PCB is made from different components and a variety of complex processes and technologies, among which the structure of PCB circuit board has single-layer, double-layer and multi-layer structure, and the manufacturing methods of different hierarchical structures are different.
Today, manufacturer PCB from the following three aspects to popularize the components of PCB board name and corresponding USES, and PCB single-layer, double-layer, multi-layer structure of the production and a variety of types of work level of the main functions.
First, the printed circuit board is mainly composed of welding pads, through holes, mounting holes, wires, components, connectors, filling, electrical boundaries, etc. The main functions of each component are as follows:
Solder pad: the metal hole used to weld the component pin.
Through hole: a metal hole used to connect the pins of components between layers.
Mounting hole: used for fixing printed circuit board.
Conductor: electrical network copper film used to connect the pins of components.
Connector: a component used for connecting circuit boards.
Filling: copper coating for ground wire network, which can effectively reduce the impedance.
Electrical boundary: used to determine the size of the circuit board, all components on the circuit board must not exceed this boundary.
Second, common board Layer structure of printed circuit board includes Single Layer PCB, Double Layer PCB and Multi Layer PCB. The brief description of these three board Layer structures is as follows:
(1) single-layer board:
That is, only one side of the copper and no copper on the other side of the circuit board.Usually components are placed on the side without copper coating, which is mainly used for wiring and welding.
(2) double-layer board:
That is, two sides are covered with copper circuit board, usually called one side of the Top Layer, the other side of the Bottom Layer.Generally, the top layer is used as the component surface and the bottom layer as the component welding surface.
(3) multi-layer board:
That is, the circuit board contains multiple working layers, including several intermediate layers in addition to the top layer and the bottom layer. Usually, the intermediate layer can be used as the conductor layer, the signal layer, the power supply layer and the connection layer.The layers are insulated from each other, and the connections between layers are usually made through holes.
Thirdly, the printed circuit board includes many types of working layers, such as signal layer, protection layer, screen printing layer, internal layer, etc., the functions of various layers are briefly introduced as follows:
(1) signal layer:
Mainly used for placing components or wiring.Protel DXP usually consists of 30 middle layers, namely Mid Layer1~Mid Layer30. The middle layer is used to lay the signal line, and the top layer and the bottom layer are used to place the components or copper coating.
(2) protective layer:
Mainly used to ensure that the circuit board does not need to be coated with tin, so as to ensure the reliability of the circuit board operation.The Top Paste and Bottom Paste are the Top layer and the Bottom layer respectively.On Top Solder and Bottom Solder, respectively, are the Solder Solder protection layer and the Bottom Solder protection layer.
(3) screen layer:
It is mainly used to print the serial number, production number and company name of components on printed circuit board.
(4) internal floor:
Mainly used as a signal wiring layer, Protel DXP contains a total of 16 internal layers.
(5) other floors:
There are mainly four types of layers.
(6)Drill Guide(Drill azimuth layer) :
It is mainly used for drilling holes on printed circuit boards.
Above is the composition of PCB and part of the main functions of the introduction, I hope to help you.
Post time: May-31-2020