Patent ID: 7331011

Claim:
A semiconductor integrated circuit device, comprising: a first word line and a second word line, which are selected on the basis of an address; a pair of complementary bit lines for information bits; a pair of complementary bit lines for parity bits; a first memory cell coupled to the first word line and one of the pair of complementary bit lines for information bits; a second memory cell coupled to the first word line and one of the pair of complementary bit lines for parity bits; a third memory cell coupled to the second word line and another of the pair of complementary bit lines for information bits; a fourth memory cell coupled to the second word line and another of the pair of complementary bit lines for parity bits; column switches which connect the pair of complementary bit lines for information bits to a pair of data lines for information bits and the pair of complementary bit lines for parity bits to a pair of data lines for parity bits; and a logic correction circuit connected to one of the pair of data lines for parity bits, the logic correction circuit executing a parity bit rewrite operation in which, on the basis of the address, a logic of data read out from the data lines for parity bits is inverted in a data read operation, and a logic of data to be written in the data lines for parity bits is inverted in a data write operation, wherein the pair of complementary bit lines for information bits and the pair of complementary bit lines for parity bits are twisted bit lines, the logic correction circuit determines whether a selected word line crosses a reversed phase column and whether a selected column is the reversed phase column, and, when the selected word line crosses the reversed phase column, and the selected column is the reversed phase column, the logic correction circuit does not execute the parity bit rewrite operation.