Image sensor with feedthrough-compensated charge-binned readout
AssigneeRambus Inc.
InventorMichael Guidash
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Abstract
In an integrated-circuit image sensor having a pixel array, first and second control pulses that enable photocharge transfer from respective first and second photosensitive elements to a shared floating diffusion node are staggered in time such that capacitive feedthrough to the shared floating diffusion node from a trailing edge of the first control pulse is counteracted by capacitive feedthrough to the shared floating diffusion node from a leading edge of the second control pulse.
Claims21
A method of operation within an integrated-circuit image sensor having a pixel array, the method comprising:
- generating a first control pulse on a first signal line connected to a first pixel within the pixel array to enable photocharge accumulated within a photosensitive element of the first pixel to be transferred to a shared floating diffusion node;
- and
- generating a second control pulse on a second signal line connected to a second pixel within the pixel array to enable photocharge accumulated within a photosensitive element of the second pixel to be transferred to the shared floating diffusion node and combined therein with the photocharge transferred from the photosensitive element of the first pixel, the first and second control pulses being staggered in time such that capacitive feedthrough to the shared floating diffusion node from a trailing edge of the first control pulse is counteracted by capacitive feedthrough to the shared floating diffusion node from a leading edge of the second control pulse.
An integrated-circuit image sensor comprising:
- a pixel array including first and second pixels coupled to first and second signal lines, respectively, the first and second pixels having respective photosensitive elements and a shared floating diffusion node;
- and
- control circuitry to generate first and second control pulses on the first and second signal lines, respectively, to enable photocharge accumulated within the photosensitive elements of the first and second pixels to be transferred to, and combined within, the shared floating diffusion node, the first control pulse being time-staggered relative to the second control pulse such that capacitive feedthrough to the shared floating diffusion node from a trailing edge of the first control pulse is counteracted by capacitive feedthrough to the shared floating diffusion node from a leading edge of the second control pulse.
An integrated-circuit image sensor comprising:
- a pixel array including first and second pixels coupled to first and second signal lines, respectively, the first and second pixels having respective photosensitive elements and a shared floating diffusion node;
- and
- means for generating first and second control pulses on the first and second signal lines, respectively, to enable photocharge accumulated within the photosensitive elements of the first and second pixels to be transferred to, and combined within, the shared floating diffusion node, the first control pulse being time-staggered relative to the second control pulse such that capacitive feedthrough to the shared floating diffusion node from a trailing edge of the first control pulse is counteracted by capacitive feedthrough to the shared floating diffusion node from a leading edge of the second control pulse.
Dependencies are inferred from the claim text.