< BK21 플러스 BEST 정보기술 사업단 세미나 개최 안내 >

개최일시 : 2015년 8월 5일 수요일 16:00 ~ 18:00

개최장소 :  제3공학관 C616호

세미나 제목 : Low Power ADC Design with Ring Amplifiers

발표초록 : 

The ring amplifier is an energy efficient and high output swing alternative to an OTA for switched-capacitor circuits. However, the conventional ring amplifier requires external biases, which makes the ring amplifier less practical when we consider process, supply voltage, and temperature (PVT) variation. In this talk, two types of improved ring amplifiers are presented which overcome the limitations of the conventional ring amplifier.

The first one is a self-biased ring amplifier scheme that makes the ring amplifier more practical and power efficient while maintaining the benefits of efficient slew-based charging and an almost rail-to-rail output swing. The prototype 10.5b pipeline ADC with the self-biased ring amplifiers has measured SNDR, SNR and SFDR of 56.6 dB (9.11b), 57.5 dB and 64.7 dB, respectively, for a Nyquist frequency input sampled at 100 MS/s, and consumes 2.46 mW.

The second one is a fully differential ring amplifier, which solves the problems of single-ended ring amplifiers while maintaining the benefits of the single ended ring amplifiers. The prototype 13b SAR-assisted pipeline ADC with fully differential ring amplifier achieves measured SNDR, SNR and SFDR of 70.9 dB (11.5b), 71.3 dB and 84.6 dB, respectively, with a Nyquist frequency input sampled at 50 MS/s, and consumes 1 mW. This measured performance is equivalent to Walden and Schreier FoMs of 6.9 fJ/conversion∙step and 174.9 dB, respectively.

강연자 : Yong Lim (Ph.D Candidate) / University of Michigan, Ann Arbor

초청자 : 전기전자공학과 교수 채영철