Semiconductor device and method for driving the same
First Claim
1. A semiconductor device comprising:
- a plurality of pixels arranged in a matrix, each of the plurality of pixels being electrically connected to first to seventh wirings and comprising;
a photodiode;
a first capacitor;
a second capacitor;
a first transistor;
a second transistor;
a third transistor; and
a data holding portion,wherein a cathode of the photodiode is electrically connected to the first wiring,wherein an anode of the photodiode is electrically connected to a first electrode of the first capacitor,wherein a first electrode of the second capacitor is electrically connected to the third wiring,wherein one of a source and a drain of the first transistor is electrically connected to the second wiring,wherein a gate of the first transistor is electrically connected to the sixth wiring,wherein one of a source and a drain of the second transistor is electrically connected to the fourth wiring,wherein the other of the source and the drain of the second transistor is electrically connected to one of a source and a drain of the third transistor,wherein the other of the source and the drain of the third transistor is electrically connected to the seventh wiring,wherein a gate of the third transistor is electrically connected to the fifth wiring, andwherein the data holding portion is configured by electrically connecting a second electrode of the first capacitor, a second electrode of the second capacitor, the other of the source and the drain of the first transistor, and a gate of the second transistor.
1 Assignment
0 Petitions
Accused Products
Abstract
An image sensor is provided which is capable of holding data for one frame period or longer and conducting a difference operation with a small number of elements. A photosensor is provided in each of a plurality of pixels arranged in a matrix, each pixel accumulates electric charge in a data holding portion for one frame period or longer, and an output of the photosensor changes in accordance with the electric charge accumulated in the data holding portion. As a writing switch element for the data holding portion, a transistor with small leakage current (sufficiently smaller than 1×10−14 A) is used. As an example of the transistor with small leakage current, there is a transistor having a channel formed in an oxide semiconductor layer.
131 Citations
25 Claims
-
1. A semiconductor device comprising:
-
a plurality of pixels arranged in a matrix, each of the plurality of pixels being electrically connected to first to seventh wirings and comprising; a photodiode; a first capacitor; a second capacitor; a first transistor; a second transistor; a third transistor; and a data holding portion, wherein a cathode of the photodiode is electrically connected to the first wiring, wherein an anode of the photodiode is electrically connected to a first electrode of the first capacitor, wherein a first electrode of the second capacitor is electrically connected to the third wiring, wherein one of a source and a drain of the first transistor is electrically connected to the second wiring, wherein a gate of the first transistor is electrically connected to the sixth wiring, wherein one of a source and a drain of the second transistor is electrically connected to the fourth wiring, wherein the other of the source and the drain of the second transistor is electrically connected to one of a source and a drain of the third transistor, wherein the other of the source and the drain of the third transistor is electrically connected to the seventh wiring, wherein a gate of the third transistor is electrically connected to the fifth wiring, and wherein the data holding portion is configured by electrically connecting a second electrode of the first capacitor, a second electrode of the second capacitor, the other of the source and the drain of the first transistor, and a gate of the second transistor. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
2. A semiconductor device comprising:
-
a plurality of pixels arranged in a matrix, each of the plurality of pixels being electrically connected to first to eighth wirings and comprising; a photodiode; a first capacitor; a second capacitor; a first transistor; a second transistor; a third transistor; a fourth transistor; and a data holding portion, wherein a cathode of the photodiode is electrically connected to the first wiring, wherein an anode of the photodiode is electrically connected to one of a source and a drain of the fourth transistor, wherein a gate of the fourth transistor is electrically connected to the eighth wiring, wherein the other of the source and the drain of the fourth transistor is electrically connected to a first electrode of the first capacitor, wherein a first electrode of the second capacitor is electrically connected to the third wiring, wherein one of a source and a drain of the first transistor is electrically connected to the second wiring, wherein a gate of the first transistor is electrically connected to the sixth wiring, wherein one of a source and a drain of the second transistor is electrically connected to the fourth wiring, wherein the other of the source and the drain of the second transistor is electrically connected to one of a source and a drain of the third transistor, wherein the other of the source and the drain of the third transistor is electrically connected to the seventh wiring, wherein a gate of the third transistor is electrically connected to the fifth wiring, and wherein the data holding portion is configured by electrically connecting a second electrode of the first capacitor, a second electrode of the second capacitor, the other of the source and the drain of the first transistor, and a gate of the second transistor. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
-
22. A method for driving a semiconductor device comprising:
-
at least first to third operations in an operation of reading a data holding portion of a photodiode in a pixel, wherein a potential of a first current generated by first light reception by the photodiode is read in the first operation, wherein the potential of the first current from the photodiode is stored in the data holding portion in the second operation, and wherein a combined potential of a potential of a second current generated by second light reception by the photodiode and an output potential based on the potential of the first current stored through the second operation is read in the third operation. - View Dependent Claims (23, 24, 25)
-
Specification