In the work, a description is given of a method for temporarily compressing signals when several ADCs are connected in parallel. The digital channel calibration method is based on an advanced least-squares method. An algorithm based on the recursive least squares method is used to adjust the offset of the reference voltage and gain. An advantage of the proposed method on the basis of an iterative algorithm is high speed and high accuracy of tuning the ADC channels in comparison with the method based on the least squares method. To implement the «averaging» procedure, a numerical method for Euler integration is proposed. The proposed calibration method is frequency independent and has the same efficiency in the entire input signal band. The results of simulation modeling are presented, including a spectral analysis of the output signal before and after calibration.