The PCB design seems to be complicated. It is necessary to consider the direction of various signals and the transmission of energy. The distress caused by interference and heat is also always present. But in fact, the summary is very clear and can be started from two aspects: the straightforward ones are: 'how to put' and 'how to connect'.
1. Follow the layout principle of 'first big and then small, first difficult and easy', that is, important unit circuits and core components should be prioritized. This is the same as eating a buffet: the appetite of the buffet is limited to pick the favorite food, and the PCB space is limited to pick the important pendulum.
2. The layout should refer to the principle block diagram, and arrange the main components according to the main signal flow direction of the board. The layout should try to meet the following requirements: the total connection is as short as possible, and the key signal line is the shortest; the layout of the decoupling capacitor should be as close as possible to the power supply pin of the IC, and the loop formed between the power supply and the ground should be the shortest; Run the road to prevent accidents on the road.
3, the arrangement of components should be easy to debug and repair, that is, small components can not be placed around the components, there must be enough space around the components to be debugged, making the situation too crowded will often become very embarrassing.
4. For the same structural circuit part, adopt the 'symmetric' standard layout as much as possible; optimize the layout according to the standard of uniform distribution, balance of center of gravity and beautiful layout. Baineng Network is a subsidiary of Qinji Group. It is a leading electronic industry service platform in China. It provides components, sensor procurement, PCB customization, BOM distribution, material selection and other electronic industry supply chain solutions. The overall needs of small and medium-sized customers in the industry.
5. The same type of plug-in components should be placed in one direction in the X or Y direction. The same type of polar discrete components must also strive to be consistent in the X or Y direction for ease of production and inspection.
6, the heating components should be generally evenly distributed, in order to facilitate the heat dissipation of the single board and the whole machine, temperature sensitive components other than temperature detection components should be away from the components with large heat.
7. The high voltage, high current signal is separated from the low current and low voltage weak signals; the analog signal is separated from the digital signal; the high frequency signal is separated from the low frequency signal; the interval of the high frequency components is sufficient. When disposing of components, it should be considered that devices using the same power supply should be placed together as much as possible to facilitate future power separation.
The above is the main consideration for the 'how to put' layout. And the 'how to connect' is relatively more complicated, in general:
Key signal line priority: simulate key signal priority routing such as small signal, high speed signal, clock signal and synchronization signal;
Density-Priority Principle: Start wiring from the most complex devices on the board. Start wiring from the densest area of the board connection.
The difference between PCB and PCBA
What is a PCB? How did PCBA evolve? What is the difference between PCB and PCBA? Let's take a closer look below.
PCB is the abbreviation of Printed Circuit Board. Because it is made by electronic printing, it is called "printing" circuit board. PCB is an impor...