DC-DC converter with polarity reversal protection

A DC-DC converter, comprising:

• a first asymmetrical half-bridge circuit,
• a second asymmetrical half-bridge circuit,
• a transformer comprising first and second primary windings and first and second secondary windings, wherein the first asymmetrical half-bridge circuit is configured to generate an AC voltage at the first primary winding, and wherein the second asymmetrical half-bridge circuit is configured to generate an AC voltage at the second primary winding, and
• a rectifier circuit comprising
• an output terminal, wherein the output terminal comprises a first output terminal pole and a second output terminal pole, and
• two rectifier elements in the form of a first diode and a second diode,
• wherein the rectifier circuit is configured to rectify voltages present at the first and second secondary windings and to output a rectified voltage at the output terminal,
• wherein the rectifier circuit further comprises a polarity reversal protection transistor,
• wherein a drain-source path of the polarity reversal protection transistor is directly electrically connected to a cathode of the first diode and to a cathode of the second diode, and
• wherein the drain-source path of the polarity reversal protection transistor is looped in between the cathodes of the first and second diodes and the first output terminal pole or the second output terminal pole of the output terminal,
• wherein a first terminal of the first secondary winding is electrically connected to an anode of the first diode, and the drain-source path of the polarity reversal protection transistor and an inductor are looped in between the cathode of the first diode and the first output terminal pole of the output terminal,
• wherein a first terminal of the second secondary winding is electrically connected to an anode of the second diode,
• wherein the cathode of the first diode and the cathode of the second diode are electrically connected,
• wherein the second terminal of the first secondary winding, the second terminal of the second secondary winding and the second output terminal pole of the output terminal are electrically connected,
• wherein a constant voltage is applied to a gate terminal of the polarity reversal protection transistor, such that the polarity reversal protection transistor blocks a polarity-reversed voltage at the output terminal, and
• wherein the two rectifier elements and the polarity reversal protection transistor are integrated into a power module.