Semiconductor memory device having rank interleaving operation in memory module

The present invention relates to a semiconductor memory device for performing rank interleaving operation in the memory modules. The semiconductor memory device comprises a second memory area which is accessed independently of the first memory area to the chip and is formed in the same chip select signal depending on the said first memory area formed in the chip. First and second memory areas are shared command and address lines and to perform interleaving operations in accordance with the rank select signal used.