A 512 Mb Two-Channel Mobile Dram (Onedram) With Shared Memory Array

A 512 Mb two-channel mobile DRAM (OneDRAM) is developed with 90 nm technology. It can operate on a 1.8 V power supply as two separate mobile DDR or SDR DRAMS through each channel with maximum data rate of 333 Mbps/pin because of its exclusive accessibility from each channel to memory arrays. Data exchange between two channels is also possible by sharing one common memory array, and a new control scheme of DRAM for this sharing is proposed. The new control scheme is based on direct addressing mode to achieve compatibility with normal DRAM interface together with fast data transfer speed between two channels.