Abstract: A memory device includes a memory cell array, a data accessing circuit, a data bus inversion calculator, a multiplexer, and an output result judging circuit. The data accessing circuit performs a data write-in operation or a data read-out operation on the memory cell array. The data accessing circuit reads read-out data from the memory cell array. The data bus inversion calculator generates inversion indication data according to the read-out data. The multiplexer outputs the inversion indication data or test data according to a mode signal. The output result judging circuit compares the read-out data with the inversion indication data or the test data to generate output information.

Abstract: A memory device includes a memory cell array, a data accessing circuit, a data bus inversion calculator, a multiplexer, and an output result judging circuit. The data accessing circuit performs a data write-in operation or a data read-out operation on the memory cell array. The data accessing circuit reads read-out data from the memory cell array. The data bus inversion calculator generates inversion indication data according to the read-out data. The multiplexer outputs the inversion indication data or test data according to a mode signal. The output result judging circuit compares the read-out data with the inversion indication data or the test data to generate output information.

Abstract: A DRAM circuit includes an array having a normal word line, a first redundant word line and a second redundant word line immediately adjacent to the first redundant word line. The second redundant word line is activated if the normal word line is assigned, by a memory controller external to the DRAM circuit, to be activated. A redundant refresh circuit is configured to determine that the first redundant word line is required to be refreshed in response to the second redundant word line being activated; and a row decoder is configured to, according to the determination of the redundant refresh circuit, refresh the first redundant word line.