RAMP-SIGNAL GENERATOR CIRCUIT, AND IMAGE SENSOR AND IMAGING SYSTEM INCLUDING THE SAME

摘要

The ramp-signal generator circuit includes a reference voltage generator that changes the voltage of a reference signal Vr to a comparator setting voltage VR for compensating for a voltage difference between a reference signal Vr and an analog input signal (Vs1-Vsn) before comparison by an analog-to-digital converter circuit and outputs a ramp signal whose slope starts from the comparator setting voltage VR in response to a start of the comparison. The ramp-signal generator circuit is configured to add a predetermined enhanced voltage VA to the comparator setting voltage VR before the comparison.