When designing high-level circuit boards, multi-layer circuit boards are usually used instead of single-layer and double-layer circuit boards. Why is this? Today, I brought you the reasons why multilayer boards are used for high-speed circuit boards! Let’s take a look!
Multi-layer boards have many characteristics that single-layer boards and double-layer boards do not have. It is precisely because of these characteristics that the design of high-speed circuit boards uses multilayer boards instead of other circuit boards.
The following is a summary of the characteristics of the multilayer board!
- The power supply is very stable;
- The circuit impedance is greatly reduced;
- The wiring length is greatly shortened;
In addition, from a cost point of view, although the cost of a multi-layer circuit board is higher than that of a single-layer circuit board, if other factors such as the miniaturization of the circuit board and the convenience of noise reduction are taken into account, the multi-layer circuit board and the The cost difference between single-layer circuit boards is not as high as expected. According to the data we know, when we simply calculate the area cost of the circuit board, the area of the double-layer circuit board that can be purchased every day is about 462mm2, and the area of the four-layer circuit board is 26mm2, that is, if the use area of the four-layer circuit board It can be reduced to 1/2 of the double-layer circuit board, and the cost is the same as that of the double-layer circuit board. Although the multi-layer batch will affect the unit area cost of the circuit board, there will not be a 4 times price difference. If there is a price difference of more than 4 times, just try to reduce the use area of the circuit board, and try to reduce it to less than 1/4 of the double-layer board.