På computerens hukommelsespinde og grafikkort kan vi se en række gyldne ledende berøringsplader, som kaldes “guldfingre”. In PCB design and production industry, Gold Finger, or Edge Connector, is used as the outlet of the board through the Connector Connector. Next, let’s understand the processing method and some details of the gold finger in PCB.

Goldfinger PCB overfladebehandling

1, electroplating nickel gold: thickness up to 3-50U “, because of its excellent conductivity, oxidation resistance and wear resistance, is widely used in the need to often plug and pull out of the goldfinger PCB or need to often carry out mechanical friction ON the PCB board, but because of the high cost of gold plating, only used in the local gold plating process such as goldfinger.

2, heavy metal, thickness of conventional 1 u “, up to 3 u “because of its superior electrical conductivity, smoothness and weldability, are widely used in such as buttons, binding IC, BGA design of high precision PCB, goldfinger PCB for wear-resisting performance requirements is not high, also can choose the whole plate zedoary process, and the process cost is electric gold process cost is much lower. Farven på guldvasken er gylden gul.

PCB guldfinger detaljer behandling

1) For at øge slidstyrken på guldfingre skal guldfingre normalt være belagt med hårdt guld.

2) Guldfingeren skal affases, normalt 45 °, andre vinkler som 20 °, 30 ° osv. If there is no chamfering in the design, there is a problem; Affasningen på 45 ° i PCB er vist nedenfor:

3) Golden finger needs to do the whole block blocking welding window opening process, PIN does not need to open the steel net;

4) Minimumsafstanden mellem tin-sink og sølv-sink puder og toppen af ​​fingeren er 14mil; It is recommended that the pad should be more than 1mm away from the finger, including the through-hole pad;

5) Do not lay copper on the surface of the finger;

6) All layers of the inner layer of gold finger need to be coppered, usually with a width of 3mm; Can do half finger coppers and whole finger coppers.

D: Is the “gold” of goldfinger gold?

First, let’s understand two concepts: soft gold and hard gold. Blødt guld, normalt af en blødere tekstur. Hard gold, usually a compound of hard gold.

The main role of gold finger is to connect, so it must have good electrical conductivity, wear resistance, oxidation resistance, corrosion resistance.

Because pure gold (gold) is relatively soft, gold fingers generally do not use gold, but just a layer of “hard gold (gold compound)”, which can not only get good electrical conductivity of gold, but also can make it wear resistance, oxidation resistance.

Så PCB har ikke brugt “blødt guld”? Svaret bruges naturligvis, såsom kontaktfladen på nogle mobiltelefonnøgler, aluminiumstråden On THE COB (Chip On Board). Brugen af ​​blødt guld er generelt nikkelguldudfældning ved galvanisering på kredsløbskortet, dets tykkelsesregulering er mere elastisk.