Toward the aim of realizing high-bandwidth, large-capacity nand flash memory-based storage systems, this paper presents a novel daisy-chain downlink interface (I/F) between a controller and a large number of nand packages. The daisy-chain I/F employs a tapered-bandwidth architecture with bridge-by-bridge data extraction based on a proposed spectrally compressed multi-band multiplexing (SCM2) technique to achieve low power consumption. By using the proposed downlink I/F, a nand controller can handle 32 low-cost nand packages while achieving 12.8-Gb/s throughput using two data wires. The fabricated prototype downlink I/F achieved a bit error rate (BER) of 10^-12 with power consumption of 252.1 mW for the transmitter and 375.7 mW for all four receivers together.