부산대학교 도서관

A method for extending the bandwidth limitation of tracking ADCs is presented. It takes advantage of the conventional tracking approach regarding conversion speed. The proposed concept of generating reference steps improves the traditional tracking limits of the input signal slope. MATLAB evaluations of an ideal tracking ADC demonstrate the ability of the novel approach to extend the bandwidth. An implementation in a 65nm process demonstrates the applicability. Verification by post layout simulation results offer an effective resolution of 6.47bit at a sampling rate of 323MS/s while consuming a power of 2.8mW. Nonlinearity caused by internal mismatch or PVT variations can be compensated with an correction system. Compared to state-of-the-art SAR ADCs the proposed ADC matches the characteristics and advances the limitations of the conventional tracking ADC. A 94% digital implementation by standard cells and the ability to digital compensate nonlinearity demonstrate the excellent scalability with technology.