at the mark. The quality control contains some of the basic measurements like the design of PCB, PCB manufacturing and PCB inspection.
PCB design has to be valid. It is the duty of project leader to ensure the PCB design file.
First, check the base material. After that print and etch each layer. In this step clear the unwanted etch resist and check properly that the unwanted copper etched away. In the end, make sure that the etch resist is not on the board.
After that check the inner layer copper and compare with design data. Next step is to check the diameter of the drilling holes.
The employee measures the copper thickness in the holes. After applying the solder mask the employee checks it using a microscope to ensure that every panel is aligned and no solder-mask traces. The thickness is measured using an X-ray scope.
Other Way to check PCB quality
One of them is inspected the PCB with naked eyes. This method is used for primary manufacturers who make low numbers of PCBs.
Other is using Microscope. The employees use tools like a magnifying glass. For the better look, they also use USB microscope which generates the image on the large screen.
The PCB quality is also checked through in-circuit tests. One is the bed of nails and other is fixtureless. In the bed of nails process a small series of spring-loaded pogo pins that press into various points to measure the resistance. The fixtureless or also know as flying-probe testing that sends the machine-operated probes to PCB to check the test points at high speed.
The X-ray technique is the quite expensive technique to inspect the PCB. The PCB is inspected same like using a microscope.
The not preferring method but a very effective method use the saw. It can slice the PCB but after slicing we can able to inspect the inner layers of PCB.
The AOI (automated optical inspection) are available in cheap and commercial grade as well. In the cheap AOI systems uses cheap webcams connects with open source computer vision and compare the images with default ones to find the defect. On the other side, the commercial AOI uses powerful cameras and RBG LEDs to ensure the solder quality and connections.
In the functional testing method, the employee turns on the power and perform various tests on it.
The inspection camera is also one of the best options to ensure the quality check. These cameras produce high-resolution images on the computer screen to inspect every detail of PCB.
The India Circuit is very quality conscious. They never accept a small error in PCB. Even after producing a large number of PCBs and then find a fault they reject the PCBs. After correcting the fault and then again manufacture and ship to the client.
Here in India Circuit our designers and production engineers closely inspect the production of PCB and perform the quality test on different stages.
The India Circuit also ensure that every PCB comes from the facility is faultless and long-lasting.