Image sensors with anti-eclipse circuitry

Abstract

An image sensor may include an array of image pixels arranged in rows and columns. Image pixels arranged along the same column may be coupled to a column line. The column line may be coupled to anti-eclipse control circuitry. In one suitable arrangement, the anti-eclipse control circuitry may include a comparator that compares the output signal on the column line to an anti-eclipse bias voltage. If, during a reset sampling period, the output signal on the column line is less than the anti-eclipse bias voltage, a transistor may be asserted that couples the floating diffusion region in the pixel to a power supply terminal. Using this arrangement, at least a minimum pixel level may be output when the eclipse condition is met and noise from the reset sample will correlated to noise in the incident light sample.