AMC3330: how to improve the pollution degree

Hi Takahashi-san

Pollution degree is typically set by the application environment. 

For example, end equipment's with high humidity, PCBs where a screw must be applied to secure the PCB during manufacturing (potentially leading to stray PCB particles) or dirty environments would affect the pollution degree level. 

Applying conformal coating would help to protect the PCB and isolation barrier from such concerns, thereby reducing the pollution level of the application. 

This parameter is most important when determining the necessary creepage and clearance distances across the isolation barrier. Since applying conformal coating is sometimes undesirable, another solution would be to use devices with a larger creepage and clearance such as AMC1400 or AMC1411.