Telefunken Electronic Gmbh

Temic Telefunken Microelectronic Gmbh

Deutsche Thomson-brandt Gmbh

Licentia Patent-verwaltungs Gmbh

Rolf Bohme

Heinz Rinderle

Gunter Gleim

Johann Traub

Martin Siegle

Jurgen Sieber

Johann Burkhart

Willy Minner

Matthias Eichin

Elke Rosch

Konrad Hirsch

A heterodyne receiver operating on the principle of synchronous modulation for time-signal reception where a first mixer is driven by the first phase-locking loop which is fed from a reference frequency source and a switchable precharging value. By means of switched frequency dividers and the precharging values, internationally different clock frequencies (JP: 40 kHz; USA/GB: 60 kHz; EU/D: 77.5 kHz) can be processed and converted to the intermediate frequencies. These are then synchronously demodulated by means of a second mixer which receives its signal from the second phase-locking loop that is driven through the intermediate frequency signal via the phase comparator, and also through the control signal of the phase-locking loop, so that only residual error adjustment need be performed.

Heterodyne receiver with synchronous demodulation for receiving time

A folding amplifier is proposed for the construction of an A/D converter to which a current signal is fed as the input signal and from which a current difference signal is derived using a reference current. This current difference signal is fed to a first current-controlled current source, which is designed as a current mirror, and also to a second current-controlled current source, whereby the first current source takes over this current when the current difference signal has a positive sign and if the current difference signal has a negative sign the second current source takes over this current. The outputs of the first and second current-controlled current sources are fed to the output of the folding amplifier. Preferably, this folding amplifier is provided with a third current-controlled current source with sign reversal whose input is connected to the outputs of the first and second current sources and whose output is a V-shaped output current signal.

Folding amplifier for the construction of an A/D converter

Conventional integrable differential amplifiers have implanted resistors as load resistors, the limited size of which represents a barrier for the minimization of current consumption. In accordance with the present invention, the load resistors are replaced by load elements that represent non-linear two-terminal elements such as diodes, the potential at these load elements is held constant via a control loop by a controlling element such as a control transistor. This allows the current consumption of differential amplifier stages to be reduced to the order of magnitude of the residual current without increasing the area required for integration of the circuit.

Electronic load resistor circuit

A filter that has a resonator operated in series resonance and a two-pole terminal resonator circuit with a resonator whose electric conductance can be divided into a useful component and a parasitic component. A first differential stage actuated by a signal source and having two active elements whose ground connections are each linked to a respective current source and to a respective connection of the two-terminal resonator. A compensation circuit having two connections and which simulates the parasitic component of the resonator electric conductance is connected to a second differential stage which actuated by the signal source, is of the same type as the first differential stage, and has two active elements whose ground connections are each linked to a respective current source and to a respective connection of the compensation circuit. An evaluation circuit is linked to the two mutually reversed, i.e. connected in phase opposition, output connections of the two differential stages.

Filter circuit with a resonator operated in series resonance

In accordance with the present invention, two unsymmetrical differential amplifier stages are fed from a common signal source that supplies an AC voltage signal, but to which the two differential amplifier stages are connected with respect to the unsymmetry in opposite senses. The outputs of the two differential amplifier stages, however, are connected with respect to the unsymmetry in like sense and to an output circuit that provides the load resistances and whose output supplies the rectified a.c. voltage signal that also has an approximately quadratic characteristic.

Circuit arrangement for rectifying an AC voltage signal with a plurality

According to the invention, a circuit arrangement includes at least two bipolar transistors, each having a base electrode, an emitter electrode and a collector electrode. The two transistors are connected together at their base electrodes and the base electrodes are connected to an auxiliary voltage. The collector electrodes are arranged to be first and second outputs of the circuit arrangement. An emitter resistor is connected to the emitter electrode of each transistor. Each emitter resistor is a pinch resistor having a gate electrode for controlling a resistance value of the respective emitter resistor. The gate electrodes of the respective pinch resistors are configured to be first and second inputs of the circuit arrangement.

Circuit arrangement with controlled pinch resistors

A receiver array in accordance with the reception principle of synchronous demodulation, in which a controllable oscillator array is pre-synchronized to a set value for the oscillator frequency by a digital first control circuit having a reference frequency source during a pre-synchronization phase, and a heterodyne signal derived from the oscillator frequency is then synchronized with phase locking to the received useful signal by switching the oscillator control input to an analog second control circuit.

