The traditional TIADC timing mismatch chopping modulation calibration cannot be extended to multi-channel. The improved timing mismatch chopping modulation calibration algorithm adds the single channel and the adjacent channel output to detect the timing mismatch. It can be applied to the detection of arbitrary channel timing mismatch. Compensation is implemented by first-order Taylor approximation, which avoids the complex filter design in traditional algorithms. However, when the input signal frequency exceeds the Nyquist frequency of sub-channel, the calibration direction of the calibration algorithm will be wrong, resulting in the failure of calibration system. Therefore, this paper proposed a new calibration direction correction algorithm that can meet the effective calibration of the Nyquist frequency range of the whole system. Simulation results show that when applied to a 4-channel, 1 GS / s, 12-bit TIADC and when the input signal frequency is 450 MHz, the signal-to-noise distortion ratio ( SNDR) of the system is increased from 28. 4 to 73. 1 dB, and the spurious-free dynamic range (SFDR) is increased from 30. 7 to 88. 9 dB.