Patent ID: 8735795

Claim:
An image sensor, comprising: a pixel array including a plurality of pixel cells organized into rows and columns, the pixel array for capturing image data and ambient light data; readout circuitry coupled via column bit lines to the pixels cells to read out the image data along the column bit lines; an ambient light detection (“ALD”) unit selectively coupled to the pixel array to readout the ambient light data and to generate an ambient light signal based on ambient light incident upon the pixel array; control circuitry coupled to the pixel array to control time sharing of the pixels cells between the readout circuitry during an image acquisition mode of operation of the image sensor and the ALD unit during an ambient light sensing mode of operation of the image sensor; local sensing lines each coupled to a corresponding group of the pixel cells to combine the ambient light data from the corresponding group of the pixels cells; a global sensing line coupled to the ALD unit and selectively coupled to the local sensing lines for combining the ambient light data received from the local sensing lines; and a plurality of switches each coupled between the global sensing line and a corresponding one of the local sensing lines, wherein the control circuitry is coupled to control the switches.