Pixel biasing apparatus with noise cancellation function, and cmos image sensor including the same
AssigneeSK hynix Inc.
InventorTae-Hoon Kim
Life of this patent
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Abstract
An image sensor device is provided to include: a pixel bias voltage sampling unit suitable for sampling a pixel bias voltage; a pixel power noise addition control unit suitable for controlling the magnitude of added pixel power noise; a pixel power noise addition unit suitable for adding pixel power noise to a node of the pixel bias voltage sampled by the pixel bias voltage sampling unit according to control of the pixel power noise addition control unit; and a biasing unit suitable for offsetting pixel power noise transmitted from the pixel by inverting the pixel power noise added by the pixel power noise addition unit.
Claims20
An image sensor device, comprising:
- an image sensing pixel that coverts light into a pixel signal;
- and
- a pixel biasing circuit coupled to the image sensing pixel to receive the pixel signal and to supply a bias to the pixel signal to reduce noise in the pixel signal, wherein the pixel biasing circuit includes:
- a pixel bias voltage sampling unit coupled to the image sensing pixel to sample at a circuit node a pixel bias voltage associated with the image sensing pixel;
- a pixel power noise addition unit coupled to the circuit node to add pixel power noise to the circuit node;
- a pixel power noise addition control unit coupled to the pixel power noise additional unit and operable to control a magnitude of added pixel power noise produced by the pixel power noise additional circuit;
- and
- a biasing unit coupled to the image sensing pixel to offset pixel power noise transmitted from the image sensing pixel by inverting the pixel power noise added by the pixel power noise addition unit.
An image sensor device comprising:
- a pixel array including optical sensing pixels, each pixel outputting a pixel signal corresponding to incident light at the pixel;
- a pixel bias voltage supply unit coupled to supply a pixel bias voltage;
- a pixel biasing apparatus coupled to the pixel array and operable to add pixel power noise to a node of the pixel bias voltage, to offset the pixel power noise transmitted from the pixel array by inverting the added pixel power noise;
- and
- a readout processing unit coupled to the pixel biasing apparatus and the pixel array to read out a pixel signal from a pixel in the pixel array.
Dependencies are inferred from the claim text.