| 摘要 |
A QFN integrated circuit 29 is mounted on a leadframe having multiple lead lands 23, 25, and resin material 28 encapsulates the integrated circuit 29 leaving the lead lands 23, 25 exposed. Subsequently a sawing operation divides the lead lands.23, 25 into multiple leads, and the lead frame and resin material are partitioned to form packages. The pitch of the resultant leads is not limited by the pitch of the lead lands of the leadframe, so the leadframe can be of the relatively cheap stamped leadframe variety, in which the pitch of the lead lands is higher than the desired pitch of the leads of the completed package. The sawing operation may further include reshaping the diepad area 21 of the leadframe to produce heat sink fins, for improved heat dissipation. The proposed process is suitable both to produce packages including only a single integrated circuit, and also to produce multi-chip modules. |
