Digital Blind Background Calibration of Imperfections in Time-Interleaved ADCs

Abstract

This paper presents a digital blind background calibration technique of imperfections in time-interleaved analog-to-digital converters (TI-ADCs). The proposed technique directly operates on the statistics of the input signal to continuously estimate and eliminate the conversion errors resulted from offset, gain, and timing mismatch. Behavioral simulations are presented for a 4-channel 10-bit TI-ADC in order to verify the effectiveness of the proposed method. The signal-to-noise-and-distortion ratio (SNDR) is enhanced from 33.7 dB to more than 61 dB using the introduced calibration technique. This calibration method converges after roughly $4 \times 10^{6}$ conversions.