3 Tips for PCB Layout
PCB layout is an important part during the whole design process. Layout results will have a direct impact on the wiring results, therefore a reasonable layout is the first step for as successful PCB design. Here are three useful tips for PCB layout design.
1.Determine the number of PCB layers
PCB board size and wiring layer need to be determined in the early stage of design process. The number of wiring layers and the stackup method directly affect the wiring and impedance. The board size helps to determine the stackup method and line width to achieve the desired design results. Currently, the cost difference between multilayer PCBs is very small. It is best to use more circuit layer and copper deposited evenly at the beginning of the design process.
2.PCB Design rules and restrictions
To successfully complete the wiring tasks, wiring tools need to work under the correct rules and restrictions. To classify all the special signal lines, each signal class should have a priority, the higher the priority, the more stringent the rules. The rules relate to the width of traces, the maximum number of vias, parallelism, the interaction between signal lines, and the layers limitations. These rules have a significant impact on the performance of the wring tools. Careful consideration of PCB design requirements is an important step toward successful wiring.
3.PCB components layout
During the optimization assembly process, DFM rules impose restrictions on component layout. If the assembly department allows components to move, the circuit can be properly optimized.
a.In the PCB layout, the power supply decoupling circuit should be designed in the vicinity of the relevant circuit, rather than placed in the power supply section, otherwise not only affect the bypass effect, but also the pulsating current may flow in the power line and ground, resulting in crosstalk;
b.For the power flow within the circuit, you should take the power supply from the last stage to the previous stage, and arrange the power supply filter capacitor in this section near the final stage;
c.For some major current paths, such as disconnecting or measuring current during commissioning and inspection, a current notch should be placed on the conductor during layout. In addition, pay attention to the power supply in the layout, and arrange in a separate PCB.