The development of a new traceability stepup chain using digital instruments (digitisers) with direct traceability to SI would allow dynamic measurements of current and voltage waveforms. CEM has studied the feasibility of a digital counterpart for the traditional thermal-converter-based step up, which is limited to provide the RMS values of monotone signals. This paper describes and validates this new digital method, obtaining a complete set of calibrations shunt-digitizer for currents up to 1 A. The performed measurements show very promising results, comparable to the well-established thermal-converter approach results, with differences between both techniques lower than 2 μA/A up to 1 kHz.