I. welding method
The advantages of this method are simple operation, low cost, high reliability, can avoid the fault caused by poor contact; Disadvantage is the interchange, maintenance is not convenient. This way is generally applicable to the components of the external lead less.
1. PCB wire welding
Do not need any connector, as long as the circuit board with a wire on the external connection point and the board of components or other components can be directly welded to the firm.
Attention should be paid to the interconnection welding of circuit board:
(1) soldering pads for wire shall be placed as far as possible on the edge of the circuit board and arranged in uniform size to facilitate welding and maintenance.
(2) in order to improve the mechanical strength of the wire connection and avoid pulling the wire to remove the solder pad or printed wire, drill a hole near the solder spot on the circuit board to let the wire pass through the through hole on the solder surface of the printed circuit board and insert the solder pad hole into the component surface for welding.
(3) arrange or tie the wires neatly, and fix the wires with wire CARDS or other fasteners and plates to prevent the wires from breaking due to movement.
2. PCB line welding
The two circuit boards are connected by a line, which is reliable and not prone to connection errors, and the relative position of the two circuit boards is not limited.
Direct welding between the printed circuit board, this method is often used for the two printed circuit board between the 90 degree Angle of the connection, connected into a whole circuit board components.
Ii. Connection mode of plug and socket
In more complex instruments and equipment, often using plug connection. This "building block" structure not only guarantee the quality of the product batch production, reduce the cost of the system, and provides convenience for debugging and maintenance. When the equipment malfunction, maintenance personnel do not have to check to level components (i.e. check the cause of the fault, traced back to a specific component. This work will take a considerable amount of time), which is a piece of board as long as the judge abnormal can immediately to replace, in the shortest possible time troubleshooting, shorten downtime, improve equipment utilization. Can replace the circuit board in plenty of time Carry out maintenance and use as spare parts after repair.
1, printed circuit board socket
In more complex instruments and equipment, this kind of connection is often used. This method is to print a plug from the edge of the circuit board.
In the process of plate making, the plug part needs to be gilded to improve wear resistance and reduce contact resistance. Poor reliability, often due to poor oxidized contact of the plug part. In order to improve the reliability of external connection, the same lead wire is often drawn in parallel through the same side or both sides of the contact points on the circuit board.
2. Standard pin connection
This method can be used for external connection of printed boards, especially for small instruments. Two printed boards are connected by a standard pin.