Common Mistakes in Schematic and PCB Diagrams

• Common Errors in Schematic Diagrams:

  • Signal connections missing from the ERC report pin due to:
  • Missing I/O attributes for pins defined during package creation
  • Inconsistent grid settings altering connections when components are created or placed
  • Reversed pin directions during component creation leading to unconnected ends
  • Components extending beyond the drawing boundary, often caused by improper centering within the component library
  • Partial import of netlist into the PCB project file due to global option not selected during netlist generation

• Common Errors in PCB Design:

  • Error reported: “NODE not found” when loading the network because:
  • Components in the schematic use packages not present in the PCB library
  • Components in the schematic use packages with mismatched names in the PCB library
  • Components in the schematic use packages with mismatched pin numbers compared to the PCB library
  • Difficulty in printing the design on a single page due to improper design origin setting and component movement
  • DRC reporting network divided into multiple sections indicating incomplete connectivity

• Additional Tips:

  • Use Windows 2000 to reduce the risk of system crashes
  • Export files multiple times to create new DDB files for reduced size and minimized freezing risks
  • Avoid relying solely on automatic routing for complex designs

• PCB Routing Best Practices:

  PCB routing is a critical step in product design, involving single-sided, double-sided, and multilayer routing methods. Interactive routing can pre-wire critical lines before automatic routing. Ground wires can be used for isolation, and routing of adjacent layers should be perpendicular to minimize interference.

• Efficient Automatic Routing:

  Automatic routing efficiency depends on well-organized layouts with preset routing rules. Start with complex routes, connect short wires quickly, and optimize the global routing path for enhanced performance.

• Advanced PCB Design Techniques:

  In high-density designs, blind and buried-hole technologies conserve routing channels, making the design process more efficient.

• Mastering PCB Design:

  PCB design mastery requires hands-on experience and practice by electronic engineering designers.