Voltage converter

A voltage converter, configured as a step-down converter, for reducing an input direct voltage into an output direct voltage that is lower than the input direct voltage, the voltage converter comprising:

• a first step-down converter circuit arrangement, comprising:
• a first semiconductor switching element having a first control input,
• a first coupled choke having a first freewheeling diode, and a first input capacitor, and
• a first output capacitor;
• and
• a second step-down converter circuit arrangement, comprising:
• a second semiconductor switching element having a second control input,
• a second coupled choke having a second freewheeling diode, and
• a second input capacitor and a second output capacitor:
• wherein the first input capacitor of the first step-down converter circuit arrangement and the second input capacitor of the second step-down converter circuit arrangement are arranged in series in order to share the input voltage;
• wherein the first semiconductor switching element and the first freewheeling diode, as well as the second semiconductor switching element and the second freewheeling diode, are arranged in series, and the first freewheeling diode and the second freewheeling diode are configured to at least one of:
• protect the respective circuit from at least one of an overvoltage of the first coupled choke and the second coupled choke, or a current flow when the respectively assigned semiconductor switching element is open, or
• enable the flow of current of the first coupled choke and the second coupled choke during a reduction of a magnetic flux of the first coupled choke and the second coupled choke;
• wherein the first coupled choke and the second coupled choke are coupled to one another in a transformer;
• wherein the first output capacitor and the second output capacitor are arranged in series and form a voltage divider;
• wherein the first step-down converter circuit arrangement and the second step-down converter circuit arrangement have a common feedback voltage divider which has a first resistor and a second resistor;
• wherein the first coupled choke and the second coupled choke have a common magnetic core, the magnetic core having at least one auxiliary winding having at least one tap for at least one of:
• at least one measurement signal, or
• the control voltage supply;
• and
• wherein the voltage converter is operated in a freely oscillating operating mode, which lies in a transition range between an intermittent operation and a continuous operation, such that there is a wait before a start of each new magnetization phase until an energy in the chokes has been completely reduced.