A method for indirect conversion of a voltage value to a digital word consisting in sampling an input voltage through a parallel connection of a sampling capacitor to a source of the input voltage, and next in mapping a sample value of the input voltage to a time interval, and in assignment of a corresponding value of n-bit output digital word by the use a control module characterized in that the time interval is mapped to a difference of a length of a reference time and a length of a signal time, while the reference time is generated from an instant when the beginning of the time interval is detected by the use the control module, and the signal time is generated from an instant when the end of the time interval is detected by the use the control module, whereas generation of the reference time and the signal time is terminated at the same instant.