| 摘要 |
PROBLEM TO BE SOLVED: To avoid a cost increase only by SRAMs or an increase in power consumption only by DRAMs to an increase of a memory capacity by mixedly mounting SRAMs and DRAMs on the same chip and allotting different addresses to the SRAMs and DRAMs respectively. SOLUTION: A core part 1 has an SRAM bank 2-0 and DRAM banks 2-1 to 2-3. Addresses A1 and A0 are allotted to the banks 2-0 to 2-3, e.g. addresses A1 and A0 of the SRAM bank 2 are made [0, 0], and addresses A1 and A0 of the DRAM banks 2-1 to 2-3 are made [0, 1] to [1, 1]. A decoder 7 decodes address signals A1 and A0, and outputs decode signals A00-A11. The SRAM bank 2-0 can be selected by setting A00='H', DRAM bank 2-1 can be selected by setting A01='H', and DRAM banks 2-2 and 2-3 can be selected similarly. |
