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What is FR4 Tg PCB?

As electronic technology continues to develop, there is a high demand for high Tg boards.Furthermore, glass transition temperature (Tg) is a very important property of an epoxy. Also, this temperature region is one whereby the base material, which is either glass or polymer changes from its glassy, rigid, solid state into a rubbery state.

All PCB features a unique Tg value which is usually based on the substrate. Furthermore, PCB will begin to alter its state. This affects the PCB fabrication process wrongly if the PCB’s operating temperature surpasses its Tg value. In addition, the PCB boards with high Tg usually feature better stability whenever there are high temperatures. This is due to the fact that the substrate offers better chemical and mechanical stability, and heat resistance for the board.

Therefore, your Tg value must fall within 20 and 25 degrees centigrade more compared to the operating temperature of that device expected for the board to be useful in selecting a PCB.

What Does FR4 Mean?

Printed circuit boards usually make use of composite material glass fabric as well as a flame retardant made of epoxy resin.

This reinforcing material of 4th grade is useful in PCB boards to help in resisting a more glass transition temperature. Also, the presence of this substrate in the PCB is significant, such as printed circuit boards (PCBs) present in the electrical machines.

FR means fire retardant material. Majority of PCB manufacturers make use of FR4 as a result of its consistent mechanical and physical properties. In addition, the FR4 laminates are board materials with epoxy pigment useful in enhancing the integrity of the circuit board.

What does High TG PCB Mean?

Base material, either glass or polymer, is shifting from its rigid, solid, glassy state to a rubbery state whereby the temperature rises to a specific area. The temperature here is referred to as the glass transition temperature(Tg). What we mean is that Tg is known as a mechanical property, which designates the glass transition temperature. This temperature is one at which this substrate stays rigid.

What are the Properties of the Fr4 Tg PCB?


The use of materials of high Tg PCB is becoming higher in the global electronics industry. The usefulness of these high Tg PCBs can be seen in communication equipment, control panels, and computers.

The major difference here is the high prices. This is because these high Tg fr4 PCBs are more expensive than the usual Tg PCBs. Furthermore, these high Tg material feature most of the important properties. These include:

  • Adhesion
  • Better strength and mechanical property
  • Stronger moisture resistance and water absorption
  • Stability in its dimensions
  • Thermal decomposition during any hot condition
  • Chemical resistance
  • High heat resistance or higher heat resistance
  • More resistance to any thermal stress
  • Longer durability for the PCB laminates
  • Reliable and efficient PTH
  • Lower CTE (coefficient of thermal expansion) at the Z-axis

What are the Benefits of a High Tg PCBs?

Greater stability: This automatically improves the chemical resistance, heat resistance, moisture resistance, temperature resistance and the device’s stability by raising the temperature of glass transition (Tg) of a specific PCB substrate.

It bears designs with high power density: A high Tg PCB serves as a very good solution for all heat management. This holds if that device features high power density as well as a high heat generation rate.

Also, with the use of the larger PCB (printed circuit board) in changing a device’s power and design requirements when reducing an ordinary board’s heat generation. In addition, it can also make use of high Tg PCB (Printed circuit board).

Great for HDI and multilayer PCBs: This can cause high heat dissipation levels. This is due to the fact that the HDI and multilayer PCBs feature dense circuits and are usually more compact. Therefore, the high Tg PCBs are usually useful for the HDI and multilayer PCBs. This ensures reliability during PCB fabrication

Reasons why Using the high Tg PCB is Necessary

Note that if yourPCB (printed circuit board) can’t bear the thermal load that is not having a Tg value that is 25 degrees centigrade less than the usual Tg, then there is a need for a high Tg PCB (Printed circuit board)to work with your applications.

Furthermore, it ensures the safety with your high Tg PCB if the product operates at a range of 130 degrees centigrade or more. The major reason behind the high Tg PCB is due to the movement onto the RoHS PCB (Printed circuit board). Therefore, there are additional PCB industries that are moving toward the high TG materials because the lead-free solder needed to flow will require higher temperatures.

What are the Applications of High Tg FR4?

Note that when a higher power density is present in electronic products and then heat generation also tends to disturb the heat sink as well as other parts of your products, the most appropriate solution is to using a high Tg FR4 PCB.

Furthermore, you’ll learn that the high Tg FR4 PCBs are usually applied in the electronic industries. These industries can function in high temperatures This is because high Tg FR4 PCB are becoming more popular recently. Top manufacturers like RayMing serve their customers from many different industries. They achieve this by offering high Tg FR4 PCBs having a heat resistance, which meet all the demands as well as the specifications of the customer in the quick lead time.

The following areas are places where the High Tg fr4 is applicable:


When designing, one important feature to look into when identifying PCBs is the high Tg. Furthermore, it is necessary to pick the material with respect to the usage. This refers to the low working or high temperature requirements. Other things to consider include the thermal expansion, electrical properties, temperature resistance, mechanical and electrical properties, high temperatures, and higher heat resistance or high heat resistance. Any questions? Please notify us.