The distribution density of components on Printed Circuit Board (PCB) should be consistent. Whether it is a single-sided PCB or a double-sided PCB, all components should be installed on the same surface as far as possible. Only when the components on top layer are too dense, some components with limited height and small heat can be installed on the other side, such as SMD components, in order to facilitate the processing, installation and maintenance of the printed circuit board (PCB).
