Improved PCB Assembly Using Auto Optical Inspection

“In the past, checking whether all components are placed in correct solder pads is a manual inspection process. But with PCB boards containing hundreds of components, locating every component by eye and comparing it to the customer’s BOM (Bill of Materials) is extremely time consuming, tedious and prone to error. Automating this process using vision technology allows us to check the presence, positioning and identify of SMT components by directly reference the BOM and makes a huge difference, both in terms of time saving and accuracy. It is an essential requirement in Season Multilayer’ SMT house and Quality Department and as the check is done before reflow, the inspection is non-destructive thereby increasing the departmental efficiency and 1^st time pass rate.”

All Electronics PCB assemblies made by Season Multilayer are checked by AOI (Auto Optical Inspection). Positioning the right components in the right place is vital for SMT PCB assembly. As one of the printed circuit board assembly companies in Shenzhen, we are using the most recent camera technology to automate the PCB inspection process.

A versatile software interface, high frame rates, high resolution and future proof connectivity through USB were the reasons why we selected this camera for outgoing inspection for SMT assembly electronics. With this equipment, we improved the work efficiency and qualified PCBA accuracy rate.

In the surface mount technology (SMT) PCB assembly process, AOI is the vital process before X-ray inspection. This initial step allows a final check and helps to ensure that the correct component is positioned correctly on the board before board is sent for soldering. Season Multilayer ensures that the expected output conforms to the customer’s qualified process during standard PCBA production.

Season Multilayer, with its 4 independent surface mount lines, provides a flexible manufacturing facility capable of supporting larger regular production needs and a rapid PCBA prototype service. It is generally possible to accommodate any combination of through-hole (PTH) and surface mount (SMT) components:

Printed Circuit Boards (PCBs) for inspection are populated with the components positioned in the correct location on the board using solder paste. The AOI system is incorporated with a number of features, enabling operators to rapidly load customer BOMs, which comprises of the list of parts or components used and the placement on the PCB as indicated by the customer. The camera is automatically pushed to the exact location for inspection as each component is called up on the BOM, and it reaches solder paste at a resolution capable of imaging even 0201 components with a zoom function for higher magnification.