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 (T) is mapped to a difference of a length of a reference time (RT) and a length of a signal time (ST), while the reference time (RT) is generated from an instant (t 1 ) when the beginning of the time interval (T) is detected by the use the control module (CM), and the signal time (ST) is generated from an instant (t 2 ) when the end of the time interval (T) is detected by the use the control module (CM), whereas generation of the reference time (RT) and the signal time (ST) is terminated at the same instant (t 3 ).