Image sensor and imaging device
An imaging device having first and second pixels is described. The first pixel includes a first transfer transistor, a first reset transistor, a first amplifier transistor and a first select transistor. The second pixel includes a first photoelectric conversion element, a second transfer transistor, a second reset transistor, a second amplifier transistor and a second select transistor.
1. An imaging device comprising:
a pixel including:
a first photoelectric conversion element;
a first transfer transistor, wherein a first terminal of the first transfer transistor is coupled to the first photoelectric conversion element;
a first amplifier transistor, wherein a gate of the first amplifier transistor is coupled to a second terminal of the first transfer transistor and wherein a first terminal of the first amplifier transistor is coupled to a power line; and
a first reset transistor, wherein a first terminal of the first reset transistor is coupled to the second terminal of the first transfer transistor and wherein a second terminal of the first reset transistor is coupled to the power line;
a test signal generator including:
a second transfer transistor having a first terminal and a second terminal;
a second amplifier transistor, wherein a gate of the second amplifier transistor is coupled to the second terminal of the second transfer transistor and wherein a first terminal of the second amplifier transistor is coupled to the power line; and
a second reset transistor, wherein a first terminal of the second reset transistor is coupled to the second terminal of the second transfer transistor and wherein a second terminal of the second reset transistor is coupled to a test voltage generation circuit which is separated from the power line;
a reset control signal line coupled to a gate of the first reset transistor in the pixel and a gate of the second reset transistor in the test signal generator;
a vertical scanning unit coupled to the reset control signal line.
2. The imaging device according to claim 1 , wherein the second terminal of the second reset transistor is not coupled to the power line.
3. The imaging device according to claim 1 , wherein the first terminal of the second transfer transistor is coupled to the test voltage generation circuit.
4. The imaging device according to claim 1 , wherein the test signal generator does not include a photoelectric conversion element.
5. The imaging device according to claim 1 , wherein a pixel region including the pixel is disposed between first and second test signal generator regions including the test signal generator in a pixel array.
6. The imaging device according to claim 1 , wherein the vertical scanning unit is configured to generate a reset control signal and output the reset control signal through the reset control signal line.
7. The imaging device according to claim 1 , further comprising a failure detector coupled to a second terminal of the second amplifier transistor via a second select transistor and an analog-to-digital conversion element, wherein the failure detector comprises at least one comparison element.
8. The imaging device according to claim 7 , wherein the failure detector is configured to detect a failure of the reset control signal line.
9. The imaging device according to claim 1 , wherein the imaging device is mounted on a vehicle.
10. An imaging device comprising:
a first chip including:
a pixel including:
a first photoelectric conversion element;
a first transfer transistor, wherein a first terminal of the first transfer transistor is coupled to the first photoelectric conversion element;
a first amplifier transistor, wherein a gate of the first amplifier transistor is coupled to a second terminal of the first transfer transistor and wherein a first terminal of the first amplifier transistor is coupled to a power line; and
a first reset transistor, wherein a first terminal of the first reset transistor is coupled to the second terminal of the first transfer transistor and wherein a second terminal of the first reset transistor is coupled to the power line;
a test signal generator including:
a second transfer transistor having a first terminal and a second terminal;
a second amplifier transistor, wherein a gate of the second amplifier transistor is coupled to the second terminal of the second transfer transistor and wherein a first terminal of the second amplifier transistor is coupled to the power line; and
a second reset transistor, wherein a first terminal of the second reset transistor is coupled to the second terminal of the second transfer transistor and wherein a second terminal of the second reset transistor is coupled to a test voltage generation circuit which is separated from the power line; and
a reset control signal line coupled to the pixel and the test signal generator; and
a second chip including:
a vertical scanning unit coupled to the reset control signal line via a first inter-chip connection terminal.
11. The imaging device according to claim 10 , wherein the second terminal of the second reset transistor is not coupled to the power line.
12. The imaging device according to claim 10 , wherein the first terminal of the second transfer transistor is coupled to the test voltage generation circuit.
13. The imaging device according to claim 10 , wherein the test signal generator does not include a photoelectric conversion element.
14. The imaging device according to claim 10 , wherein a pixel region including the pixel is disposed between first and second test signal generator regions including the test signal generator in a pixel array.
15. The imaging device according to claim 10 , wherein the vertical scanning unit is configured to generate a reset control signal and output the reset control signal through the reset control signal line.
16. The imaging device according to claim 10 , further comprising a failure detector coupled to a second terminal of the second amplifier transistor via a second select transistor and an analog-to-digital conversion element, wherein the failure detector comprises at least one comparison element.
17. The imaging device according to claim 16 , wherein the failure detector is configured to detect a failure of the reset control signal line.
18. The imaging device according to claim 10 , wherein the imaging device is mounted on a vehicle.
19. The imaging device according to claim 10 , wherein the first transfer transistor has a gate configured to receive a transfer enabling signal on a transfer control signal line.
20. The imaging device according to claim 19 , wherein the gate of the first amplifier transistor is configured to receive a signal from the first transfer transistor based on an electric charge generated by the first photoelectric conversion element.