Nowadays, electronic technology is more and more developed. Products such as routers, mobile phones, switches, and base stations are all high-speed signals, which are susceptible to interference and crosstalk. In order to ensure the integrity requirements of high-speed signals, a reasonable design of multi-layer circuit boards can effectively improve the integrity of the signal and reduce the degree of signal interference to an extremely low level.

The design of multi-layer circuit boards is a necessary skill for hardware engineers. Knowing some basic concepts related to multi-layer circuit boards is a requirement for an excellent hardware engineer, so as to be able to grasp the core points in the specific design process . When designing a multi-layer circuit board, you need to pay special attention to the layer design, that is, how the signal lines, power lines, ground, and control lines are divided into each layer. The general principle is that the analog signal and analog signal ground must be at least a separate layer, and a separate layer is also recommended for the power supply.

The general principle of layer arrangement of multi-layer circuit boards:

1. When designing a multi-layer circuit board, the first thing to pay attention to is the distribution of each layer, which is directly related to the performance of the product;

2. The bottom of the device surface (the second layer) is the ground plane, which provides a device shielding layer and a reference plane for the wiring of the device surface;

3. All signal layers are as close as possible to the ground plane;

4. Try to avoid the two signal layers of multilayer circuit boards directly adjacent to each other;

5. The main power supply is as close as possible to it correspondingly;

6. In principle, a symmetrical structure design should be adopted. The meaning of symmetry includes: the thickness and type of the dielectric layer, the thickness of the copper foil, and the pattern;

7. Symmetry of distribution type of multilayer circuit board (large copper foil layer, circuit layer).