Abstract: An apparatus and a method for converting power from a power input to an DC output voltage or current, which apparatus has a serial resonance converter, where a first feedback circuit is connected from the output terminal to an error amplifier, where the apparatus further has a second feedback circuit with at least one first resistor that is connected to a coil and to ground, which second feed back circuit connects the line between the first resistor and the coil and towards an inverting integrator, the output of which is connected through a second capacitor to a second input at a control circuit. As a result, the oscillating frequency is under influence of a signal that depends on the voltage generated in the resistor connected in serial to the coil or transformer.

Abstract: The present invention relates to an apparatus and a method for converting power from a power input to a DC output current or voltage, where a first feedback circuit a traditional feedback. The converter type is a resonant DC-DC converter. The scope of the invention is to reach a high effective and fast responding switch mode power supply. This can be achieved with an apparatus or method comprising a second feedback circuit leading a signal from a serial resonance capacitor(s) to a reference input terminal at the control circuit, which second feedback circuit contains a signal depending on the actual change in charge of the resonant capacitor(s). This means that at high load, a very powerful signal will be transmitted through the second feedback at the control circuit that will change the operation of the circuit into a charge mode operation.

Abstract: The present invention relates to a method for protecting electronic products, which electronic product comprises an Ethernet connector, where the Ethernet connector comprises a protection circuit, which circuit comprises at least one capacitor and at least one resister, where the Ethernet connector is used to protect against high energy transients, where the Ethernet connector comprises a protection circuitry. Where the Ethernet connector comprises a protection circuitry, which protection circuitry is characterized in that in the protection circuitry is the electrically product ground and Ethernet ground connected by at least a VDR (Voltage Dependant Resistor), which VDR is connected between the Ethernet ground and the product ground in the protection circuitry.