Why do PCBA circuit boards sometimes require a dispensing process?

Often, customers ask the PCBA factory if our products require a dispensing process during PCBA processing? At this point, we will communicate with the customer and determine whether to use the dispensing process based on the actual usage scenarios of the product in the future. Below, we will explain in detail what is the dispensing process and when it is necessary to do it.

1. What is the dispensing process?

We search for dispensing technology and can see an explanation about dispensing technology on Baidu Baike: dispensing is a process, also known as gluing, coating, pouring, dripping, etc. It involves applying, sealing, and dripping electronic glue, oil, or other liquids onto a product to make it adhere, seal, insulate, fix, and have a smooth surface. According to the explanation provided by Baidu Baike, we can understand that the dispensing process is actually a process for protecting products.

2. Why do we need to do the dispensing process?

The dispensing process has two main functions: preventing loosening of solder joints and moisture-proof insulation. Most places that require dispensing technology are located in areas with weak structures on the PCB, such as chips. When the product experiences a drop vibration, the PCB will oscillate back and forth, and the vibration will be transmitted to the solder joint position between the chip and the PCB, causing the solder joint to crack. At this point, dispensing glue does indeed completely surround the solder joint, reducing the risk of cracking of the solder joint itself. Of course, not all PCBAs will use the dispensing process, as its existence also brings some drawbacks, such as the complexity of the production process and the increased difficulty of disassembly and repair (if the chip is stuck and difficult to remove, it needs to be removed first)

Objectively speaking, dispensing glue can improve the reliability of the product, which is responsible to the user. Not dispensing glue can reduce costs, which is responsible to oneself. At the process level, dispensing glue is not a necessary option, and it can be omitted for cost considerations. However, it is a good practice to improve product reliability and avoid quality hazards, and should be done out of responsibility to the user. Whether to apply glue or not depends on the actual usage of the product.