Special Consideration for VQFN Packages

VQFN packages have a large pad on the bottom side. This pad is not electrically connected to the internal circuit of the chip, but it is mechanically bonded to the internal substrate and serves as a thermal heat sink as well as providing added mechanical stability. This pad must be connected to GND since the ground plane is the best heat sink (largest copper area) of the printed circuit board (PCB).