A Direct Current, DC, voltage source arranged for providing a DC voltage based on an input voltage between a first input terminal and a second input terminal, wherein a resistor (Rset) is connectable between the first input terminal and the second input terminal, wherein said DC voltage source comprises: - a transformer arranged for receiving a supply current, at a first side of the transformer (L1a), and for transforming said supply current to a circulating current at a second side of the transformer (L1b); - said first and said second input terminal for receiving said input voltage for setting a DC voltage to be provided by said DC voltage source; - a first diode, wherein an anode of said first diode is connected to a first end of said second side (L1b) of said transformer, and wherein a cathode of said first diode is connected to said first input terminal; - a branch diode, wherein an anode of said branch diode is connected to the first end of said second side (L1b) of said transformer; - a current regulator circuit having an input node, a cathode side and an anode side, wherein: - said input node is connected to said second input terminal, - said cathode side is coupled to said first end of said second side of said transformer via said branch diode and shunts said first diode as well as said first and second input terminal; - said anode side is connected to a second end of said second side (L1b) of said transformer, wherein the DC voltage source further comprises a current setting resistor coupled between said input node and said anode side, wherein the current setting resistor is for setting a predetermined amount of current, wherein said current regulator circuit is arranged for assuring that the predetermined amount of current is withdrawn from said circulating current, wherein said predetermined amount of current flows via said first diode, said first and second terminal and said current setting resistor back to said second end of said second side of said transformer, and for assuring that a remaining current of said circulating current flows via said branch diode, via said cathode side, via said anode side, back to said second end of said second side of said transformer thereby not flowing via said first diode. - a transformer arranged for receiving a supply current, at a first side of the transformer (L1a), and for transforming said supply current to a circulating current at a second side of the transformer (L1b); - said first and said second input terminal for receiving said input voltage for setting a DC voltage to be provided by said DC voltage source; - a first diode, wherein an anode of said first diode is connected to a first end of said second side (L1b) of said transformer, and wherein a cathode of said first diode is connected to said first input terminal; - a branch diode, wherein an anode of said branch diode is connected to the first end of said second side (L1b) of said transformer; - a current regulator circuit having an input node, a cathode side and an anode side, wherein: - said input node is connected to said second input terminal, - said cathode side is coupled to said first end of said second side of said transformer via said branch diode and shunts said first diode as well as said first and second input terminal; - said anode side is connected to a second end of said second side (L1b) of said transformer, wherein the DC voltage source further comprises a current setting resistor coupled between said input node and said anode side, wherein the current setting resistor is for setting a predetermined amount of current, wherein said current regulator circuit is arranged for assuring that the predetermined amount of current is withdrawn from said circulating current, wherein said predetermined amount of current flows via said first diode, said first and second terminal and said current setting resistor back to said second end of said second side of said transformer, and for assuring that a remaining current of said circulating current flows via said branch diode, via said cathode side, via said anode side, back to said second end of said second side of said transformer thereby not flowing via said first diode. - said input node is connected to said second input terminal, - said cathode side is coupled to said first end of said second side of said transformer via said branch diode and shunts said first diode as well as said first and second input terminal; - said anode side is connected to a second end of said second side (L1b) of said transformer, wherein the DC voltage source further comprises a current setting resistor coupled between said input node and said anode side, wherein the current setting resistor is for setting a predetermined amount of current, wherein said current regulator circuit is arranged for assuring that the predetermined amount of current is withdrawn from said circulating current, wherein said predetermined amount of current flows via said first diode, said first and second terminal and said current setting resistor back to said second end of said second side of said transformer, and for assuring that a remaining current of said circulating current flows via said branch diode, via said cathode side, via said anode side, back to said second end of said second side of said transformer thereby not flowing via said first diode.