Development of modern scientific technology leads to the increasing miniature of electronic components and massive application of SMT technology and devices in electronic products. SMT manufacturing device has attributes of full auto, high precision and high speed. Because degree of automation rises, higher requirements are brought to PCB design. PCB design must cater to SMT device requirements, otherwise manufacturing efficiency and quality will be influenced or even computer automatic SMT possibly fails to be completed. For example, the machine will possibly frequently break down when MARK isn't fully met; unreasonable design in terms of PCB shape, clamping edge and panel will influence manufacturing efficiency and pad defects or even machinery manufacturing can't be completed.