How is a 6 layer PCB made?
The 6-layer board can separate the analog ground from the digital ground because there can be two layers of ground in the PCB board. Regarding whether it is unified or separate, it involves the problem of the minimum return path of the signal in electromagnetic interference. After drawing the schematic diagram, don't forget to check the error and check the package manager to check the Electroniccomponents package. After the creation is completed, the schematic network table can be imported into the PCB file. The next thing to do is to set the layer structure (layer stack manager). add layer is to add an intermediate signal layer, and add plane is to add an internal power supply and an internal ground layer. The middle signal layer is the same as the top and bottom layers. Where signal lines are placed, the signal lines represent copper, and the places without signal lines are insulated. The internal power supply and the ground layer generate a copper mold. The line used when dividing the internal electrical layer represents the corroded copper, that is to say, the dark red represents the corroded copper, and the other areas represent the copper mold. Another point is that the power supply layer and the main ground layer should be tightly coupled, and an interval of 5 mils (prepreg) is preferable. The main principle of thebuile-up printed board layout is to do a good job of partitioning, that is, the partitioning of analog devices and digital devices, which can reduce interference, because the interference generated by digital signals is large, and the anti-interference is also strong, while the interference generated by analog signals is relatively small, but vulnerable Digital signal interference. Another point is to pay attention to the layout of components sourcing with different operating voltages, and devices with large voltage differences should be far apart. For some Electronic Resistor and Capacitor decoupling capacitors, the closer to the pin, the better. The other thing to pay attention to is that the pins of the same network are close, and the communication PCB layout is beautiful.
In principle, there are 3 signal layers and 3 power layers, of which GND is two layers 2, 5, and the middle layers 3 and 4 are Power and middle signal layers. If there are few wires in the middle signal layer,Metal Core PCB (MCPCB) copper can be applied to Power on the middle signal layer.
Each signal layer is adjacent to the inner electric layer, and there is no directly adjacent signal layer, which avoids signal crosstalk between layers;
The high-speed signal line can be arranged on the signal layer 5, so that it can be effectively shielded by the ground layer and the power layer. DRC inspection is very important. After the HDI PCB board is drawn, it must be carried out to check whether there is anything that violates the rules and is not found.
