Abstract: A method and a circuit comprising an electrically controlled transistor element (303) configured for conveying a current from an input terminal (300) to an output terminal (320), wherein the current is of a magnitude belonging within a pre-determined current range; and a control circuit configured for controlling said transistor element is such a manner that the transistor element (303) is controlled to produce a pre-selected voltage drop across the transistor element independently of the traversing current. Hereby an extremely effective circuit is provided that has high efficiency for transporting large current values form a supply module to a power consuming module and hence the option is provided of substituting the circuit according to the invention in an active system; a so-called hot swap. The circuit can also easily be dimensioned to a desired application by adding a number of transistor elements in parallel.

Abstract: A magnetic circuit with several magnetic components integrated on one or more common magnet cores is utilized in a current supply circuit known per se. The circuit comprises a transformer, the secondary winding ends of which are connected to uniform electrodes of a pair of rectifier diodes, the second electrodes of which are connected to one output terminal of the power supply circuit. Additionally, it includes two reactive components, and the first electrodes of the diodes are connected to the second output terminal of the power supply circuit via one of the reactive components. The number of turns of the two reactive components is essentially chosen to equal the number of secondary turns on the transformer. The two reactive components are positioned on each separate core part so that the resulting magnetic flux in common core parts substantially equals the difference between the magnetic flux of the two core parts, and the secondary winding of the transformer is positioned on the common core parts.

Abstract: A power supply circuit comprising a transformer and rectifier diodes, where the ends of the secondary winding are connected to uniform first electrodes of a pair of rectifier diodes (D1, D2) whose second electrodes are connected to one output terminal (-) of the power supply circuit. According to the invention, also reactive components are provided, said reactive components being connected between the other output terminal (+) of the power supply circuit and the first electrode of respective ones of the rectifier diodes. When one reactance (e.g. L2) can send current (I.sub.L2) through one (D2) rectifier diode serving as an idler diode, while the secondary winding of the transformer draws current (I.sub.L1) through the same rectifier diode, a better utilization of the transformer is obtained than in the prior art, in particular when the output voltage is relatively low, while the output current is relatively high.