Your Trusted Electronic
Manufacturing Services Partner
0769-33381888
Your Trusted Electronic
Manufacturing Services Partner
0769-33381888
Release date: 2022-03-21
PCBA stands for Printed Circuit Board Assembly and refers to a circuit board assembled with electronic components such as diodes, transmitters, capacitors, resistors, and ICs with SMT and soldering assembly techniques. All electronic devices have PCBA, nowhere for electronic devices No. They range from smartphones to microwaves to laptops to cars.
It is a technique for mounting electronic components directly on the surface of a PCB. SMT is suitable for assembling tiny sensitive components such as transistors onto a circuit board. This technique helps to save more space as no drilling is required and also facilitates speeding up Production progress. Also, by applying surface mount technology, electronic components can be tightly assembled on the surface, so both sides of the PCB can be used.
Another method is through-hole technology, which was used earlier than SMT. THT is a technology that inserts electronic components into the circuit board through holes, and the manufacturer needs to solder the excess part of the wire on the board. More than SMT More time, but it still has some advantages. For example, by using through-hole technology, the electronic components are firmly bonded to the circuit board. So, this technology is suitable for large electronic components such as coils and capacitors, which can withstand high power, high voltage, and mechanical stress.
Let us understand the PCBA manufacturing process in detail:
First and foremost, the PCBA company applies the solder paste to the printed circuit board. During this process, you need to place the solder paste on some part of the board. That part contains different components.
Solder paste is made up of different tiny metal balls. And, the most commonly used substance in solder paste is tin i.e. 96.5%. The other substances of solder paste are silver and copper at 3% and 0.5% quantity respectively.
Manufacturers mix paste with flux. Because flux is a chemical that helps the solder melt and bond to the surface of the board. You must apply the solder paste in the right place and in the right amount. Manufacturers use different The applicator applies the paste at the intended location.
After successfully completing the first step, the pick and place machine must complete the next job. During this process, the manufacturer places different electronic components and SMDs on the circuit board. Today, the SMD is responsible for the non-connector components of the circuit board. You Will learn how to solder these SMDs to the board in the next steps.
You can use traditional methods or automated methods to pick up electronic components and place them on the board. In the traditional method, the manufacturer uses a pair of tweezers to place the components on the board. In contrast, the machine places the components on the board in an automated method. correct location.
After placing the components in the correct location, the manufacturer cures the solder paste. They can do this through a "reflow" process. In this process, the production team sends the board to a conveyor belt.
The conveyor belt has to go through a large reflow oven. And, a reflow oven is almost similar to a pizza oven. The oven contains several heaters at different temperatures. The heaters then heat the boards at different temperatures to 250o C. This temperature converts the solder into solder paste.
Similar to a heater, a conveyor belt then runs through a series of coolers. The coolers solidify the paste in a controlled manner. After this process, all electronic components are securely placed on the board.
After installing the components during the reflow process, you need to inspect the board for defects. During this process, the manufacturer also tests the functionality of the board. During the reflow process, many boards have bad connections or shorts. A lot of connectivity issues can happen in the previous step.
Therefore, there are various ways to check for misalignment and errors of a circuit board. Here are some excellent test methods:
Even in the era of automated manufacturing and testing, manual inspection is still very important. However, manual inspection is most effective for small-scale PCBA PCBAs. So, for large-scale PCBA boards, this inspection method becomes more inaccurate and impractical.
Except, observe the miner component for a long timeCan cause irritation and visual fatigue. This may result in inaccurate examinations.
For high-volume PCB PCBA, this method is one of the best options for testing. In this way, one AOI machine inspects the PCB using a large number of high-power cameras.
These cameras cover all angles to inspect different solder connections. AOI machines identify the strength of connections by the reflected light of solder connections. AOI machines can test hundreds of boards in a few hours.
This is another method used for board testing. This method is less common but more effective for complex or layered boards. X-rays can help manufacturers check for underlying problems.
Using the above method, if there is a problem, the manufacturing team either sends it back for rework or scrap.
If the inspection finds no errors, the next step is to check its operability. This means that the tester will check that it meets the requirements. Therefore, the board may need calibration to test its functionality.
Electronic components vary from board to board, depending on the type of PCBA. For example, these boards may have different types of PTH components.
<p class="nitro-offscreen" style="box-sizing: border-box; border: 0px; font-size: 18px; margin-top: 0px; margin-bottom: 0.97em; outline: 0px; padding: 0px ; vertical-align: baseline; overflow-wrap: break-word; color: rgb(21, 21, 21); font-family: "Cera Pro", sans-serif; white-space: normal; background-color: rgb(255, 255, 255);"> Plated through holes are different types of holes on a circuit board. By using these holes, components on a circuit board pass signals to or from different layers. PTH components require a special type of soldering method instead of just using solder paste.The process is very simple and straightforward. At one station, a person can easily insert a component into the appropriate PTH. Then, the person will pass the board to the next station. There will be many stations. At each station, a person will Insert a new component.
The loop continues until all components are installed. Therefore, this process can be long, depending on the number of PTH components.
This is an automated method of soldering. However, the soldering process in this technique is completely different. In this method, the boards are placed on a conveyor belt and then passed through an oven. The oven is filled with molten solder. And, the molten solder cleans the circuit board. However, this type of soldering is almost infeasible for double-sided boards.
After the soldering process is complete, the PCBA passes the final inspection. At any stage, the manufacturer can go through the board from the previous steps to mount other parts.
Functional testing is the most common term used for final inspection. In this step, the tester adjusts the board at his own pace. Except, the tester tests the board in the same environment where the circuit can work.
For example, testersTest the board at different voltages, signals, and currents. If the board fluctuates or behaves badly, the board fails the test. So the manufacturer can recycle or scratch the board.