Household Appliance 8L Gold Finger 5U Immersion Gold 370hr Fr 4 High Tg PCB

Multilayer PCB Specification:

What’s the meaning of gold finger in PCB board?

The connecting gold finger is the connection between the memory module and the memory slot, and all signals are transmitted through the golden finger. The gold finger is composed of a plurality of golden conductive contacts. Because the surface is gold-plated and the conductive contacts are arranged like a finger, it is called a "golden finger". The gold finger is actually coated with a layer of gold on a copper clad plate by a special process because gold is highly resistant to oxidation and has high conductivity. However, because of the high price of gold, more memory is currently replaced by tin plating. Since the 1990s, tin materials have become popular. At present, the "golden fingers" of motherboards, memory and graphics cards are almost always used. Tin material, only some of the high-performance server / workstation accessories contact points will continue to use gold-plated practices, the price is naturally high.

Gold Finger: (Gold Finger or Edge Connector) Insert one end of the PCB into the connector card slot, and use the connector pin as the external connection of the pcb board to make the pad or copper contact with the corresponding pin. To achieve the purpose of conduction, and plated nickel or gold on this pad or copper plate of pcb board, because it is a finger shape, it is called gold finger. The reason why gold is chosen is because of its superior conductivity and oxidation resistance. Sex. But because the cost of gold is extremely high, it is only used for local gold plating such as gold fingers.

High TG pcb Features:

Excellent heat dissipation, 3-4 times

better than normal FR-4

Excellent thermal and insulation reliability

Superior processability and low Z-CTE

A high TG (glass transition) PCB, also known as a high-temperature PCB, is a type of printed circuit board designed to withstand elevated temperatures.

The glass transition temperature refers to the temperature at which the resin material used in a PCB transitions from a solid, rigid state to a more flexible or rubbery state. Standard PCBs typically have a glass transition temperature of around 130-140°C. However, high TG PCBs are engineered to have a higher glass transition temperature, usually ranging from 150°C to 180°C or even higher.

The higher TG value of the PCB material allows it to withstand increased heat without undergoing significant dimensional changes or loss of mechanical integrity. This makes high TG PCBs suitable for applications that involve high-temperature environments, such as power electronics, automotive electronics, aerospace systems, and industrial equipment.

High TG PCBs are usually constructed using specialized laminates with thermally stable resin systems, such as FR-4 with a higher TG rating or other advanced materials like polyimide (PI) or ceramic-filled laminates. These materials exhibit better thermal stability, lower coefficient of thermal expansion (CTE), and improved mechanical strength compared to standard PCB materials.

The manufacturing process for high TG PCBs involves specific techniques to ensure proper bonding and adhesion of copper traces, vias, and other components to withstand the higher temperatures during assembly and operation. This may include using controlled heating and cooling profiles during lamination, improved copper plating techniques, and ensuring appropriate solder mask materials and processes.

Overall, high TG PCBs offer enhanced heat resistance and reliability, making them suitable for demanding applications where exposure to elevated temperatures is a concern.