What is the TG value of PCB and how to choose?

It is well known that the base material polymer or glass) is changing from a glassy, solid, rigid state to a rubbery state when the temperature rises to a certain region, so the temperature at this point is called the glass transition temperature (Tg). In other words, Tg is the mechanical property that specifies the glass transition temperature, i.e., the maximum temperature at which the glass remains rigid.

TG in PCB boards means temperature resistance. the higher the Tg point, the higher the temperature requirement when pressing the board, the harder and more brittle the board will be, which will affect the quality of the mechanically drilled holes to a certain extent in the subsequent process.

PCB board TG value classification

Common board TG value can be roughly divided into three major categories:

TG130: general TG value of the board, temperature resistance of about 140 ℃, common such TG value of the board is Sheng Yi S1141 and Kingboard KB-6164F

TG150: Medium TG value plate, temperature resistance 150℃~170℃, common such TG value plate is SangYi S1141 150 and Kingboard KB-6165F.

TG170: Higher TG value boards, temperature resistance above 170℃, common such TG value boards are SangYi S1170 and Kingboard KB-6167F, the cost of higher TG value boards is also relatively high.

How to choose pcb with different TG values?

PCBs with different TG (glass transition temperature) have their own advantages and application scenarios, which one is the best to choose depends on the specific application needs. The following are some common TG PCBs and their characteristics.
1.FR-4(TG 130°C-180°C):FR-4 is one of the most common and widely used TG PCB circuit board materials. It has good mechanical strength, electrical properties and heat resistance.FR-4 is suitable for most general applications of electronic equipment and is relatively low cost.

2. High TG PCB ( TG 150°C-200°C):High TG PCBs have a higher glass transition temperature than regular FR-4, providing better stability and reliability in high temperature environments. They are suitable for applications that require operation in high temperature environments, such as automotive electronics, industrial controls and aerospace.

3. High Frequency TG PCBs: High Frequency TG PCBs are designed for high frequency signal transmission with excellent impedance control and signal integrity. These boards are typically made of low dielectric constant and low loss materials to ensure optimal signal transmission.

4. Metal Substrates:Metal Substrates are a special type of TG PCB that has a layer of metal (usually aluminum or copper) covering the substrate for heat dissipation and conductivity. Metal substrates are suitable for high power applications, LED lighting and power electronics where good thermal performance is required.

The best choice of TG PCB depends on your application needs, such as operating environment, signal requirements, temperature requirements, cost constraints, etc.