High speed Continuous Time Delta Sigma Modulators (CTDSM) use time-interleaving to alleviate the regeneration time constraints on the quantizer. However, gain mismatch across the time interleaved channels causes folding of out-of-band quantization noise into the signal band thereby degrading the achievable Signal-to-Noise-Distortion-Ratio (SNDR). This work studies several mixed signal calibration techniques to addressthe gain mismatch problem and compares their performances. A variant of the sign-sign LMS technique is proven to be an efficient solution in terms of area, power and convergence time.