Photoelectric conversion device, photoelectric conversion system, and moving body
A photoelectric conversion device includes a photoelectric converter, a first node configured to be supplied with charges from the photoelectric converter, an amplification transistor configured to output a signal corresponding to a voltage of the first node, a first transistor configured to open/close a path between the first node and a second node not included in a path from the photoelectric converter to the first node, and a second transistor configured to open/close a path between the second node and a third node. A second capacitance which is added to the second node when the second transistor is set in a conductive state is larger than a first capacitance which is added to the first node when the first transistor is set in a conductive state.
1. A photoelectric conversion device comprising:
a photoelectric converter;
a first node configured to be supplied with charges from the photoelectric converter;
an amplification transistor configured to output a signal corresponding to a voltage of the first node;
a first transistor configured to open/close a path between the first node and a second node not included in a path from the photoelectric converter to the first node; and
a second transistor configured to open/close a path between the second node and a third node,
wherein a gate length of the second transistor is longer than a gate length of the first transistor.
2. The device according to claim 1 , wherein a gate width of the second transistor is equal to a gate width of the first transistor.
3. The device according to claim 1 , wherein a channel length direction of the first transistor and the second transistor is parallel to one side of the photoelectric converter.
4. The device according to claim 1 , wherein the first transistor, the second transistor, and a third transistor are arranged in a first active region, and
wherein the amplification transistor is arranged in a second active region.
5. The device according to claim 4 , wherein the selection transistor is arranged in the second active region.
6. The device according to claim 1 , wherein a second capacitance which is added to the second node when the second transistor is set in a conductive state is larger than a first capacitance which is added to the first node when the first transistor is set in a conductive state.
7. The device according to claim 1 , wherein a third capacitance which is added to the third node when a third transistor is set in a conductive state is larger than the second capacitance which is added to the second node when the second transistor is set in a conductive state.
8. The device according to claim 1 , wherein a difference between a gate width of the first transistor and a gate width of the second transistor is smaller than a difference between a gate length of the first transistor and a gate length of the second transistor.
9. A photoelectric conversion system comprising:
the photoelectric conversion device according to claim 1 ; and
a signal processor configured to process a signal output from the photoelectric conversion device.
10. A moving body comprising:
the photoelectric conversion device according to claim 1 ;
a distance information acquisition unit configured to acquire distance information to a target object from distance measurement information based on a signal from the photoelectric conversion device; and
a control unit configured to control the moving body based on the distance information.
11. A photoelectric conversion device comprising:
a photoelectric converter;
a first node configured to be supplied with charges from the photoelectric converter;
an amplification transistor configured to output a signal corresponding to a voltage of the first node;
a first transistor configured to open/close a path between the first node and a second node not included in a path from the photoelectric converter to the first node;
a second transistor configured to open/close a path between the second node and a third node;
a third transistor arranged in a path between the third node and a fourth node; and
a reset transistor configured to reset a potential of the first node, and to open/close a path between the fourth node and a predetermined voltage line,
wherein a fixed potential that sets the third transistor in a conductive state is applied to a gate of the third transistor from the predetermined voltage line.
12. The device according to claim 11 , wherein a capacitance of the third transistor is larger than a capacitance of the first transistor.
13. The device according to claim 11 , wherein a capacitance of the third transistor is larger than a capacitance of the first node when the first transistor is in a non-conductive state.
14. The device according to claim 11 , wherein a gate width of the second transistor is equal to a gate width of the first transistor.
15. The device according to claim 11 , wherein a difference between a gate width of the first transistor and a gate width of the second transistor is smaller than a difference between a gate length of the first transistor and a gate length of the second transistor.
16. The device according to claim 11 , wherein a channel length direction of the first transistor and the second transistor is parallel to one side of the photoelectric converter.
17. The device according to claim 11 , wherein the first transistor, the second transistor, and the third transistor are arranged in a first active region, and
wherein the amplification transistor is arranged in a second active region.
18. The device according to claim 17 , wherein the selection transistor is arranged in the second active region.
19. A photoelectric conversion system comprising:
the photoelectric conversion device according to claim 11 ; and
a signal processor configured to process a signal output from the photoelectric conversion device.
20. A moving body comprising:
the photoelectric conversion device according to claim 11 ;
a distance information acquisition unit configured to acquire distance information to a target object from distance measurement information based on a signal from the photoelectric conversion device; and
a control unit configured to control the moving body based on the distance information.
21. A photoelectric conversion device comprising:
a photoelectric converter;
a first node configured to be supplied with charges from the photoelectric converter;
an amplification transistor configured to output a signal corresponding to a voltage of the first node;
a first transistor configured to open/close a path between the first node and a second node not included in a path from the photoelectric converter to the first node;
a second transistor configured to open/close a path between the second node and a third node;
a third transistor arranged in a path between the third node and a fourth node; and
a reset transistor configured to reset a potential of the first node, and to open/close a path between the fourth node and a predetermined voltage line,
wherein a predetermined voltage line is connected to a gate of the third transistor.
22. The device according to claim 21 , wherein a capacitance of the third transistor is larger than a capacitance of the first transistor.
23. The device according to claim 21 , wherein a capacitance of the third transistor is larger than a capacitance of the first node when the first transistor is in a non-conductive state.
24. The device according to claim 21 , wherein a gate width of the second transistor is equal to a gate width of the first transistor.
25. The device according to claim 21 , wherein a difference between a gate width of the first transistor and a gate width of the second transistor is smaller than a difference between a gate length of the first transistor and a gate length of the second transistor.
26. A photoelectric conversion system comprising:
the photoelectric conversion device according to claim 21 ; and
a signal processor configured to process a signal output from the photoelectric conversion device.
27. A moving body comprising:
the photoelectric conversion device according to claim 21 ;
a distance information acquisition unit configured to acquire distance information to a target object from distance measurement information based on a signal from the photoelectric conversion device; and
a control unit configured to control the moving body based on the distance information.