What is a characteristic impedance pcb board?

Characteristic impedance refers to the resistance of the high-frequency signal or electromagnetic wave in the propagation process of the transmission signal line relative to a certain reference layer at a certain frequency, which is also called characteristic impedance. It is equivalent to a vector sum of electrical impedance, inductive reactance, and capacitive reactance.
 
What’s the point of making characteristic impedance pcb board?
Characteristic impedance is the core of solving signal integrity problems. With the continuous development of pcb electronic products towards high frequency and high speed, the circuit performance provided by PCB board must ensure that the signal does not reflect during the transmission process and keep the signal intact and undistorted. In order to ensure signal integrity, the characteristic impedance (Z0) of the signal line of the PCB must be matched with the “electronic impedance” of components; when electronic devices such as computers and communication switches are in operation, the signals sent by the drive components need to pass through the PCB The signal line reaches the receiving element.
 
Impedance-actually refers to the parameters of resistance and reactance, because the PCB circuit (board bottom) should consider plugging and installing electronic components, and the conductivity and signal transmission performance should be considered after plugging. Therefore, the lower the impedance, the better.