Knowledge sharing 𞓜 conventional laminated structure of six layer PCB

PCB The laminated structure of circuit board affects its EMC An important factor in performance , It is also an important means to suppress electromagnetic interference . In the multilayer PCB Before board design , We need to first according to the scale of the circuit 、 Board size and electromagnetic compatibility （EMC） Determine the adopted circuit board structure according to the requirements of . Jettoban PCB Xiaobian will introduce the six layers with this article pcb Knowledge of conventional laminated structures .

On some six floors PCB In the design lamination scheme , The shielding effect on electromagnetic field is not good enough , The reduction effect on the transient signal of the power bus is also negligible . That chip has a high density 、 The design with high clock frequency can consider six layers pcb Design .

The first stacking scheme ：SIG－GND－SIG－PWR－GND－SIG; 

This stacking scheme can get better signal integrity , The signal layer is adjacent to the ground plane , Match the power supply layer with the ground plane , The impedance of each wiring layer can be well controlled , And both formations can well absorb magnetic lines of force . besides , On the power supply 、 When the formation is complete, it can provide a better backflow path for each signal layer . 

The second stacking scheme ：GND－SIG－GND－PWR－SIG －GND; 

This stacking scheme is only applicable to the case where the device density is not very high , This kind of lamination has all the advantages of the upper lamination , And the ground plane of the top layer and the bottom layer is relatively complete , It can be used as a better shielding layer . It should be noted that the power supply layer should be close to the non main component surface , Because the ground plane will be more complete . therefore ,EMI Better performance than the first one . 

For the sixth floor pcb design scheme , In order to get better power 、 Ground coupling , The spacing between the power layer and the stratum should be minimized . image 62mil This kind of plate thickness , Although the layer spacing is reduced , It is not easy to control the distance between the main power supply and the stratum very small .

The second scheme is compared with the first scheme , Greatly increase the cost , So we usually choose the first scheme when stacking . In design , To follow 20H Rule and mirror layer rule design .

The above is the sixth floor pcb Introduction to relevant knowledge of conventional laminated structure , I hope it helped you ！

Want to know more about it , You can pay attention to me ！PCB Design -PCB Board making -SMT Patch -BOM Match the order