Analog reference voltage generator, method thereof, analog-to-digital converter including the same, and image sensor including the same

摘要

An analog reference voltage generator for generating a monotonously increasing or decreasing analog reference voltage includes a plurality of dump cells in front of an operational amplifier and controls the dump cells using a plurality of clock signals, respectively, which do not overlap each other in time, thereby increasing a ramping speed. The analog reference voltage generator including the plurality of dump cells controls the generation of an analog reference voltage using the plurality of clock signals obtained by dividing a master clock signal, thereby preventing the voltage level of the reference signal from decreasing due to an increase of the load.