Patent ID: 8575985
Filing Date: 2013-11-05
Classification: G06F,G11C,H01L,Y02D

Abstract:
1. A storage element comprising: a first storage circuit; a second storage circuit comprising: wherein the first storage circuit holds data only in a period during which a power supply voltage is supplied, wherein the first transistor comprises a channel provided in an oxide semiconductor layer, wherein one of the first source and the first drain is electrically connected to one of the pair of first electrodes and the second gate, wherein one of the second source and the second drain is electrically connected to a first power supply line, wherein the other of the second source and the second drain is electrically connected to the first terminal, wherein the second terminal is electrically connected to the third terminal, wherein the fourth terminal is electrically connected to a second power supply line, wherein a first control signal is input to the first gate, wherein a conduction state or a non-conduction state in each of the first switch and the second switch is selected by a second control signal which is different from the first control signal, wherein when one of the first switch and the second switch is in a conduction state, the other of the first switch and the second switch is in a non-conduction state, wherein a conduction state or a non-conduction state in the third switch is selected by a third control signal which is different from the first control signal and the second control signal, wherein a signal corresponding to data held in the first storage circuit is input to the other of the first source and the first drain, and wherein a signal output from the second terminal or an inverted signal of the signal output from the second terminal is input to the first storage circuit through the third switch.