The so-called gold fingers of the circuit board refer to a row of equidistantly arranged square pads with exposed copper and gold plating. It is mostly used for electrical connection pins connected to boards, LCD connections, motherboards, chassis, etc., because a thin layer of gold is plated on the nickel-plated copper foil.
一、Definition and function of gold finger on PCB circuit board:
Gold Finger: (GoldFinger or EdgeConnector) Insert one end of the PCB circuit board into the connector card slot, use the pins of the connector as the outlet for the external connection of the circuit board, and make the pad or copper contact with the pins at the corresponding position. To achieve the purpose of conduction, nickel gold is plated on the pad or copper skin of the PCB board because it is in the shape of a finger, so it is called a gold finger. The reason why gold is chosen is because of its superior conductivity, oxidation resistance and wear resistance. However, because the cost of gold is extremely high, it is only used for partial gold plating such as gold fingers.
二、Classification and identification characteristics of circuit board golden fingers
Gold finger classification of circuit boards:
1. Conventional golden finger (flush finger);
2. Segmented gold finger (intermittent gold finger);
3. Long and short gold fingers (that is, uneven gold fingers).
Gold finger circuit boards of different lengths
1. Conventional gold fingers (flush fingers; rectangular pads of the same length and width are neatly arranged at the edge of the board. The following picture shows: network cards, graphics cards and other types of physical objects, with more gold fingers. Some small boards have fewer gold fingers;
2. Segmented gold fingers (intermittent gold fingers): rectangular pads with different lengths located on the edge of the board, and disconnected at the front;
3. Long and short gold fingers (that is, uneven gold fingers): rectangular pads with different lengths located on the edge of the board.
Features: No character frame and label, usually open window for solder mask layer. Most of the shapes have grooves. The gold finger part protrudes from the edge of the board or is close to the edge of the board. Some boards have gold fingers at both ends. Normal gold fingers are on both sides. Part of the PCR line analyzes the characteristics of the single side of the right side of the whole king pointing to the right, and the wide single root of the whole king finger.
