A low complexity all-digital background calibration technique based on statistics is proposed. The basic idea of the statistics\ncalibration technique is that the output average energy of each channel of TIADC will be consistent ideally, since each channel\nsamples the same input signal, and therefore the energy deviation directly reflects the mismatch errors of channels. In this work,\nthe offset mismatch and gain mismatch are calibrated by an adaptive statistics calibration algorithm based on LMS iteration; the\ntiming mis match is estimated by performing the correlation calculation of the outputs of subchannels and corrected by an improved\nfractional delay filter based on Farrow structure. Applied to a four-channel 12-bit 400MHz TIADC, simulation results show that,\nwith calibration, the SNDR raises from 22.5 dB to 71.8 dB and ENOB rises from 3.4 bits to 11.6 bits for a 164.6MHz sinusoidal input.\nCompared with traditional methods, the proposed schemes are more feasible to implement and consume less hardware resources.
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