After the wiring of the circuit board is completed, the circuit board should be checked for design rules to ensure that the circuit board meets the design requirements and all networks have been correctly connected. Commonly used inspection items in design rule inspection are as follows

1. Whether the distance between line and line, line and component pad, line and via, component pad and via, via and via is reasonable, and whether it meets the production requirements.

2. Whether the width of the power line and the ground line is appropriate, whether the power supply and the ground line are tightly coupled, and whether there is a place in the middle to widen the ground line.

3. Whether the best measures have been taken for the key signal lines, such as the shortest length, the protection line, the input line and the output line are clearly separated.

4. Whether there are separate ground wires for analog circuit and digital circuit.

5. Whether the graphics (such as icons and annotations) added to the PCB will cause signal short circuit.

6. Whether to modify some unsatisfactory lines.

7. Whether there is a process line on the PCB, whether the solder mask meets the requirements of the production process, whether the solder mask size is appropriate, and whether the character logo is pressed on the device pad.

8. Whether the edge of the outer frame of the power ground layer in the multilayer board is reduced, such as the exposed copper foil of the power ground layer, which may cause a short circuit.

Design rule inspection results can be divided into two types: one is Report (report) output, which generates inspection result reports; the other is On Line inspection, which is to inspect the electrical rules and wiring rules of the circuit board during the wiring process.