PCB Design Considerations
Printed circuit board (PCB) design refers to design the circuit layout as per the design principles so as to produce PCB boards at the lowest possible cost. In the past, this usually required the use of expensive special tools to complete. But now, with the increasing popularity of free high-performance PCB design software, PCB designers has been greatly accelerated their design period.
Layout is a problem that PCB designers must face first. It should be noted that temperature-sensitive components, such as sensors, should be set separately from the heat-generating components including the power converter. For designs with multiple power settings, 12- and 15-volt power converters should be placed in different locations on the circuit board, because the heat and electronic noise they generate can affect the reliability and performance of other components.
In the PCB board design process, electromagnetic interference (EMI) is indeed a factor that must be taken seriously. Electromagnetic crosstalk can be coupled with the signal channel, thereby disorganizing the signal into noise, affecting the overall performance of the printed circuit board. If the coupling noise is too high, the signal may be completely covered, so more expensive signal amplifiers must be added to solve the problem. However, if the layout of the signal line can be fully taken into account at the beginning of the circuit board design, the above problems can be avoided.
Capacitance is also an important issue when designing a high-quality PCB board, because it can affect the speed of signal propagation and increase power consumption. The signal channel will couple with the next line or cross the two circuit layers vertically, creating a capacitor inadvertently. By reducing the length of the parallel lines, adding a kink to one of the lines, and thus cutting off the coupling, the above problems can be solved relatively easily.
Capacitance problems are particularly prominent in the design of ground planes. A metal circuit layer may form a coupling with all the circuits above and below it. Although the metal layer does effectively block noise, the metal layer also generates associated capacitance, which affects the operating speed of the circuit and increases the power consumption.
For the design of multilayer circuit boards, the design of vias between different circuit board layers is probably the most controversial issue, because through-hole design will create many problems for PCB fabrication. The through holes between the PCB board layers will affect the signal performance and reduce the reliability of the circuit board design. Therefore, sufficient attention must be paid to it when designing PCB boards.
PCB Design Considerations