摘要
Problems about surface mounting process for fine pitch devices and reasons on solder bridging of L type lead devices welded are depicted. Bridging mechanism and influence factors are analyzed with two-dimensional geometric model. Based on this, high-density surface mount technology ( SMT) for fine pitch L type lead devices heated by scanning laser is raised. Surface mount process for QFP208 on printed circuit board (PCB) is studied. The results of tests are that it is quite possible to solve the solder bridging of surface mounting for fine pitch devices with scanning laser-heating method.
Problems about surface mounting process for fine pitch devices and reasons on solder bridging of L type lead devices welded are depicted. Bridging mechanism and influence factors are analyzed with two-dimensional geometric model. Based on this, high-density surface mount technology ( SMT) for fine pitch L type lead devices heated by scanning laser is raised. Surface mount process for QFP208 on printed circuit board (PCB) is studied. The results of tests are that it is quite possible to solve the solder bridging of surface mounting for fine pitch devices with scanning laser-heating method.