Shenzhen Circuit board manufacturers, Shenzhen impedance control circuit board, Shenzhen High Frequency PCB
Circuit board manufacturers talk about PCB circuit board why do impedance control?

The impedance of the PCB board refers to the resistance and the parameters of the reactance, it acts as a hinder the AC. Impedance control is essential in the production of PCB boards. The reasons are as follows:
 

1. The PCB circuit board should be considered for mounting of electronic components. After mounting, the conductive performance and signal transmission performance should be considered. Therefore, the impedance control should be as low as possible, and the resistivity should be less than per square centimeter 1 times 10 to the negative six powers.


2. In the production process, the impedance circuit board must undergo the process of PTH (Plated Through Hole), HAL (Hot Air Leveling), soldering of the connector, etc., and the materials used in these processes must ensure low resistivity, then in order to ensure that the overall impedance of the circuit board is low, it meets the product quality requirements and can operate normally.
 

3. The tin-plating of the impedance circuit board is the most prone to problems in the whole circuit board production, and is the key process affecting the impedance board. The biggest defect of the electroless tin plating layer is that it is easy to change color (both easy to oxidize or deliquesce), and the soldering property is poor, which may cause the PCB board to be difficult to solder, the impedance is too high, and the conductivity is poor or the performance of the whole board is unstable.
 

4. There are various signal transmissions in the conductors in the impedance circuit board. When the transmission rate is increased, the frequency must be increased. If the line itself is different due to etching, stack thickness, wire width, etc., the impedance value will change and the signal will be distorted, resulting reduce the performance of the PCB. Therefore, it is necessary to control the impedance value within a certain range.