Discussion on the Purpose of Making Impedance for FPC Circuit Boards

FPC circuit board impedance refers to the parameters of resistance and reactance, which hinder AC power. Impedance is often represented by Z, which is a complex number. The real part is called resistance, and the imaginary part is called reactance. The blocking effect of capacitance on AC power in a circuit is called capacitive reactance. The blocking effect of inductance on AC power in a circuit is called inductive reactance. The blocking effect of capacitance and inductance on AC power in a circuit is collectively called reactance.



The unit of impedance is ohm. In FPC circuit boards with resistors, inductors, and capacitors, the resistance to alternating current is called impedance. FPC circuit board impedance includes characteristic impedance, differential impedance, odd mode impedance, even mode impedance, and common mode impedance. In the production of FPC circuit boards, impedance processing is essential. The reasons are as follows:



1. The FPC circuit board should consider installing electronic components by plugging. After plugging, issues such as electrical conductivity and signal transmission performance should be considered. Therefore, the lower the impedance, the better. The resistivity should be less than 1&TIMes per square centimeter: 10-6 or less.



2. During the production process of FPC circuit boards, there are process manufacturing steps, and the materials used in these steps must ensure low resistivity to ensure that the overall impedance of the circuit board meets product quality requirements and can operate normally.



3. "There are various types of signal transmission in the conductors of an FPC circuit board. When it is necessary to increase its frequency in order to improve its transmission rate, differences in the impedance value of the circuit itself due to factors such as etching, stack thickness, and wire width will cause changes in its signal distortion, leading to degradation in the performance of the circuit board. Therefore, it is necessary to control the impedance value within a certain range.".