Good quality Hdi - 6 Layer High Tg Board | YMS PCB – Yongmingsheng

　　When the trace on the PCB matches the file transfer rate, the signal can avoid interference.However, impedance control must be performed at speeds of 100Mhz or higher. Impedance control is the practice of laying down printed circuit traces whose impedance matches the circuit elements to which they are connected.That is, the tracking width and distance from the ground plane are adjusted to treat the track as an appropriate RF feeder with the specified characteristic impedance.

　　By the way, there are four main factors affecting impedance control on PCB: dielectric constant, copper thickness, wirewidth and reference plane.