What is the PCB basic knowledge
Apr 22, 2022
A circuit board (also known as a PCB board) is a version with printed wires. Its main function is to reduce the space occupied by the wires and organize the wires in a clear layout.
The circuit board is the result of the processing of the copper clad laminate, which is made by covering a piece of copper foil on the surface of the insulating substrate.
Copper clad laminates are usually processed using etching. The method is to apply corrosion-resistant material to the lines to be retained on the copper clad laminate, and then use chemical agents to etch the rest away, and the rest is the copper foil used as the wire.
When looking at the actual board, there are places where the wire is wider, even a large piece (usually the ground wire). This is based on the formula current = voltage/resistance , reducing the effect of the resistance of the wire on the magnitude of the current. Usually the relationship of line width is: ground wire > power wire > signal wire.
How to get the PCB board?
Usually, the PCB diagram is not drawn directly in one step, but the circuit is first drawn and then converted into a PCB diagram.
Below is an example of a PCB that uses a micro usb to light up an LED light.
Step 1: Circuit Diagram
The Step 2: PCB Diagram
Step3: take a look at the preview of the board in 2D:
Step 4: preview in 3D:
Usually, the components are tightly attached to the circuit board to reduce the volume, and they are soldered on the other side of the board, so there will be pads on the back. After the hole is punched, since the middle of the board is an insulating layer, it is necessary to coat the hole wall with a metal layer and connect it to the pad on the back for conduction.
Step 5: The part of a PCB
Device: Components. On the PCB light board, the device appears in the form of pad + silk screen.
Pad: The pad contains the lead hole and the surrounding copper foil.
Trace: wire.
Via: A hole that connects wires across layers.
Silk screen: Mark information on the board with numbers or letters.
Solder Mask: Avoid mis-soldering adjacent but disconnected pins during soldering.
