PCB board has the following three main types of division:
Single-Sided Boards, on the most basic PCB, the parts are concentrated on one side and the wires are concentrated on the other side (where the chip components are on the same side of the wire and the parts on the other side).
This type of PCB is called Single-sided because the wire only appears on one side.
Double-Sided Boards, this circuit board has wiring on both sides, but to use both sides of the wire, you must have the appropriate circuit between the two sides Caixing. The "bridge" between these circuits is called a via.
The pilot hole is on the PCB, filled or coated with metal holes, it can be connected with both sides of the wire. Because the double-panel area doubled the single-panel, double-sided single-board solves the difficulty of staggered wiring.
Multi-Layer Boards, in order to increase the area that can be wired, the multilayer board uses more single or double-sided wiring boards.
With a double-sided for the inner layer, two single-sided for the outer layer or two double-sided, two single-sided outer layer of the printed circuit board, through the positioning system and insulating adhesive material alternately and conductive pattern Printed circuit boards that are interconnected according to design requirements become a four-layer, six-layer printed circuit board, also referred to as a multi-layer printed circuit board.