A 2 V, 10 B, 20 MSAMPLE S, MIXED-MODE SUBRANGING CMOS A/D CONVERTER/

We have developed a 2 V, 10 b, 20 MS/s, mixed-mode (voltage-mode and c urrent-mode) subranging CMOS A/D Converter (ADC) suitable for video-si gnal processing systems, Its 2 V supply voltage and 20 mW power consum ption are lower than those of any other video-rate ADC reported to dat e, This ADC employs voltage-mode circuitry for coarse 5 b A/D conversi on and current-mode circuitry for fine 6 b A/D conversion, In addition to this mixed-mode subranging architecture, a newly developed differe ntial comparator and a new current-tree A/D conversion architecture al so contribute to the achievement of high speed at low supply voltage.