A Low-Complexity Timing Mismatch Calibration Method for Four-Channel Time-Interleaved ADCs Based on Cross Correlation

摘要

This paper proposes an all-digital blind calibration architecture for timing mismatch of a four-channel time-interleaved analog-to-digital converter (TIADC). By calculating the cross-correlation between the signal and its derivative, the linear combination of the timing mismatch can be estimated. Then the mismatch-induced error signal is calibrated by the cascade of the differentiator and multiplier. Simulation results of a 12-bit 1GS/s four-channel TIADC behavioral model verify the effectiveness of our method. The Spurious Free Dynamic Range (SFDR) is enhanced from 34.49dB to 76.21dB. Compared with other methods, this method requires only one filter, which has the advantages of low hardware cost for implementation.