Electronic shutter control in image sensors
View Patent ↗An image sensor includes an electronic shutter layer that is used to drain charge during an electronic shutter operation. A timing generator is electrically connected to a selector component. The selector component is electrically connected to an electronic shutter pulse driver component. The electronic shutter pulse driver component is electrically connected to a current sensing component. The current sensing component is electrically connected to the electronic shutter layer through a contact. The current sensing component senses a current level in the electronic shutter layer and changes a state of an alert signal when the current level equals or exceeds a threshold current level. Depending on the state of an alert signal, the selector component either transmits, or does not transmit, the drive pulse signal to the electronic shutter pulse driver component. An electronic shutter operation is performed when the electronic shutter pulse driver component receives the drive pulse signal.
1. An image sensor, comprising:
a contact to an electronic shutter layer;
a current sensing component electrically connected to the contact, wherein the current sensing component changes a state of an alert signal from a first state to a second state when a current level in the electronic shutter layer exceeds a threshold current level;
a selector component that receives the alert signal and a drive pulse signal; and
an electronic shutter pulse driver component electrically connected to an output of the selector component, wherein the selector component transmits the drive pulse signal to the electronic shutter pulse driver component when the alert signal is at the first state and does not transmit the drive pulse signal to the electronic shutter pulse driver component when the alert signal is at the second state.
2. The image sensor as in claim 1 , wherein the selector component comprises a switch.
3. The image sensor as in claim 1 , wherein the selector component comprises a logic gate.
4. The image sensor as in claim 3 , wherein the logic gate comprises an OR gate.
5. An image capture device, comprising:
an image sensor including an electronic shutter layer;
a contact to the electronic shutter layer;
a current sensing component electrically connected to the contact, wherein the current sensing component changes a state of an alert signal from a first state to a second state when a current level in the electronic shutter layer exceeds a threshold current level;
a timing generator that produces a drive pulse signal when an electronic shutter operation is to be performed;
a selector component that receives the drive pulse signal and the alert signal; and
an electronic shutter pulse driver component electrically connected to an output of the selector component, wherein the selector component transmits the drive pulse signal to the electronic shutter pulse driver component when the alert signal is at the first state and does not transmit the drive pulse signal to the electronic shutter pulse driver component when the alert signal is at the second state.
6. The image capture device as in claim 5 , wherein the current sensing component is included in the image sensor.
7. The image capture device as in claim 5 , wherein the electronic shutter pulse driver component is included in the image sensor.
8. The image capture device as in claim 5 , wherein the selector component is included in the image sensor.
9. The image capture device as in claim 5 , wherein the selector component comprises a switch.
10. The image capture device as in claim 5 , wherein the selector component comprises a logic gate.
11. The image capture device as in claim 10 , wherein the logic gate comprises an OR gate.