 Specifically, 48 connection pads along the sides and one large thermal pad (connected to ground) on the bottom.The ESP32 system on a chip integrated circuit is packaged in both 6 mm × 6 mm and 5 mm × 5 mm sized QFN packages.The ESP32-PICO-D4 system in package module combines an ESP32 silicon chip, crystal oscillator, flash memory chip, filter capacitors, and RF matching links into a single 7 mm × 7 mm sized QFN package.