Pcb by different components and a variety of complex process technology processing and other production, which pcb circuit board structure has a single layer, double layer, multi-layer structure, different levels of structure of its production is different. This article will introduce in detail: pcb circuit board component name and corresponding use, and pcb circuit board single layer, double layer, multi-layer structure of the production and the main function of the various types of working level.

First, the printed circuit board is mainly composed of pads, over holes, mounting holes, wires, components, connectors, filler, electrical boundaries, etc., the main functions of each component are as follows:

Solder pads: metal holes used for soldering component pins.

Over-hole: metal holes used to connect component pins between layers.

Mounting holes: used to fix the printed circuit board.

Wire: Copper film used to connect the component pins of the electrical network.

Connectors: Components used to connect between circuit boards.

Filling: Copper laying for the ground network, which effectively reduces impedance.

Electrical boundary: used to determine the size of the circuit board, all the components on the circuit board can not exceed the boundary.

Second, the common printed circuit board layer structure includes single-layer board (Single Layer PCB), double-layer board (Double Layer PCB) and multi-layer board (Multi Layer PCB) three kinds of these three kinds of layer structure is briefly described below:

(1) single-layer board: that is, only one side of the copper and the other side of the circuit board without copper. Usually components are placed on the side without copper, copper side is mainly used for wiring and soldering.

(2) Double-layer boards: that is, both sides of the copper circuit board, usually called one side for the top layer (Top Layer), the other side for the bottom layer (Bottom Layer). Generally, the top layer as a place to place the component surface, the bottom layer as a component welding surface.

(3) multilayer board: that is, contains more than one working level of the circuit board, in addition to the top layer and the bottom layer also contains a number of intermediate layers, usually the middle layer can be used as a wire layer, signal layer, power supply layer, grounding layer, and so on. Layers and layers are insulated from each other, layer to layer connection is usually achieved through vias.

Third, the printed circuit board includes many types of working level, such as signal layer, protective layer, silkscreen layer, internal layer, etc., the role of the various levels are briefly described below:

(1) Signal layer: mainly used to place components or wiring. Protel DXP usually contains 30 intermediate layers, i.e. Mid Layer1~Mid Layer30, the intermediate layer is used to lay out the signal lines, and the top and bottom layers are used to place components or lay copper.

(2) Protection Layer: It is mainly used to ensure that the places on the circuit board that do not need to be tinned are not tinned, so as to ensure the reliability of the circuit board operation. Top Paste and Bottom Paste for the top layer of soldermask and bottom layer of soldermask; Top Solder and Bottom Solder for the solder paste protection layer and bottom layer of solder paste protection layer. (3) Screen Printing Layer: Mainly used in the printed circuit board printed on the components of the running number, production number, company name, etc..

(4) Internal layer: mainly used as a signal wiring layer, Protel DXP contains a total of 16 internal layers. (5) Other layers: mainly includes 4 types of layers.

(5) Other layers: mainly includes 4 types of layers.

Drill Guide (Drill Orientation Layer): Mainly used for the location of drill holes on the printed circuit board.