Imaging device comprising current mirror circuit

Patent metadata

Field	Value
Publication number	US-10964743-B2
Application number	US-202016822330-A
Country	US
Kind code	B2
Filing date	Mar 18, 2020
Priority date	Dec 10, 2014
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

A semiconductor device including pixels arranged in a matrix of n rows and m columns, in which the pixels in the m-th column are shielded from light, is provided.

First claim

What is claimed is:

1. An imaging device comprising:
a first pixel;
a second pixel; and
a current mirror circuit,
wherein a first current corresponding to a current flowing through the first pixel flows to an input transistor of the current mirror circuit,
wherein a second current flows to an output transistor of the current mirror circuit, and
wherein a difference between the second current and a third current corresponding to a current flowing through the second pixel is calculated.

2. The imaging device according to claim 1 , wherein current value of the second current is the same as current value of the first current.

3. The imaging device according to claim 1 , wherein the current flowing through the first pixel is a current corresponding to a state in which a charge retention portion included in the first pixel is initialized.

4. An imaging device comprising:
a first pixel;
a second pixel; and
a current mirror circuit,
wherein a first current corresponding to a current flowing through the first pixel flows to an input transistor of the current mirror circuit,
wherein a second current flows to an output transistor of the current mirror circuit,
wherein a difference between the second current and a third current corresponding to a current flowing through the second pixel is calculated,
wherein each the input transistor and the output transistor is a p-channel transistor, and
wherein each of the first pixel and the second pixel includes an n-channel transistor.

5. The imaging device according to claim 4 , wherein current value of the second current is the same as current value of the first current.

6. The imaging device according to claim 4 , wherein the current flowing through the first pixel is a current corresponding to a state in which a charge retention portion included in the first pixel is initialized.

7. An imaging device comprising:
a first pixel;
a second pixel; and
a current mirror circuit,
wherein a first current corresponding to a current flowing through the first pixel flows to an input transistor of the current mirror circuit,
wherein a light-blocking layer is arranged at a side where light enters a photoelectric conversion element included in the first pixel,
wherein a second current flows to an output transistor of the current mirror circuit, and
wherein a difference between the second current and a third current corresponding to a current flowing through the second pixel is calculated.

8. The imaging device according to claim 7 , wherein current value of the second current is the same as current value of the first current.

9. The imaging device according to claim 7 , wherein the current flowing through the first pixel is a current corresponding to a state in which a charge retention portion included in the first pixel is initialized.

10. The imaging device according to claim 7 ,
wherein each the input transistor and the output transistor is a p-channel transistor,
wherein each of the first pixel and the second pixel includes an n-channel transistor.

Assignees

• Semiconductor Energy Lab

Inventors

• Kurokawa Yoshiyuki

Classifications

• H10D62/80

  characterised by the materials · CPC title

• H10F77/126

  comprising only Group I-III-VI chalcopyrite materials, e.g. CuInSe2, CuGaSe2 or CuInGaSe2 [CIGS] · CPC title

• H10F77/121

  comprising only selenium or only tellurium · CPC title

• H10F39/8057

  Optical shielding · CPC title

• H10F39/8037

  the integrated elements comprising a transistor · CPC title