A sigma delta analog to digital converter for converting an analog input into a digital output comprises a reference path for receiving a reference voltage. The reference path comprises a digital to analog converter. The digital to analog converter comprises a reference voltage input for receiving the reference voltage, wherein the reference voltage input comprises two contacts and wherein each contact is a beginning of a voltage line of two voltage lines. The digital to analog converter comprises a plurality of switches and a plurality of capacitors. The switches of the plurality of switches are configured to connect the digital to analog converter in a sampling phase with the reference voltage and to disconnect the digital to analog converter in an integrating phase from the reference voltage.