Abstract: An oscillator/demodulator circuit for an inductive proximity switch includes a transistor amplifier stage having an input circuit and an output circuit, a resonant circuit connected in the input circuit of the transistor amplifier stage, a device for damping the resonant circuit, a device for providing positive feedback from the output circuit to the input circuit of the transistor amplifier stage, a limiter branch connected in the input circuit of the transistor amplifier stage, a dual current mirror active in the input circuit of the transistor amplifier stage having first and second interconnected current mirrors including transistors.

Abstract: Circuit for enhancing the utilizable Hall signal of a Hall sensor, including N Hall generators being operated with impressed control current and having Hall signal paths, N voltage to current converters each having an output and each being coupled to the Hall signal path of a different one of the Hall generators, and a common output connected to each of the outputs of the voltage to current converters.

Abstract: An oscillator/demodulator circuit arrangement for an inductive proximity switch with a transistor amplifier stage having an input circuit containing an attenuatable resonance circuit and having an output circuit, with a regenerative feedback from the output circuit to the input circuit of the transistor amplifier stage, the input circuit of the transistor amplifier stage having a limiter branch therein, includes a double current mirror operatively connected in the input circuit of the transistor amplifier stage and including a first and a second current mirror coupled to one another in a manner that currents supplied thereby are subtracted from one another at a circuit output, the transistors in the second current mirror having a larger emitter surface ratio in comparison with the emitter surface ratio of the transistors in the first current mirror.

Abstract: Negative-feedback circuit for a transistor amplifier having an output stage, an output transformer being operated by the output stage and having a center tap and two ends, the center tap being connected to a supply voltage source, a first output transistor connected to one of the two ends of the transformer and a second output transistor connected to the other end of the transformer, each of the output transistors being driven by a half wave of an information signal and being load carrying during that respective half-wave only, including two circuits, one being connected to the first output transistor and the other being connected to the second output transistor for imaging the current in the output circuit of the output transistors connected thereto, and a circuit branch connected to the imaging circuits for combining the currents flowing in the imaging circuits into a full-wave voltage signal for negative-feedback.

Abstract: The invention concerns a snugly fitting denture such as bridges and the like, consisting of a metallic foundation and of a ceramic facing shell as well as a process to its manufacture. It is the object of this invention to develop a compact system for a snugly fitting denture with high firmness and mechanical loading capacity as well as with prolonged durability under the conditions prevailing in the oral cavity. This is achieved by the fact that the metallic foundation consists of a base metal alloy with a silane-content of .ltoreq.0.5% and that the ceramic facing shell is provided with a silicon-coupled adhesive plastic part. The metal base is silanized in an ultrasound bath, highly fluid prosthesis plastic is applied to its labial aspect and the facing shell is pressed-on. Thus a solid chemical bonding develops between foundation and facing shell. This compact system is without slits and does not offer any possibilities of aggression to harmful influences existing in the milieu of the oral cavity.

Abstract: Circuit for the load-proportional adjustment of the driving current of a single-ended output transistor of a transistor amplifier for a variable load of the output transistor, the output transistor having a base-emitter voltage and being operated in a common emitter circuit, having a control branch feeding the driving current to the output transistor, including a sensing transistor stage having an output circuit and being driven by the base-emitter voltage of the output transistor, a transistor serving as a driver transistor for the output transistor and being controlled by the control branch, and a coupling circuit through which current in the output circuit of the sensing transistor is feedable to the transistor serving as a driver transistor.

Abstract: Device for changing the electrical circuit configuration of integrated semiconductor circuits on chips for the adjustment and trimming of circuit parameters, including circuit connections selectively disposed in the circuit configuration of the integrated semiconductor circuits, the circuit connections being accessible from outside the circuit chips and being mechanically openable without mechanically and without electrically stressing and modifying the circuit chips.