What are the benefits of AOI detection for PCBA?

 In the SMT patch processing process of the PCBA industry, the AOI detector is essential. It is a new piece of equipment that has only become popular in recent years. It can automatically inspect, automatically alarm, show anomalies, and fully automate. AOI detection can better detect problems with problems to ensure product quality. Next, I will introduce the principles and benefits of AOI detection.

AOI detection principle

Take SMT detection as an example. When automatically detected, the machine automatically scans the PCB through the camera, collects images, and compares the tested solder joints with the qualified parameters in the database. After image processing, the sign displayed/marked the defect for repair.

Of course, AOI detection can be used not only for SMT detection, but also for the following processes:

1. After printing tin paste, it mainly checks the printing of welded paste;

2. After the SMT stickers are placed, check the correctness of the patch, you can find errors earlier to reduce costs;

3. After the chip is installed, the detection system can check the chip polarity errors on PCB missing, offset, skewed chips;

4. After the return welding, at the end of the production line. The system can detect missing components, offset and skew, and component polar defects.

Advantages of AOI detection

1、positioning accuracy

With the reduction of component size in SMT production, the positioning accuracy of production and detection tools becomes more and more important. The AOI PCBA system must have sub-pixel accuracy to ensure that the system can locate the small position deviation of the 01005 defect and problem.

2、cut costs

Passing the PCBA AOI test in the SMT processing plant can increase PCB pass rates and ultimately reduce costs.

3、Multiple inspection goals

The AOI test is effective for PCB and circuit board assembly. In terms of PCB, it checks the defects, including short circuit, opening, and lack of solder. However, it checks several PCB assembly contents, such as component welding, value, and polarity.

4、Programmable lighting

In the SMT plant, it is crucial for all machine vision applications to achieve the right results. Given the dynamic characteristics of electronic products, it is difficult to find a single light source that can identify all faults. In order to ensure that components and PCB layouts have the widest fault coverage, dynamic light becomes crucial. The PCBA AOI test can set the extremely adjustable light array in its detection software due to the reduced cost of the luminous diode.

In addition, the AOI test can dynamically increase the contrast of the image, so that various faults can be easily found from different angles. Lighting programming is a key technology to ensure maximum detection range.

5、Network software

Data collection and search are an important part of any AOI PCBA system. The information can be mixed in writing, image sets, databases, or other formats. The basic purpose of most AOI PCBA systems is to collect data, but retrieving data is usually more difficult and depends on the setup of the production line.

6、Outstanding flexibility

AOI PCBA is suitable for all stages of the SMT patch manufacturing process. Because most errors are the result of the welding process failure, the AOI test after soldering can reduce the relevant costs and improve detection efficiency. In addition, it may immediately change the manufacturing or assembly settings to properly manufacture the following products.

What types of defects can be detected during PCBA AOI testing?

SMT production and processing Surface defects (including nodules and scratches), size defects (including opening, thinning and short circuit), incorrect component, component loss, and improper element arrangement can be detected by AOI.

Component offset, component polarity, lack of components or presence, crooked component, component flip, regional defects, insufficient welding paste around the lead, lack of filling testing, lead raising, welded balm alignment, and severe damage Components are problems that may have PCBAs with components.