Abstract: A method for preparing a current measuring arrangement of a switched mode power supply comprising a switched mode converter, and a controller for controlling the switched mode converter to convert an input voltage to an output voltage by means of controlling the duty cycle, is provided. A model, in which the output current of the converter is determined from variables and one or more model parameters, wherein the variables comprise the input voltage, the output voltage, and the duty cycle, is formed. The variables are varied while the output current is measured. The one or more model parameters is/are estimated from the varied variables and the measured output current by means of regression analysis and the model and the one or more estimated model parameters to be used by the current measuring arrangement during use of the switched mode power supply are stored.