Image sensor with increased dynamic range
AssigneeCommissariat à I'Énergie Atomique et aux Énergies Alternatives
InventorFrançois Ayel
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Abstract
An image sensor including: a pixel circuit comprising a first transistor having one of its main conducting nodes connected to an output line, the other of its main conducting nodes coupled to a supply voltage rail via a read transistor, and its control node coupled to a sense node of the pixel circuit; a current source coupled to the output line; and a control circuit configured to read a pixel voltage from the pixel circuit by: activating the current source while the read transistor is non-conducting; and deactivating the current source and activating the read transistor of the pixel circuit in order to impose a boosted voltage at the sense node.
Claims12
An image sensor comprising:
- a pixel circuit comprising a first transistor having one of its main conducting nodes connected to an output line, the other of its main conducting nodes coupled to a supply voltage rail via a read transistor, and its control node coupled to a sense node of the pixel circuit;
- a current source coupled to the output line;
- and
- a control circuit configured to read a pixel voltage from the pixel circuit by:
- activating the current source while the read transistor is non-conducting;
- and
- deactivating the current source and activating the read transistor while the current source remains deactivated in order to impose a boosted voltage at the sense node.
A method of reading a pixel voltage from a pixel circuit of an image sensor, the pixel circuit comprising a first transistor having one of its main conducting nodes connected to an output line, the other of its main conducting nodes coupled to a supply voltage rail via a read transistor, and its control node coupled to a sense node of the pixel circuit, the method comprising:
- activating a current source of the image sensor coupled to the output line while the read transistor is non-conducting;
- and
- deactivating the current source and activating the read transistor while the current source remains deactivated in order to impose a boosted voltage at the sense node.
Dependencies are inferred from the claim text.