详细介绍了利用allegro PCB设计的方法和技巧。配合大量示意图，介绍了印制电路板设计流程和常用电路模块的PCB处理方法(The method and skill of using Allegro PCB design are introduced in detail. With a large number of schematic diagrams, the design process of printed circuit board and the PCB processing methods of common circuit modules are introduced)