Abstract: Methods and arrangements are provided for regulating low output voltages in multiple output flyback DC/DC converters that generate, in addition to a main output DC voltage, at least one additional output DC voltage. Converter arrangements include a transformer with a primary winding connected in series with a primary switch, a first secondary winding connected in series with a first rectifier to a first output capacitor for generating the main output DC voltage, and a secondary winding connected in series with a synchronous rectifier to a second output capacitor for generating the additional output DC voltage.

Abstract: A MOSFET is used as a synchronous rectifier in a fly-back DC/DC converter and connected in series with a secondary winding of a transformer. The MOSFET is repetitively turned on and off in response to the turning off and on of a primary switch connected in series with a primary winding of the transformer. Circuit elements on the secondary winding side detect voltage transients across the MOSFET caused by reverse currents when it is turned off and shorten at least a next on-period of the MOSFET in response to the detection of such transients.

Abstract: To generate, in addition to a main output DC voltage (U1), at least one additional output DC voltage (U2) in a flyback DC/DC converter having a transformer (TR) with a primary winding connected in series with a primary switch (T1), a first secondary winding (N1+N2) connected in series with a first rectifier (D1) to an first output capacitor (C1) for generating said main output DC voltage (U1), and a second secondary winding (N2) connected in series with a a synchronous rectifier (T2) to a second output capacitor (C2) for generating said additional output DC voltage (U2), an error amplifier (3) is provided to compare the actual value of said additional output DC voltage (U2) with a desired value, and a control circuit (C4, R4, R3, T5) is interconnected between the error amplifier (3) and the synchronous rectifier (T2) to adjust the turn-off time of the synchronous rectifier (T2) in response to the ratio between the actual value of said additional output DC voltage (U2) and the desired value to adjust the

Abstract: To control a MOSFET (T2) used as a synchronous rectifier in a fly-back DC/DC converter and connected in series with a secondary winding of a transformer (TR), the MOSFET (T2) being repetitively turned on and off in response to the turning off and on of a primary switch (T1) connected in series with a primary winding of the transformer (TR), means (C3, T5) are provided for detecting voltage transients across the MOSFET (T2) caused by reverse currents upon its turn-off, and for causing it to shorten at least its next on-period in response to the detection of such transients.

Abstract: In an arrangement for supplying energy from an a.c. voltage source that includes a rectifier bridge (D1) and a converter (TR1, D5, C4), an inductor means (L1) is connected between a first output terminal on the rectifier bridge and a valley-fill circuit (10) that includes at least two capacitors (C1, C2). The converter includes a transformer (TR1) having a primary winding which together with a controllable switch means (SW1) is included in a loop that extends from a second output terminal on the rectifier bridge to the interconnection junction between the inductor means and the valley-fill circuit (10). When the absolute value of the source voltage is greater than or approximately equal to a highest intermediate voltage including the voltage across at least one capacitor in the valley-fill circuit, energy is supplied from the source to the inductor means and to the valley-fill circuit.

Abstract: A voltage doubler rectifier circuit which can be switched to different mains voltages. The circuit includes two pairs of series-coupled diodes and respectfully arranged to form a full-wave rectifier. A first terminal of a coil is connected to the positive side of the full-wave rectifier, and a second terminal of the coil is connected to an anode of a fifth diode. The anode of a sixth diode is connected to a cathode of the fifth diode via two series-coupled capacitors, and a cathode of the sixth diode is connected to a further coil. A first terminal of a switching means is connected between the anode of the fifth diode and the second of the coil. A second terminal of the switching means is connected to a coil which is connected to the negative side of the full-wave rectifier. A switch is connected between the connecting line of the diodes in one of the diode-pairs in the full-wave rectifier and the line connecting the capacitors.

Abstract: The present invention relates to a snubber circuit, a voltage converter circuit as well as a method where the voltage converter circuit comprises a coupling element (DF), which can be influenced to conduct and not to conduct and across which the snubber circuit is connected, which comprises a first series circuit comprising a first capacitor (C1) and a first diode (D1) in parallel with at least one second series circuit comprising a second capacitor (C2) and at least one second diode (D2). All capacitors in the snubber circuit form a capacitive series circuit in parallel with the coupling element (DF), which has its beginning in the first capacitor (C1).