How Much Heat Can PCB Absorb?
1. What is a high TG PCB material?
When the temperature of the printed circuit board rises to a certain area, the substrate will change from the "glass state" to the "rubber state", and the temperature at this time is called the glass transition temperature (Tg) of the board.
In other words, PCB high tg is the highest temperature (°C) at which the substrate maintains rigidity. That is to say, ordinary printed circuit board substrate materials not only produce softening, deformation, melting and other phenomena at high temperatures, but also exhibit a sharp decline in mechanical and electrical properties.
Generally, the tg in the PCB board is more than 130 degrees, the high Tg is generally greater than 170 degrees, and the medium Tg is about greater than 150 degrees. Usually the PCB circuit board with Tg≥170℃ is called high Tg PCB.
The Tg of the substrate is increased, and the characteristics of the heat resistance, moisture resistance, chemical resistance, and stability of the circuit board will be improved and improved. The higher the TG value, the better the temperature resistance of the plate, especially in the lead-free process production of PCBA, where high Tg applications are more common.
2. How much heat can the PCB absorb?
How much heat a PCB can withstand depends on the material it is made of. The material with the best thermal performance can provide reliable resistance to the effects of high temperature, while some materials have poor reliability at high temperatures. A measure called the glass transition temperature (TG) helps indicate this resistance. For example, the TG of FR-4 is about 135 degrees Celsius.
If a printed circuit board can withstand a temperature of 150 degrees Celsius, it is usually defined as a high temperature PCB. Some high-temperature PCBs may be able to withstand higher heat, but printed circuit boards made of materials with lower heat resistance will only be able to operate safely at much lower temperatures.
PCBA company's high-temperature PCBs are becoming more and more common in automotive and industrial applications where extreme temperatures are part of the working environment.