The design of Automotive PCB single-sided circuit boards requires exposure to a lot of professional data and some physical knowledge, which can be said to be a comprehensive technical project. To make a high-quality circuit board, you need not only a solid foundation, but also sensitivity to impedance. The impedance involved in the PCB board mainly includes the following aspects:

When the direct current of the printed PCB circuit board passes through the wire, it will experience a resistance. This resistance is called resistance, which corresponds to R and the value unit is "ohm" (Ω).

The relationship between resistance and current and voltage is: R=V/I

In addition, resistance is also related to the resistivity (β) of the conductor material, the length of the wire (L), and the cross-sectional area of the conductor (S). R = β L/S

1. Resistance

When an alternating current flows through a conductor, the resistance it receives is called impedance (Impedance), which corresponds to Z and the unit is Ω.

The resistance at this time is different from the resistance encountered by the DC current. In addition to the resistance of the resistance, there are also the resistance problems of inductive reactance (XL) and capacitive reactance (XC).

In order to distinguish the resistance of direct current, the resistance encountered by alternating current is called impedance (Z).

Z=√ R2 +（XL -XC）2

2. Impedance (Z)

In recent years, with the improvement and application of IC integration, the signal transmission frequency and speed are getting higher and higher. Therefore, in the printed board wire, after the signal transmission (emission) reaches a certain value, it will be affected by the printed board wire itself. The impact of this, resulting in severe distortion or complete loss of the transmitted signal. This shows that the "thing" "circulated" by the Automotive PCB wire is not current, but the transmission of square wave signals or pulses in energy.