An apparatus for calibrating a time-interleaved analog-to-digital converter including a plurality of time-interleaved analog-to-digital converter circuits is provided. The apparatus includes an analog signal generation circuit configured to generate an analog calibration signal based on a digital calibration signal representing one or more digital data sequences for calibration. The analog calibration signal is a wideband signal. Further, the apparatus includes a coupling circuit configured to controllably couple an input node of the time-interleaved analog-to-digital converter to either the analog signal generation circuit or to a node capable of providing an analog signal for digitization.