Interleaving is one method of configuring a high-speed waveform digitizer. It is known that, in this method, using multiple A-D converters (ADC) enables sampling at a rate higher than the sampling rate of the ADC being used. Degradation of the dynamic range, however, results from such factors as phase error in the sampling clock applied to the ADC, and mismatched frequency characteristics among the individual ADCs. This paper describes a method for correcting these mismatches using a digital signal processing (DSP) technique. This method does not require any additional hardware; good correction and improved accuracy can be obtained simply by adding a little to the computing overhead