Background Calibration of Multiple Channel Mismatches in Time-Interleaved ADCs

Time-Interleaved Analog-to-Digital Converter (TIADC) is a promising approach to meet the requirement of high speed wireless communication systems. However, mismatches between the channels of TIADCs generate unwanted distortions at the output spectrum. This paper demonstrates a fully digital background calibration technique to identify and compensate three all deviations which are offset, gain and timing mismatches for TIADCs. In which, offset mismatch is corrected by computing the average of the output samples of each channel. The gain and timing mismatches are compensated by using LMS algorithm and the modulation matrix m[n]. The simulation results show that the performance of the ADC is improved by 41.32 dB for SNDR and 64.6 dB for SFDR.