Receiver having a local oscillator first synchronized to a reference

A system for regulating the transfer impedance of a plurality of current-to-voltage converters to a substantially equal value includes a reference voltage source and a reference impedance for providing a reference current. A reference current-to-voltage converter is responsive to the reference current and provides an output voltage. A comparator is responsive to the reference voltage and the output voltage and provides a control signal to the reference current-to-voltage converter and to all the other current-to-voltage converters to maintain the transfer impedance of all the current-to-voltage converters constant.

Electric circuit for stabilizing the transfer impedance of an integrated

In an input circuit for high-frequency amplifiers having four transistors of the same conductivity type, the emitters of the first and second transistors (T1, T2) are connected to a reference point (M). The base of the first transistor (T1) forms the input (A) of the circuit and the base of the second transistor (T2) is connected to the collector of the first transistor (T1). The collector of the first transistor (T1) is connected to the emitter of the third transistor (T3) and the collector of the second transistor (T2) to the emitter of the fourth transistor (T4). The bases of the third and fourth transistors (T3, T4) are connected to one another, and at least one of the collectors of the third or fourth transistors (T3, T4) is connected to a current supply (I3, I4).

Input circuit for high-frequency amplifiers

In a band-pass amplifier having differential stage comprising two transistors fed from a joint current source, the collector of the first transistor is connected via a resistor to the base of a third transistor complementary to the first and second transistor, and the collector of the second transistor is connected via a resistor to the base of a fourth transistor complementary to the first and second transistor. The emitters of the third transistor and fourth transistor are connected to a supply voltage source, and the collectors of the third and of the fourth transistor form the output terminals of the amplifier.

Band-pass amplifier

A controllable integrator for a bipolar integrated filter includes a voltage-current-transformer, a current distribution multiplier and an integrating amplifier. The voltage-current-transformer includes two transistors having their emitters connected via a converting resistor and two current sources each connected to a respective one of the emitters of the two transistors. The current distribution amplifier includes two logarithmic diodes each connected to a respective one of the collectors of the two transistors, a differential stage having differential inputs connected to the two logarithmic diodes, a controllable current source for supplying current to the differential stage, and a current mirror having an output and comprising two transistors of one conductivity type having emitters connected to a source of supply voltage and collectors connected to the output of the differential stage. The integrating amplifier includes an inverting amplifier having an input circuit including an input transistor of the one conductivity type, the input transistor having a base connected to the output of the current mirror and an emitter connected to the same source of supply voltage.

Controllable integrator

At a reference current source with two transistors and a controlled double current source, the base of the second transistor is connected to the collector of the first transistor, the emitter of the first transistor is connected to a reference point, the first terminal of the controlled double current source is connected to the first transistor, and the second terminal of the controlled double current source is connected to the collector of the second transistor. Either a first resistor is inserted between the base and the collector of the first transistor, and the emitter of the second transistor is connected to the reference point or the first resistor is inserted between the emitter of the second transistor and the reference point, and the base and the collector of the first transistor are connected to one another. A resistor is connected between the base of the first transistor and the reference point and/or a resistor is connected between the collector of the second transistor and the reference point.

Reference current source

The present invention relates to a band gap circuit for providing an integral multiplication of an elementary band gap voltage. The circuit comprises a first transistor having its base connected to its collector via a resistor, a second transistor which is connected at its base to the collector of the first transistor, and a third transistor which is connected at its base to the collector of the second transistor, with the emitters of the three transistors being connected to one pole of a supply source. A fourth transistor is provided in emitter follower configuration and connected between the emitter of the fourth transistor and a connection point, is a series connection comprising at least one resistor and at least one diode.

Band gap circuit

A thermoelectric level measuring device for measuring the fill level of a container having a filling material therein and a free space above the filling material comprises a series connection of three sensing resistors, the first of which is always surrounded by the filling material, the second of which is intended to be surrounded by the filling material and by the free space and the third of which is always located in the free space and an evaluation circuit connected to each end of the series connection and to the connection points between the sensing resistors.

Growing community of inventors

Bad Friedrichshall, Germany

Rolf Bohme