Specifications for Handling Defective PCB Assembly You Should Know

In the process of PCB assembly and processing, unqualified PCBA are usually found during the manufacturing, assembly or testing process, one or more of which do not meet the requirements of drawings, design regulations, functional requirements, inspection standards or other specified technical documents.

1. Reasons for PCBA Unqualified

● Unqualified PCBA Production Process

PCB fabrication workers made mistakes during operation, such as incorrect component placement, incorrect soldering, incorrect temperature control, improper soldering process, incorrect patching, etc.ESD (electrostatic discharge) protection measures were not strictly implemented during the production process, damaging sensitive components. At the same time, the solder, flux or PCB substrate used was defective or did not meet the specifications, or the reflow oven, automatic patch machine, etc. failed or was improperly debugged.

● Unqualified Data Leads to Unqualified PCBA

Errors in design data such as PCB design schematics, BOM (bill of materials), Gerber files, etc. lead to problems in the manufacturing or assembly process. Incomplete or unclear PCB design drawings or specifications lead to misunderstandings in production.

● Defective Products Caused by Outsourcing

The production quality of outsourcing factories is unstable, and there are problems in management, such as lax process control and insufficient quality inspection.  After outsourcing processing the printed circuit board finished product assembly is damaged during transportation, such as physical or static damage, resulting in the processed PCBA not meeting quality requirements.

● Defective Products Found During Delivery or Use

Functional testing, environmental testing or aging testing before product delivery is not comprehensive enough to find potential problems in time. The actual use environment or conditions were not fully considered during the design phase, resulting in problems with the product during use. After a period of use, the product becomes defective due to the natural aging of components or the gradual exposure of hidden defects.

2. Hazards of Improper Handling of Unqualified Circuit Board

● Reduced PCBA Reliability

Unqualified circuit boards cause functional failures in the product during use, leading to early failure, shortened product life, reduced reliability, and failure to meet design requirements. It may even cause safety issues such as overheating, short circuits, and fire risks, threatening user safety.

● PCBA Manufacturers’ Capacity Trust Crisis

Unqualified printed circuit boards flow into the market. If customers encounter problems during use, it will trigger many complaints and returns, affecting customer satisfaction, reducing customer trust in the brand, and causing damage to the brand’s reputation and loss of market share.

● Economic Losses

Improper handling of unqualified boards may require rework or on-site repairs, increasing production and service costs and significant economic losses.

Unused PCB manufacturing from the same batch may accumulate into scrap, increasing inventory management costs and material waste.

● Impact on PCBA Quality Certification

Improper handling of unqualified PCBA will expose the defects in the company’s quality management system, affect the overall quality control level and ISO and other certifications, and have adverse consequences on all aspects of the company.

3. Circuit Board Non-conforming Treatment Specifications

● Handling of Unqualified PCB Assembly When The Product is Delivered or Used

When the PCBA board has been delivered and quality problems are found, the Quality Inspection Department will immediately issue an “Unqualified Product Report” to the Sales Department to notify the customer to return the product. After the product is returned, the Quality Inspection Department QA will provide the model, quantity and order batch information to the finished product warehouse. The finished product warehouse is responsible for returning the order to the factory final inspection process, and the Quality Inspection Department QA will follow up to evaluate the repair, rework or scrapping.

● Unqualified PCBA Found During Manufacturing

When unqualified PCBA are found during production, quality inspection or use, they should be marked immediately and recorded in detail. The records include the reasons for the incompetent, the time of discovery, the responsible personnel, etc. Separate the unqualified PCB assembly from qualified products and store them in the designated unqualified product area to avoid their misuse or mixing into the production flow.

● Analysis of Reasons for Non-conformity

The circuit board assembly production team should conduct a preliminary analysis of non-conforming products to identify possible causes, such as materials, processes, equipment, operations, etc. The analysis process and results should be recorded in the non-conformity report to ensure the integrity and traceability of the information.

● Improve the Process

After a comprehensive analysis of unqualified PCBA, the results are obtained, and the production process, equipment parameters, or operating procedures are modified to ensure that similar problems will not occur again.

Carry out targeted training for PCBA-related operators to improve the ability to identify and prevent unqualified products during production and testing. Track and confirm the PCBA manufacturing and production to ensure its effectiveness and conduct regular reviews.

Regularly review the handling of unqualified products, analyze trends, identify potential problems, and continuously improve the quality management system. For recurring or major unqualified problems, launch special quality improvement projects to ensure that the problems are completely resolved.