Patent ID: 7486313

Claim:
An analog circuit for performing white balancing using a CMOS sensor, comprising: a first access node that provides a first access voltage to at least a first pixel of a pixel array; at least a second access node that provides a second access voltage to at least a second pixel of the pixel array; a first access switch that operationally couples the first access node to a reset voltage source for making the first access node to receive a reset voltage provided by the reset voltage source directly; a second access switch that operationally couples the second access node to the reset voltage source for making the second access node to receive the reset voltage directly; a first reset switch that controls the pixels in even rows of the pixel array; and a second reset switch that controls the pixels in odd rows of the pixel array, wherein during a measurement phase a change in one of the first access node voltage and the second access voltage provides an average response for a plurality of pixels coupled to the first access node and the second access node; and a pixel averaging operation is performed by pixel charge sharing in a single step instead of processing pixel data sequentially.