Patent attributes
An image sensor includes a plurality of pixel columns and a plurality of readout circuits. Each readout circuit is coupled to one of the plurality of pixel columns and includes an ADC for receiving a first analog signal of a pixel in a reset conversion phase and a second analog signal of the pixel in a signal measurement phase, a dual-ramp generator for generating a first ramp having a first ramp rate and a second ramp having a second ramp rate greater than the first ramp rate and providing the first ramp to the readout circuits in the reset conversion phase and the second ramp to the plurality of readout circuits in the signal measurement phase, and a controller configured to provide control signals to the readout circuits and the dual-ramp generator.