Photoelectric conversion device and electronic device
A photoelectric conversion device capable of operations corresponding to the amplitude of a signal read out to a vertical signal line is disclosed. The device comprises a pixel that generates a signal via photoelectric conversion and a determination circuit that determines an amplitude of a signal read out from the pixel to a vertical signal line. A reset signal and a data signal are read out from the pixel. The determination circuit performs a first determination on the data signal while the pixel is being selected for reading out a signal and performs a second determination on the reset signal.
1. A photoelectric conversion device, comprising:
a pixel that generates a signal via photoelectric conversion, wherein from the pixel, a reset signal and a data signal are read out; and
a determination circuit that determines an amplitude of a signal read out from the pixel to a vertical signal line,
wherein the determination circuit performs a first determination on the data signal while the pixel is being selected for reading out a signal and performs a second determination on the reset signal,
wherein the determination circuit is driven by a current source connected to the vertical signal line of the pixel, and
wherein the determination circuit includes a holding circuit that holds an electric potential of a reset signal read out to the vertical signal line and determines an amplitude of the signal using a reference value from which an electric potential of the reset signal held by the holding circuit has been subtracted.
2. The photoelectric conversion device according to claim 1 , further comprising:
an analog-to-digital (A/D) conversion circuit that converts a signal based on either or both of the reset signal and the data signal into a corresponding digital signal.
3. The photoelectric conversion device according to claim 1 , wherein the determination circuit performs the first determination in a first period and performs the second determination in a second period.
4. The photoelectric conversion device according to claim 3 , wherein the determination circuit includes a first determinator that performs the first determination and a second determinator that performs the second determination.
5. The photoelectric conversion device according to claim 1 , wherein the determination circuit uses a first reference value in the first determination and uses a second reference value in the second determination.
6. The photoelectric conversion device according to claim 1 , wherein the determination circuit uses an identical reference value in the first determination and the second determination.
7. The photoelectric conversion device according to claim 6 , wherein a result of the first determination is used by the photoelectric conversion device, and a result of the second determination is output outside of the photoelectric conversion device.
8. The photoelectric conversion device according to claim 1 , wherein the determination circuit is an auto-zero differential amplifier with a function that takes the signal and a reference value for determination of an amplitude of the signal as input and cancels input offset.
9. The photoelectric conversion device according to claim 1 , wherein the determination circuit holds a result of the determination of an amplitude of the signal with the result being readable from outside of the determination circuit.
10. The photoelectric conversion device according to claim 2 , wherein the determination of an amplitude of the signal includes determination for adjusting an analog gain applied to the signal and a digital gain applied to the digital signal output from the A/D conversion circuit.
11. The photoelectric conversion device according to claim 1 , wherein the determination of an amplitude of the signal includes determining whether or not the pixel is blackened.
12. An electronic device, comprising:
a photoelectric conversion device; and
a control apparatus that controls operations of the photoelectric conversion device,
wherein the photoelectric conversion device comprises:
(1) a pixel that generates a signal via photoelectric conversion, wherein from the pixel, a reset signal and a data signal are read out; and
(2) a determination circuit that determines an amplitude of a signal read out from the pixel to a vertical signal line,
wherein the determination circuit performs a first determination on the data signal while the pixel is being selected for reading out a signal and performs a second determination on the reset signal,
wherein the determination circuit is driven by a current source connected to the vertical signal line of the pixel, and
wherein the determination circuit includes a holding circuit that holds an electric potential of a reset signal read out to the vertical signal line and determines an amplitude of the signal using a reference value from which an electric potential of the reset signal held by the holding circuit has been subtracted.
13. A substrate stacked on a substrate provided with a pixel that generates a signal via photoelectric conversion, wherein from the pixel, a reset signal and a data signal are read out, comprising:
a determination circuit that determines an amplitude of a signal read out from the pixel to a vertical signal line,
wherein the determination circuit performs a first determination on the data signal while the pixel is being selected for reading out a signal and performs a second determination on the reset signal,
wherein the determination circuit is driven by a current source connected to the vertical signal line of the pixel, and
wherein the determination circuit includes a holding circuit that holds an electric potential of a reset signal read out to the vertical signal line and determines an amplitude of the signal using a reference value from which an electric potential of the reset signal held by the holding circuit has been subtracted.