PCB News - PCB layout design skills and precautions

Grid setting skills in PCB layout design
Different points need to be set in different stages of the design, and large grid points can be used for device layout in the layout stage;
For large devices such as ICs and non-positioning connectors, a grid point accuracy of 50 to 100 mils can be used for layout, while for small passive components such as resistors, capacitors and inductors, a grid point of 25 mils can be used for layout. The accuracy of the large grid points is conducive to the alignment of the device and the aesthetics of the layout.

PCB layout rules:
1. Under normal circumstances, all components should be arranged on the same surface of the PCB board. Only when the top-level components are too dense, can some devices with limited height and low heat generation, such as chip resistors, chip capacitors, and chip capacitors, be installed. Chip IC, etc. are placed on the lower layer.
2. Under the premise of ensuring the electrical performance, the components should be placed on the grid and arranged parallel or perpendicular to each other in order to be neat and beautiful. Under normal circumstances, the components are not allowed to overlap; the arrangement of the components should be compact, and the components should be arranged on the entire layout. The distribution is uniform and dense.
3. The minimum distance between adjacent pad patterns of different components on the circuit board should be above 1mm.
4. The distance from the edge of the circuit board is generally not less than 2MM. The best shape of the circuit board is rectangular, and the aspect ratio is 3:2 or 4:3. When the size of the circuit board is larger than 200MM by 150MM, consider what the circuit board can withstand Mechanical strength.
PCB layout skills:
In the layout design of the PCB, the units of the circuit board should be analyzed, and the layout design should be based on the starting function. When laying out all the components of the circuit, the following principles should be met:
1. Arrange the position of each functional circuit unit according to the circuit flow, so that the layout is convenient for signal circulation, and the signal is kept in the same direction as possible.
2. Take the core components of each functional unit as the center and lay out around him. The components should be uniformly, integrally and compactly arranged on the PCB to minimize and shorten the leads and connections between the components.
3. For circuits operating at high frequencies, the distribution parameters between components must be considered. In general circuits, components should be arranged in parallel as much as possible, which is not only beautiful, but also easy to install and easy to mass produce.