Adaptive digital calibration of timing mismatch for TIADCs using correlation

Time-interleaved analog-to-digital converters (TIADCs) play an important role in high-speed data conversion. However, the timing mismatch in TIADCs structure will affect the performance of acquisition systems, such as the spurious free dynamic range (SFDR). In this study, we propose a new all-digital calibration technique to suppress the timing mismatches' effect by using an adaptive stochastic gradient descent technique based on the cross-correlation method and combined with the fractional delay (FD) filter. This post-processing compensation could quickly track the varying timing skew at a low complexity. The experimental results verify its effectiveness.