Patent attributes
A memory cell arranged between first and second wirings includes a variable-resistor element. A controller controls a voltage applied between the first and second wirings. The controller performs a first operation that applies a first voltage between the first and second wirings to switch the variable-resistor element from a first state with a resistance value not less than a first resistance value, to a second state with a resistance value not more than a second resistance value smaller than the first resistance value. The second operation applies a second voltage smaller than the first voltage between the first and second wirings to switch the variable-resistor element from the second state to the first state. In the first operation, a verify voltage is applied between the first and second wirings. Based on the obtained signal, a third voltage smaller than the first voltage is applied between the first and second wirings.
