Patent ID: 8208283

Claim:
A data holding device comprising: a loop structure portion for holding data by using a plurality of logic gates connected like a loop; a nonvolatile storage portion for storing data held in the loop structure portion, in a nonvolatile manner by using a hysteresis characteristic of a ferroelectric element; and a circuit separating portion for electrically separating the loop structure portion and the nonvolatile storage portion from each other, wherein the loop structure portion and the nonvolatile storage portion are driven by being respectively supplied with first and second power supply voltages that are different from each other, the circuit separating portion includes a level shifter for converting a voltage level of the data communicated between the loop structure portion and the nonvolatile storage portion, the second power supply voltage that is supplied to the nonvolatile storage portion is higher than the first power supply voltage that is supplied to the loop structure portion, and the circuit separating portion makes the loop structure portion operate electrically while maintaining an applied voltage to the ferroelectric element to be constant during a normal operation of the data holding device.