An electronic device comprising a semiconductor memory unit that may include a variable resistance element configured to be changed in a resistance value thereof in response to current flowing through both ends thereof, a toggle data generation unit configured to generate toggle data of which logic value toggles with a predetermined cycle, in a first mode for testing reliability of the variable resistance element, a data transfer line configured to transfer data inputted from an outside, and a driving unit configured to flow current which is changed in its direction with the predetermined cycle, through the variable resistance element in response to the toggle data in the first mode, and flow current through the variable resistance element in a direction determined in response to the data of the data transfer line, in a second mode in writing date into or reading data from the variable resistance element.