BTCs are a family of leadless packages where electrical connections consist entirely of metallized terminals on the bottom surface. Common package types covered by IPC-7093A include: (Quad Flat No-lead) DFN (Dual Flat No-lead) LGA (Land Grid Array) SON (Small Outline No-lead) MLP/MLF (Micro Leadframe Packages) Key Design Enhancements in IPC-7093A
Revision A introduced state-of-the-art guidance focused on reliability and process optimization: Thermal Tab and Solder Paste Discussion - PCB Libraries ipc-7093a pdf