This standard defines Wide I/O 2 (WideIO2), including features, functionality, AC and DC characteristics, packages, and micropillar signal assignments. The purpose of this standard is to define the minimum set of requirements for JEDEC compliant, 8 Gb through 32 Gb SDRAM devices with 4 or 8 64-bit wide channels using direct chip-to-chip attach methods for between 1 and 4 memory devices and a controller/buffer device. The WideIO2 architecture is an evolution of the WIO architecture to enable bandwidth scaling with capacity.