In the transmission signal line of an electronic device, the resistance encountered when the high-frequency signal or electromagnetic wave propagates is called impedance. Why do pcba manufacturing boards have to be impedance during the manufacturing process? Let us analyze from the following 4 reasons:
1. The PCB circuit board should consider plugging and installing electronic components. The later SMT patch connection also needs to consider issues such as conductivity and signal transmission performance, so the lower the impedance, the better.
2. The PCB circuit board undergoes copper sinking, electrolytic tin plating (or chemical plating, thermal spray tin), and connector soldering during the production process. The materials used must require low resistivity to ensure the overall impedance value of the circuit board. It can operate normally only if it meets the product quality requirements.
3. The tin plating of pcb circuit board is the most prone to problems in the whole circuit board production, and it is the key link that affects impedance; its biggest defect is easy oxidation or deliquescence, poor solderability, which makes the circuit board difficult to solder and excessive impedance. High, resulting in poor electrical conductivity or instability of the overall board performance.
4. The conductors in the pcb circuit board will transmit various signals. The circuit itself will change the impedance value due to the etching, stack thickness, wire width and other factors, which will cause the signal to be distorted and the performance of the pcb prototype circuit board. You need to control the impedance value within a certain range
