Abstract: A semiconductor device includes first and second lines, and a switch between the first and second lines. The switch temporary and electrically connects the first and second lines to each other, when the first signal line is transitioned from a first level to a second level while the second signal line is transitioned from the second level to the first level.

Abstract: A semiconductor device includes first and second lines, and a switch between the first and second lines. The switch temporary and electrically connects the first and second lines to each other, when the first signal line is transitioned from a first level to a second level while the second signal line is transitioned from the second level to the first level.

Abstract: A semiconductor device selects one mask pattern among from a plurality of the mask patterns, which are stored in a mask resister circuit for mask controlling of a bit width (vertical axis), by a mask pattern selection signal, and controls input and output of data based on the selected mask pattern and a mask control signal of a bit string (horizontal axis), when inputting and outputting data having the consecutive bit string (horizontal axis) and a plurality of the bit widths (vertical axis). A read data converter circuit and a write data converter circuit select to mask or unmask each data signal during burst reading or writing, and masks the data signal. The masked data signal is not written in a memory cell by inactivating a write data buffer circuit during writing, and is not read out by inactivating a data driver circuit connecting with an external input and output terminal.