Time Interleaved ADCs (TIADCs) are a good solu-tion to implement high sampling rate converters at a moderate hardware cost. However, they suffer from mismatches between the ADC channels, such as offset, gain, timing skew and possibly bandwidth mismatches. These mismatches have to be corrected in order to get sufficient performances from the converter. This paper presents the classical calibration methods and focuses on the blind ones. Among those, both mixed analog-digital methods and fully digital methods are overviewed. By considering the state-of-the-art of published chips, a comparison between those methods is provided.