Circuit boards are divided into three types: single-sided, double-sided, and multi-layer circuit boards according to the number of layers.
Single-sided, on the most basic PCB, control pcb board ，the parts are concentrated on one side and the wires are concentrated on the other side. Since the wires only appear on one side, this type of PCB is called a single-sided circuit board.
Double-sided is an extension of single-sided. There are copper cladding and traces on both sides, and the lines between the two layers can be conducted through vias to form the required network connections.
A multi-layer board refers to a printed board with more than three conductive pattern layers and insulating materials between them, and the conductive patterns are connected to each other as needed.
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