One method for achieving high-speed waveform digitizing uses time-interleaved A-D Converters (ADCs). It is known that, in this method, using multiple ADCs 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 for automatic test equipment applications. This method can be applied to any number of interleaved ADCs, and it does not require any additional hardware; good correction and improved accuracy can be obtained simply by adding a little to the computing overhead.

This letter presents an analysis of characteristics of multiphase buck converters with coupled inductors. We derive equivalent inductances that provide both low per-phase steady-state ripple current and fast transient response. The characteristics of coupled-inductor circuits--low per-phase ripple current and fast response--were examined and verified by circuit simulation and experiments.