Current-controlled active diode

An active diode circuit for letting current pass in one direction and substantially blocking current in the opposite direction, the active diode circuit comprising:

• a transistor;
• a control voltage generation circuit for generating a control voltage that is supplied to a control terminal of the transistor;
• a voltage sensing circuit for detecting a voltage drop across the transistor;
• and
• an oscillation sensing circuit for detecting an oscillation of the detected voltage drop,
• wherein the control voltage generation circuit is configured to generate the control voltage in dependence on the detected voltage drop and a detection result of the oscillation sensing circuit.

A method of controlling a transistor to function as an active diode so that current may pass in one direction and is substantially blocked in the opposite direction, the method comprising:

• detecting a voltage drop across the transistor;
• detecting a quantity indicative of a current flowing through the transistor;
• and
• generating a control voltage that is supplied to a control terminal of the transistor in dependence on the voltage drop and the detected quantity,
• wherein the control voltage is generated in such a manner that the current may pass through the transistor if the voltage drop satisfies a first condition, and the transistor is driven in a fully conducting state if the detected quantity satisfies a second condition;
• and
• wherein generating the control voltage involves:
• comparing the detected quantity to a predetermined threshold, and
• if the detected quantity exceeds the predetermined threshold, outputting, as the control voltage, a first voltage that is sufficient to drive the transistor in the fully conducting state.

A method of controlling a transistor to function as an active diode so that current may pass in one direction and is substantially blocked in the opposite direction, the method comprising:

• detecting a voltage drop across the transistor;
• determining whether an oscillation of the detected voltage drop is present;
• and
• generating a control voltage that is supplied to a control terminal of the transistor in dependence on the voltage drop and a result of said determination,
• wherein the control voltage is generated in such a manner that the current may pass through the transistor if the voltage drop satisfies a first condition, and the transistor is driven in the fully conducting state if it is determined that oscillation of the voltage drop is present.