Abstract: An inductive electric energy transmission circuit includes: an oscillating circuit; a push-pull circuit including a first switching transistor and a second switching transistor that are configured to alternate a current flow through the oscillating circuit. The circuit arrangement also includes, a control circuit including first and second control transistors configured to control the first and second switching transistors; and a frequency generator configured to generate an output signal, wherein the output signal is adapted to drive the control transistors.

Abstract: An inductive electric energy transmission circuit includes: an oscillating circuit; a push-pull circuit including a first switching transistor and a second switching transistor that are configured to alternate a current flow through the oscillating circuit. The circuit arrangement also includes, a control circuit including first and second control transistors configured to control the first and second switching transistors; and a frequency generator configured to generate an output signal, wherein the output signal is adapted to drive the control transistors.

Abstract: The invention relates to a method and a circuit for measuring a voltage and a temperature and for generating a voltage with adjustable temperature dependence.

Abstract: The invention is directed to a switched mode power supply, in particular a flyback converter, with a device for limiting the output voltage. To provide a safeguard against excessive output voltages, a Schottky diode is connected in reverse direction between the output terminals of a switched mode power supply of the invention.

Abstract: The invention is directed to a switched mode power supply, in particular a flyback converter, with a device for limiting the output voltage. To provide a safeguard against excessive output voltages, a Schottky diode is connected in reverse direction between the output terminals of a switched mode power supply of the invention.

Abstract: The invention is directed to a method and a circuit arrangement for determining the quantity of the material cut by an electrically powered cutting tool. According to the present invention, the fluctuations of the current consumed by a drive motor are detected, filtered and evaluated. By a comparison with a reference value, it is possible to determine the soiling of the cutting tool with cut residues. The invention is particularly suitable for use in shaving apparatus.

Abstract: The invention is directed to an electronic switched-mode power supply for supplying power to an electrical energy-absorbing device from an AC or DC voltage source of different voltage levels, with a primary switched-mode flyback converter which includes a transformer having its secondary winding connected in series with the electrical energy-absorbing device and a first diode, while its primary winding is connected in series with the collector-emitter circuit of a first transistor having its base connected to the one end of the secondary winding of the transformer through a feedback capacitor, the base of the first transistor being further connected to the one pole of the input voltage source, wherein several feedback capacitors are provided which, during the transformer discharge cycle, are connected to the secondary winding of the transformer, acting as parallel-connected capacitors, and which, during the transformer charge cycle, are connected to a branch comprising the base-emitter circuit of the first tr

Abstract: A method of determining and displaying the charge status of a storage battery of a battery-operated appliance, such as a razor. A time-based charge status is calculated, based at least in part on the cumulative operating time of the appliance since recharging. The battery terminal voltage is also monitored. The time-based charge status is displayed until the battery voltage indicates a low voltage condition, at which point a low-charge alert indicator is displayed only if the time-based charge status is below a predetermined level (i.e., if the cumulative operating time is above a predetermined level). Methods of detecting battery aging, and for accounting for periods of excessive current flow, are included.

Abstract: The invention is directed to a switched-mode power supply with a primary switched-mode flyback converter for the controlled supply of an electrical load from an input voltage source of optionally different voltage types and voltage levels, in which a series arrangement comprising of the primary winding of a transformer, the main current path of a a first controllable semiconductor switching device, and a first resistor is connected in parallel with the input voltage source. The secondary winding of the transformer is connected in series with a diode and the load. The base of the first controllable semiconductor switching device is connected to an arrangement that limits the maximum peak current of the first controllable semiconductor switching device in dependence upon the output current and that detects the voltage drop caused by the output current through the secondary winding along the internal impedance of the secondary winding of the transformer.

Abstract: An electronic switched-mode power supply for supplying current to an accumulator and to an electrical load adapted to be switched on, includes a self-oscillating flyback converter having a transformer, a switching transistor with an emitter resistor, a feedback circuit, and a control circuit influenced by the accumulator voltage. The power supply further includes an interrupting device which turns the switching transistor off for a prolonged period when, with the switched-mode power supply in the pulsating mode, the ratio of oscillation off-time to the duration of oscillation bursts exceeds a predetermined magnitude.

Abstract: In an electronic power supply unit to power an accumulator with a blocking oscillator-type converter synchronized on the primary side, the primary winding of the transformer is connected in series with the collector-emitter path of a first transistor, the base of which is controlled by a second transistor. A flip-flop consisting of a third and fourth transistor blocks the first transistor when a predetermined upper switch-off voltage is reached at the accumulator and releases it when the switch-on voltage falls below a predetermined lower level.

Abstract: The variation of the time (t2) in which current flows from the chock (n1) of the switching power supply to the load (C3, RL), which variation is necessary for the regulation of the output voltage (Ua), is accomplished by means of a threshold switch (S) short-circuiting the coil of the choke.

Abstract: An electronic switching power supply for supplying power to an electrical load from a variable voltage level AC or DC voltage source having first and second terminals, the power supply including a transformer having a primary coil and a secondary coil, a first terminal of the secondary coil being connected to the electrical load, a first transistor connected in series with the primary coil, a first diode connected in series with the secondary coil and the electrical load, a first capacitor connected between the base of the first transistor and a second terminal of the secondary coil, a second transistor, the collector-emitter line of which is connected across the voltage source, a first resistor connected between the first terminal of the secondary coil and the collector of the second transistor, a second resistor connected between the first terminal of the secondary coil and the emitter of the first transistor, and a discharge circuit connected between the first capacitor and the electrical load, whereby the

Abstract: A supply circuit for supplying an electrical load with a relatively constant current from a variable voltage input source, the supply circuit including a blocking oscillator including a transformer with primary and secondary windings and a switching transistor, the load terminals of the switching transistor being connected in series with the primary winding across the voltage input source, a resistor-capacitor circuit connected between the secondary winding and a control terminal of the switching transistor, a diode connected between the secondary winding and a first terminal of the electrical load, a voltage feedback connection for applying to a first load terminal of the switching transistor a portion of the secondary winding voltage, and a reference voltage source connected to the control terminal of the switching transistor.