Electronic and electromechanical devices contain electrical contacts, and the electrical connection that connects two separate contacts is called an interconnection. In order to fulfill a specified function, electronic devices must be interconnected according to the circuit schematic.

PCB circuit boards, as a component of the whole machine, generally do not constitute an electronic product, there must be external connection problems. For example, electrical connections are required between printed boards, between printed boards and external components, and between printed boards and equipment panels. One of the important elements of printed board design is to select the connection with the best reliability, manufacturability and economy. There are many types of external connections, which should be chosen flexibly according to different characteristics.

I. Interconnection of circuit boards I: soldering

The advantages of this connection method is simple, low cost, high reliability, can avoid the failure caused by poor contact; disadvantage is that the exchange and maintenance is not convenient. This method is usually applied to parts with fewer external leads.

1, PCB lead welding

This method does not require any connection plug-ins, just use the wires to PCB printed board on the external connection point directly welded to the board outside the part or other parts. For example, speakers in radios, battery boxes, etc.

II. Circuit board welding should be noted:

(1) The pads for soldering wires should be located as close as possible to the edge of the PCB printed board and arranged in a uniform size to facilitate soldering and maintenance.

(2) In order to improve the mechanical strength of the wire connection and avoid pulling the pads or printed wires due to wire pulling, holes should be drilled near the solder joints on the PCB printed board so that the wires pass through the through holes on the soldering surface of the printed board, and then the holes of the pads should be inserted into the surface of the components for soldering.

(3) Through the wire card or other fasteners will be neatly arranged or bundled wires, and the board is fixed to avoid wire breakage due to movement.

2, PCB cable welding

Between the two PCB circuit boards using wiring connection, reliable and not easy to connect the error, the relative position of the two PCB printed boards are not restricted. Direct welding of printed boards, usually used to connect the two printed boards between the 90-degree angle. After connection, it becomes a whole PCB printed board assembly.

III. Circuit board connection mode II: plug-in connection mode

Plug-in connection is usually used for complex instruments and equipment. This "building block" structure not only ensures the quality of mass production of products, reducing the system cost, but also for the debugging and maintenance provides a convenient. When a device fails, maintenance personnel do not need to check the component level (i.e. check the cause of the failure and trace it back to a specific component. This task takes a considerable amount of time). As long as it is determined which board is not working properly, it can be replaced immediately, eliminating the problem in the shortest possible time, reducing downtime and increasing equipment utilization. Replacement boards can be repaired in plenty of time

1、Printed board socket

This connection method is usually used for more complex instruments and equipment. This method is to make a printed plug from the edge of the PCB printed board. The plug is partially designed to match the size of the socket, the number of contacts, the distance of the contacts and the position of the locating holes to match the particular PCB printed board socket.

When making the board, the plug needs to be gold plated to improve wear resistance and reduce contact resistance. The method is simple to assemble, interchangeable and maintainable, and is suitable for standardization in mass production. The disadvantages are the increased cost of printed boards, higher manufacturing accuracy and process requirements for printed boards; slightly lower reliability, poor contact due to oxidation of the plug part or aging of the socket. In order to improve the reliability of the external connection, usually through the circuit board on the same side or both sides of the contacts in parallel to lead to the same lead.    PCB printed circuit board socket connection is commonly used in multi-board structure products, socket and printed circuit board or base plate has two types of pins.

2, standard pin connection

This method can be used for the external connection of the printed board, especially in small instruments. Two printed boards are connected by standard pins. The two printed boards are generally parallel or perpendicular, easy to mass production.

The above is the PCBA processing plant to provide the relevant knowledge, if you have a different opinion or want to know more information about the partners, you can directly contact Shenzhen Xinfeijia Technology Co!