Abstract: An oscillator includes a resonant circuit of at least one inductance device and at least one tunable capacitance. The tunable capacitance is implemented through diffusion capacitances of at least one current-carrying transistor. The tunable capacitance has a first differential amplifier having a first transistor and a second transistor and a second differential amplifier having a third transistor and a fourth transistor Electrical properties of the first transistor and second transistor are complementary to electrical properties of the third transistor and fourth transistor, and control connections of the first transistor and the third transistor are connected to one another. Control connections of the second transistor and the fourth transistor are connected to one another. Second current connections of the first transistor and the third transistor are connected to one another, and second current connections of the second transistor and the fourth transistor are connected to one another.

Abstract: A device is disclosed for converting a complex-valued bandpass signal into a digital baseband signal.

Abstract: Vertically insulated active semiconductor regions having different thicknesses in an SOI wafer, which has an insulating layer, is produced. On the wafer, first active semiconductor regions having a first thickness are arranged in a layer of active semiconductor material. The second active semiconductor regions having a relatively smaller thickness are produced by epitaxial growth proceeding from at least one seed opening in a trench structure. The second semiconductor regions are substantially completely dielectrically insulated, laterally and vertically, from the first semiconductor regions by oxide layers. The width of the seed opening can be defined by lithography.

Abstract: A circuit arrangement for phase modulation in an input circuit of a backscattering transponder includes a varactor and at most one capacitor connected in series between two antenna terminals, as well as a varactor control arrangement applying a control voltage to the varactor to selectively vary the capacitance thereof. One of the antenna terminals is connected directly to one of the varactor terminals without a capacitor therebetween. The other antenna terminal is connected either directly or through a capacitor to the other varactor terminal. One antenna terminal and/or one varactor terminal can be grounded. A DC-decoupling capacitor can be connected between a transponder circuit unit or a circuit ground and the common junction of the antenna terminal with the varactor terminal. The circuit arrangement is simple, economical, and uses minimal chip area by omitting further capacitors between the antenna terminals.

Abstract: A circuit arrangement for phase modulation in an input circuit of a backscattering transponder includes a varactor and at least one capacitor connected in series between two antenna terminals, and at least two voltage sources selectively connected through at least two switches to at least one terminal of the varactor. A control unit selectively opens and closes the switches in response to the data to be phase-modulated onto the backscattered signal. By selectively connecting the different voltage values of the respective voltage sources to the varactor terminal(s) through the switches, the capacitance of the varactor and correspondingly the input impedance of the input circuit are thereby varied, so as to provide respective different phase positions of the phase modulation.

Abstract: A circuit having an input amplifier and a second amplifier that provides the circuit with a unity gain crossover frequency that is higher than a unity gain crossover frequency of the input amplifier is provided. The circuit has a control input coupled to a control input of the input amplifier and also has a first current connection and a second current connection. The circuit further includes an additional amplifier that is connected in series with the second amplifier and is controlled by the input amplifier.

Abstract: For transmitting data, a receiving/backscattering arrangement receives, modulates and reflects or backscatters electromagnetic waves emitted by a base station. The modulation corresponds to the data to be transmitted and is carried out selectively using first and/or second different modulation methods depending on the received field strength of the received electromagnetic waves. Preferably, phase shift keying is used especially or at least at low field strengths at far range, while amplitude shift keying is used additionally or alternatively for high field strengths at close range. The two modulation methods can be superimposed. A circuit arrangement includes two different modulator arrangements to perform the two modulation methods depending on the received field strength. The second modulator arrangement preferably comprises a multi-stage voltage multiplier circuit with a modulated switching device intervening in one of the stages to achieve the modulation.

Abstract: A semiconductor element such as a DMOS-transistor is fabricated in a semiconductor substrate. Wells of opposite conductivity are formed by implanting and then thermally diffusing respective well dopants into preferably spaced-apart areas in the substrate. At least one trench and active regions are formed in the substrate. The trench may be a shallow drift zone trench of a DMOS-transistor, and/or a deep isolation trench. The thermal diffusion of the well dopants includes at least one first diffusion step during a first high temperature drive before forming the trench, and at least one second diffusion step during a second high temperature drive after forming the trench. Dividing the thermal diffusion steps before and after the trench formation achieves an advantageous balance between reducing or avoiding lateral overlapping diffusion of neighboring wells and reducing or avoiding thermally induced defects along the trench boundaries.

Abstract: A driver circuit and a method drive an electronic component such as a laser diode with a variable electric current that is controlledly switched between at least two discrete current levels. The driver circuit includes circuit elements that damp ringing or initial transient oscillations that arise when switching the current between the current levels. The driver circuit includes a current mirror having a mirror amplification factor dependent on the frequency of the variable electric current. In order to counteract parasitic capacitances and/or inductances leading to the ringing, an inductance and/or a resistance are connected between the two series circuits making up the current mirror, a capacitance is connected parallel to a reference resistor of one of the series circuits, and/or a capacitance is connected across the voltage supply.

Abstract: The control voltage for a VCO (voltage controlled oscillator) is produced in a phase locked loop which in turn is controlled by a computer (40) including an integrated analog circuit (42). First the oscillator control voltage is set to a predetermined value. Then, voltage varying steps are performed. For performing these steps, the circuit includes a main frequency divider and a reference frequency divider both functioning as counters. The beginnings of the counting of each divider are synchronized with each other. The oscillator control voltage is increased by a predetermined voltage difference or increment when the reference divider completes its counting period prior to the main divider completing its counting. The oscillator control voltage is decreased by a predetermined voltage difference or decrement when the main divider finishes its counting period prior to the reference divider finishing its count.

