Semiconductor device and driving method thereof

A semiconductor device comprising:

• a photodiode;
• a first transistor;
• a second transistor;
• and
• a third transistor,
• wherein a first terminal of the photodiode is electrically connected to a first terminal of the second transistor,
• wherein a second terminal of the second transistor is electrically connected to a gate of the first transistor and a first terminal of the third transistor,
• wherein in a first period, a charge corresponding to an amount of incident light to the photodiode is accumulated to the gate of the first transistor,
• wherein in a second period, the charge is retained in the gate of the first transistor while a first voltage is supplied to a gate of the second transistor and a second voltage is supplied to a gate of the third transistor, and
• wherein a voltage level of the first voltage is lower than a voltage level of the first terminal of the second transistor and a voltage level of the second terminal of the second transistor, and a voltage level of the second voltage is lower than a voltage level of the first terminal of the third transistor and a voltage level of a second terminal of the third transistor.

A semiconductor device comprising:

• a photodiode;
• a first transistor;
• and
• a second transistor;
• wherein a first terminal of the photodiode is electrically connected to a first terminal of the second transistor,
• wherein a second terminal of the second transistor is electrically connected to a gate of the first transistor,
• wherein in a first period, a charge corresponding to an amount of incident light to the photodiode is accumulated to the gate of the first transistor,
• wherein in a second period, the charge is retained in the gate of the first transistor while a first voltage is supplied to a gate of the second transistor, and
• wherein a voltage level of the first voltage is lower than a voltage level of the first terminal of the second transistor and a voltage level of the second terminal of the second transistor.

A driving method of a semiconductor device comprising:

• accumulating a charge to a gate of a first transistor by supplying a first voltage to a first terminal of a photodiode, a second voltage to a gate of a second transistor, and a third voltage to a gate of a third transistor,
• retaining the charge in the gate of the first transistor by supplying a fourth voltage to the gate of the second transistor and a fifth voltage to the gate of the third transistor, and
• discharging the charge from the gate of the first transistor by supplying a sixth voltage to the gate of the third transistor and a seventh voltage to a first terminal of the third transistor,
• wherein the charge corresponds to an amount of incident light to the photodiode, and
• wherein a voltage level of the fourth voltage is lower than a voltage level of a first terminal of the second transistor and a voltage level of a second terminal of the second transistor, and a voltage level of the fifth voltage is lower than a voltage level of the first terminal of the third transistor and a voltage level of a second terminal of the third transistor in retaining.

A driving method of a semiconductor device comprising:

• accumulating a charge to a gate of a first transistor by supplying a first voltage to a first terminal of a photodiode, and a second voltage to a gate of a second transistor,
• retaining the charge in the gate of the first transistor by supplying a third voltage to the gate of the second transistor, and
• discharging the charge from the gate of the first transistor by supplying a fourth voltage to the gate of the second transistor and a fifth voltage to the first terminal of the photodiode,
• wherein the charge corresponds to an amount of incident light to the photodiode, and
• wherein a voltage level of the third voltage is lower than a voltage level of a first terminal of the second transistor and a voltage level of a second terminal of the second transistor in retaining.