Factory source Pcb Print Service - 10 Layer ENIG FR4 Impedance Control PCB – Huihe

Why Control Impedance On PCBs?

When a signal requires a specific impedance to function properly, a controlled impedance should be preferred. In high-frequency applications, a complete electronic board with constant impedance is essential to protect transmitted data from corruption and maintain signal clarity. The longer the trajectory or the higher the frequency, the more adaptation is required. Any lack of rigor at this stage can increase the switching time of electronic devices or circuits and lead to unexpected errors. 

Once the component is installed on the circuit, the uncontrolled impedance is difficult to analyze. Components have different tolerance capabilities depending on their batch. In addition, their specifications are subject to temperature changes, which can lead to failures. In this case, replacing the component may seem like the solution at first, but in fact, inappropriate trace impedance is the root of the problem.

This is why trace impedance and its tolerances must be checked early in printed circuit board(PCB) design. The designer must work hand in hand with the manufacturer to ensure that the value of the component is met.

Impedance characteristics of PCB

PCB tracking impedance has several characteristics to study impedance. PCB board design impedance includes: permittivity, length, width, height, PCB manufacturing limits/tolerances, and distance characteristics between track and other copper.

Applications Of Impedance Control PCB

Impedance control involves measuring the impedance of certain conductive paths during board manufacturing and ensuring that it is within the limits communicated by the designer. This technique is expensive, but it has become socially acceptable since the early 2000s as the frequency of electronic components continues to increase. For example, use it in the following products:

Analog and digital telecommunications

Video signal processing

Internet box, TV, GPS, video game, digital camera

Computers, tablets, phones

Motor control module

phone

Internet box

computer

video game

GPS

digital camera