Semiconductor device and driving method thereof

1. A semiconductor device comprising:

a transistor;

a first switch;

a second switch; and

a first capacitor,

wherein a first terminal of the capacitor is electrically connected to a gate of the transistor,

wherein a first potential is supplied to the gate of the transistor through the first switch,

wherein a second potential is supplied to a second terminal of the first capacitor through the second switch, and

wherein a first capacitance value of the first capacitor is equal to a gate capacitance value of the transistor.

2. The semiconductor device according to claim 1 , wherein the first switch and the second switch are transistors each including an oxide semiconductor in a channel formation region.

3. The semiconductor device according to claim 1 ,

wherein the first switch is positioned over the transistor, and

wherein the second switch is positioned over the first switch.

4. The semiconductor device according to claim 1 ,

wherein the first switch and the second switch are transistors each including an oxide semiconductor in a channel formation region,

wherein the first switch is positioned over the transistor, and

wherein the second switch is positioned over the first switch.

5. The semiconductor device according to claim 1 , further comprising a second capacitor,

wherein a first terminal of the second capacitor is electrically connected to the gate of the transistor, and

wherein a third potential is supplied to a second terminal of the second capacitor.

6. An electronic device comprising:

the semiconductor device according to claim 1 ; and

at least one of a microphone, a speaker, a display portion, and an operation key.

7. A semiconductor device comprising:

a transistor;

a first switch;

a second switch; and

a first capacitor,

wherein a first terminal of the capacitor is electrically connected to a gate of the transistor,

wherein a first potential is supplied to the gate of the transistor through the first switch,

wherein a second potential is supplied to a second terminal of the first capacitor through the second switch, and

wherein an absolute value of a difference between a first capacitance value of the first capacitor and a gate capacitance value of the transistor is within 20% of each of the first capacitance value and the gate capacitance value.

8. The semiconductor device according to claim 7 , wherein the first switch and the second switch are transistors each including an oxide semiconductor in a channel formation region.

9. The semiconductor device according to claim 7 ,

wherein the first switch is positioned over the transistor, and

wherein the second switch is positioned over the first switch.

10. The semiconductor device according to claim 7 ,

wherein the first switch and the second switch are transistors each including an oxide semiconductor in a channel formation region,

wherein the first switch is positioned over the transistor, and

wherein the second switch is positioned over the first switch.

11. The semiconductor device according to claim 7 , further comprising a second capacitor,

wherein a first terminal of the second capacitor is electrically connected to the gate of the transistor,

wherein a third potential is supplied to a second terminal of the second capacitor, and

wherein an absolute value of a difference between the first capacitance value and a sum of the gate capacitance value of the transistor and a second capacitance value of the second capacitor is within 20% of each of the first capacitance value and the sum.

12. An electronic device comprising:

the semiconductor device according to claim 7 ; and

at least one of a microphone, a speaker, a display portion, and an operation key.

13. A semiconductor device comprising:

a transistor;

first to N-th switches; and

first to (N−1)-th capacitors,

wherein N is a natural number of three or more,

wherein a first terminal of the first capacitor is electrically connected to a gate of the transistor,

wherein a first terminal of a J-th capacitor is electrically connected to a second terminal of a (J−1)-th capacitor,

wherein J is a natural number of two or more and (N−1) or less,

wherein a first potential is supplied to the gate of the transistor through the first switch,

wherein a K-th potential is supplied to a second terminal of a (K−1)-th capacitor through a K-th switch,

wherein K is a natural number of two or more and N or less,

wherein a first capacitance value of the first capacitor is equal to a gate capacitance value of the transistor, and

wherein a second capacitance value of the J-th capacitor is equal to a third capacitance value of the (J−1)-th capacitor.

14. The semiconductor device according to claim 13 , further comprising an N-th capacitor,

wherein a first terminal of the N-th capacitor is electrically connected to the gate of the transistor, and

wherein an (N+1)-th potential is supplied to a second terminal of the N-th capacitor.

15. The semiconductor device according to claim 13 , wherein the first to N-th switches are transistors each including an oxide semiconductor in a channel formation region.

16. The semiconductor device according to claim 13 ,

wherein the first switch is positioned over the transistor, and

wherein the K-th switch is positioned over the (K−1)-th switch.

17. The semiconductor device according to claim 13 ,

wherein the first to N-th switches are transistors each including an oxide semiconductor in a channel formation region,

wherein the first switch is positioned over the transistor, and

wherein the K-th switch is positioned over the (K−1)-th switch.

18. An electronic device comprising:

the semiconductor device according to claim 13 ; and

at least one of a microphone, a speaker, a display portion, and an operation key.