4-layer Rogers spray tin PCB board

4-layer PCB means that the printed circuit board is made of 4 layers of fiberglass. There are four routing layers: top, bottom, VCC and GND. Generally, through holes, buried holes and blind holes are used to connect the layers. There are more buried and blind vias than double-sided. In addition, try not to run signal traces on the VCC and GND layers.

4-layer PCB boards have many advantages over double-sided Rogers PCB boards. They can be designed to be more compact, have significantly improved noise immunity, and are easier to lay out.