ADC FOR A/D CONVERSION USING COMPLEMENTARY RAMP SIGNAL AND IMAGE SENSING DEVICE USING THE SAME

摘要

PURPOSE: An analog to digital converter (ADC) for outputting a digitized sample signal after comparing a sample signal and a ramp signal and an image sensing apparatus applying the same are provided to increase an analog to digital (A/D) conversion speed two times faster than when exclusively using an existing up-ramp, thereby providing a high-definition image without delay. CONSTITUTION: A pixel (110) outputs an analog pixel value. A sample and hold (S/H) amplifier (120) generates a sample signal by performing a sample-and-hold operation of the analog pixel value outputted from the pixel. An ADC (130) digitizes the sample signal generated in the S/H amplifier after comparing the sample signal and multiple ramp signals. [Reference numerals] (110) Pixel; (131) Comparator-1; (132) Comparator-2; (133) Memory; (135) Compensation converter; (141) Up-lamp signal generator; (142) Down-lamp signal generator; (150) Counter