An analog-to-digital converter (1). The analog to digital converter (1) comprises a first range-control unit (100) adapted to generate a first range-control value for controlling a size of an input range of the analog-to-digital converter (1). The analog to digital converter further comprises a second range-control unit (200) adapted to generate a second range-control value for controlling a midpoint of the input range. Further, the analog-to-digital converter (1) comprises a reference-level unit (300) operatively connected to the first range-control unit (100) and the second range-control unit (200). The reference-level unit (300) is arranged to generate a plurality of reference levels at least based on the first and the second range-control value. The analog-to-digital converter further comprises a comparison unit (400) operatively connected to the second range-control unit (200) and the reference-level unit (300). The comparison unit (400) is arranged to perform at least one comparison between a difference between an analog input value of the analog-to-digital converter (1) and the second range-control value and individual reference levels of the plurality of reference levels. The comparison unit (400) is further arranged to generate a digital output value of the analog-to-digital converter (1) based on the at least one comparison.