Abstract: A d.c. signal controlled oscillator includes a frequency-determining network having a control input and a modulation input. A phase regulating loop includes the oscillator and components that provide a control signal to the control input. A circuit apparatus for driving the oscillator includes a modulation generator that provides a modulation signal to the modulation input, and a circuit arrangement that autonomously generates a signal depending on and representing a slope of the modulation and provides this slope signal to the modulation generator, which generates the modulation signal dependent on the slope signal.

Abstract: At least one or more terminals of an integrated circuit, such as a low- or high-side driver stage, are protected against transient or over-voltages by two pairs of diodes. A first pair of diodes includes a regular diode (D1 or D1?) and a Zener-diode (ZD1 or ZD1?). A second pair of diodes also includes a regular diode (D2 or D3) and a Zener-diode (ZD2 or ZD3). These diode pairs are looped into the respective circuit and cooperate with an n-channel MOSFET or a p-channel MOSFET to provide the required over-voltage protection, particularly for transmitter/receiver circuits and databus systems especially in motor vehicles.

Abstract: A PLL circuit arrangement includes a first frequency divider connected to a reference frequency source, a second frequency divider connected to the output of an oscillator controlled by the output of a loop filter, a phase/frequency detector that detects phase/frequency differences between the two divider outputs, a charge pump between the detector and the loop filter, a controller providing a changeable divider ratio to the first and/or second frequency divider, and a regulating signal generator that changes the output voltage of the loop filter applied to the oscillator in a controlled manner in response to a change of the divider ratio. The signal generator preferably has inputs connected to outputs of the controller and the frequency dividers, and an output connected to the charge pump and/or the loop filter to accelerate the recharging thereof in response to a change of the divider ratio.

Abstract: In a method of opening of a housing of a plastic-housed electronic module by a laser, the electronic module is protected from the effects of the laser beam and the laser beam is stopped at a suitable time by providing an end point signal detection due to the laser beam impinging on a protective layer. Thereby, after opening the housing, electrical measurements can be carried out on the electronic module.

Abstract: In a PLL circuit including a voltage-controlled oscillator, a phase detector and a final control element, the final control element contains two separate channels, between the phase detector and the voltage controlled oscillator, wherein one channel processes the useful signal components and the other channel processes the disturbance signal components of the synchronization pulses. Each channel has two tracks, for generation of a potential difference, wherein each track is connected to a capacitor plate.

Abstract: An integrated circuit preferably to be connected to a motor vehicle battery is selectively switchable between sleep and normal operating modes. The IC may include a useful control logic circuit, a wake-up circuit evaluating an input signal and responsively outputting a wake-up signal dependent on the input signal, and an input control and supply circuit connected between the wake-up circuit and the control logic circuit. The wake-up circuit includes at least one recognition circuit having an amplifier arrangement to selectively amplify the input signal, and an evaluation circuit having a switch arrangement controlled by the amplified signal and an amplifier producing the output signal. The wake-up circuit has a very low current consumption while monitoring the input signal, and produces the wake-up signal only if the input signal suitably exceeds or falls below a specified voltage threshold. The wake-up signal may activate the control circuit, which may activate the logic circuit.

Abstract: A circuit arrangement includes a first phase locked loop to generate a first oscillator frequency, a second phase locked loop to generate a second oscillator frequency, a reference frequency emitter connected to a reference frequency input of both phase locked loops, and a signal attenuator and optionally a switch connected between a master signal output of the first (master) loop and an input of the second (slave) loop. In a method, a common reference frequency is provided to both loops, the first loop generates a first oscillator frequency, and the second loop generates a second oscillator frequency that matches the first oscillator frequency in at least one operating mode and optionally differs from the first oscillator frequency in another operating mode. The frequency matching in one of the modes involves feeding an attenuated signal from the first loop operating as a master into the second loop operating as a slave.

Abstract: A circuit arrangement for detecting a received signal includes a rectifier with an input connected to a receiving antenna for rectifying an encoded received signal, a signal capacitor connected to an output of the rectifier, a discharge current sink connected to the signal capacitor, and a signal evaluating circuit connected to the signal capacitor. The discharge current sink includes a current mirror circuit of cascode-connected transistors. Thereby, the discharge current is substantially independent of the signal voltage over a larger range of voltages. This signal detection circuit is useful in transponders or remote sensors that receive and detect a signal transmitted by a base station.

Abstract: In a method of selecting one or more transponders, the time duration of a reference interval is transmitted by the base station to the transponders in the header section of an information packet, each transponder compares the respective time durations of the reference interval and of a first time interval, and the further selection of the transponder depends on the result of the comparison.

Abstract: An operating and evaluation circuit of an insect sensor is provided, which has a resistor that is dependent on insect infestation, whereby the circuit during stimulation via a transponder generates a current flow through the resistor, detects a change in the resistor as a change in voltage, and compares it with a predetermined threshold. The circuit includes a transponder-stimulated constant current source, which is connected with the resistor so that a constant voltage drops across the resistor.