10 Layer ENIG FR4 Tg150 PCB

The main advantage of high Tg materials is higher operating temperature (MOT), which can carry more current. According to experience, TG minus about 20 ℃ can be used as mot. At this temperature, the PCB can run normally for a long time without damage.

The heat resistance temperature of the common solder mask is usually lower than the Tg of the substrate. The conventional maximum operating temperature of solder mask is about 150 ℃. For high Tg applications beyond this temperature, it is recommended to select PCB without any solder mask or apply special high temperature resistant coating after assembly. If the standard conventional solder mask is used in high temperature environment, the solder mask will turn gray brown.