Abstract: A receiver is synchronized with a first clock frequency or signal of a transmitter for the proper reception of transmitted and received signals, such as data carrying signals (DS). The first clock frequency is for example a carrier frequency. A local oscillator generates a second clock frequency or signal in the receiver. Cycles or impulses of the second clock signal are counted between predetermined flanks of the received signal (DS) to provide a count (N). Based on the second clock signal and the count (N) a first ratio (TV) is provided that represents a first ratio between the first clock frequency or signal and the second clock frequency or signal. The first ratio is compared with a predetermined or given second ratio (TV) to provide a comparing result. The predetermined second ratio is then updated in response to the comparing result to provide an updated ratio (TV?). The present circuit is constructed to perform these steps.

Abstract: An SOI wafer including an active semiconductor material layer on an insulating layer is processed to form thereon first and second active semiconductor regions that respectively have different thicknesses and that are vertically and laterally insulated. In the process, a trench is etched into the SOI wafer, seed openings are formed in the bottom of the trench to reach the underlying active material layer, the trench is filled with epitaxially grown semiconductor material progressing from the seed openings, some of the epitaxially grown material is removed to form the second active regions, and oxide layers are provided so that the second active regions are laterally and vertically insulated from the first active regions formed by remaining portions of the active semiconductor material layer.

Abstract: A transmitted time signal carries time information encoded bit-wise by signal amplitude variations in a succession of time frames. A method involves receiving and evaluating the time signal in a receiver to acquire the time information, and then outputting from the receiver an individual data bit respectively allocated to a respective time frame during or at the end of or immediately after the respective time frame. It is not necessary to store all the data bits of a complete minute telegram in the receiver before the evaluation. The successive data bits are used by a microprocessor downstream from the receiver to produce a time signal. A circuit arrangement for a radio-controlled clock includes a receiving antenna connected to a receiver circuit that incorporates a time information decoder for decoding the time information contained in the time signal.

Abstract: A receiving unit including an operational amplifier having a fixed gain receives an electromagnetic signal, from which a voltage divider with a variable resistance generates an input voltage for the amplifier. The amplifier's output voltage is compared with a reference voltage. The variable input resistance is adjusted to vary the amplifier's input voltage, until the amplifier's output voltage lies within a defined range around the reference voltage. This adjusted resistance value is compared with nominal resistance values previously stored in a value field and respectively allocated to field strength values, to determine a field strength of the received signal. A circuit arrangement includes an operational amplifier, a memory unit connected to a processor unit, a first voltage divider, a second voltage divider, and a control element that controls the second voltage divider to provide the controlled variable input resistance.

Abstract: A transponder receives its operating energy from an external source such as a radio signal or a battery. Such transponders are used for example in a vehicle or in a remote sensor. The response range of the transponder is increased by converting the received energy into an operating voltage which in turn is used to generate a function voltage required for performing a current function sequence. The generated function voltage is checked to determine at least one characteristic of the generated function voltage. The determined function voltage characteristic, for example a voltage value directly representing the function voltage, is then used to acknowledge or reject a result of performing the function sequence. Thus, the time duration for performing any current function sequence is flexibly adapted to the current requirements of that function sequence, whereby the power consumption of the transponder is optimally reduced and the response range respectively increased.

Abstract: Transmitters respectively transmit time signals providing time information in a succession of time frames having constant duration but different encoding parameters and frequencies. A received time signal is evaluated to determine the particular transmitter that transmitted the signal. For example, the frequency, the duration and number of signal pulses representing second markers, the arrangement and sequence of signal pulses, and/or the inversion state of the signal are evaluated to identify the pertinent transmitter based on these characteristic features. The time information can be properly decoded and evaluated according to the correct protocol, which has been automatically selected.

Abstract: A time signal provides time and/or date information in a succession of time code telegrams that each include successive time frames having at least one data bit each. The time signal is received, decoded and evaluated to acquire the time information, for which only some of the data bits of a respective time code telegram are evaluated. Particularly, only those bits representing necessary time and/or date information are evaluated, while other bits containing other unneeded information are ignored or replaced by filler bits. A radio-controlled clock includes a bit decoder and an evaluating unit for decoding and evaluating only the pertinent bits, a counter that keeps track of the bit location in the telegram, and a controller that controls the decoder and/or evaluating unit to decode and evaluate only some particular ones of the received data bits in the telegram.

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 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 voltage (UE1, UE2). such as a supply voltage, is monitored and controlled to avoid damage to circuit components by maintaining a required voltage level. Dissipation power losses are reduced by switching off a monitoring circuit when monitoring is not required. For this purpose a stepped down voltage is derived from the voltage to be monitored at a tap (N1) of a voltage divider connected between ground potential and the voltage to be monitored. The derived voltage is then evaluated, for example by comparing with a reference voltage. A controllable switch is connected in series with two voltage divider elements. The switch is controlled to open for switching off the voltage divider when monitoring is not needed. The switch is closed to activate the voltage divider when monitoring is needed.

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: 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: In a method for selecting, by a base station, one or more transponders out of a plurality of transponders, selection steps are performed at least at two selection levels or stages. The base station controls all selection steps at the first and second level. The first selection level includes: each transponder generates a random transponder number, the base station generates numbered time slots, each transponder transmits a marker if and when its random transponder number coincides with a time slot number. When a single transponder random number coincides with a time slot number the respective transponder is selected by the base station. If more than one transponder random numbers coincide with a time slot number the second selection procedure is performed at a second selection level as a stochastic or a deterministic or a mixed stochastic-deterministic selection procedure.

Abstract: In a process for the transfer of data between a base station and a transponder by an electromagnetic carrier wave, on which data bits are modulated by amplitude modulation, the duration of a modulation interval of a data bit is determined and compared with a reference value, a correction value is calculated from the deviation of the actual value of the duration of the modulation interval from the reference value, and the actual values of the duration of the modulation intervals of the following data bits are corrected with the correction time. As a result of the correction, the duration of the modulation intervals may be reduced and the data transfer rate increased or the transfer rate may be adapted to the transfer conditions.

Abstract: In a new process of making a DMOS transistor, the doping of the sloping side walls can be set independently from the doping of the floor region in a trench structure. Furthermore, different dopings can be established among the side walls. This is achieved especially by a sequence of implantation doping, etching to form the trench, formation of a scattering oxide protective layer on the side walls, and two-stage perpendicular and tilted final implantation doping. For DMOS transistors, this achieves high breakthrough voltages even with low turn-on resistances, and reduces the space requirement, in particular with regard to driver structures.

Abstract: A DMOS-transistor has a trench bordered by a drift region including two doped wall regions and a doped floor region extending along the walls and the floor of the trench. The laterally extending floor region has a dopant concentration gradient in the lateral direction. For example, the floor region includes at least two differently-doped floor portions successively in the lateral direction. This dopant gradient in the floor region is formed by carrying out at least one dopant implantation from above through the trench using at least one mask to expose a first area while covering a second area of the floor region.

Abstract: To form a semiconductor component having active regions separated from one another by trenches as isolation structures, a method involves forming a shallow trench in a semiconductor body, thereafter forming a deep trench within the shallow trench in the semiconductor body, and thereafter completely driving dopant atoms into the semiconductor body to form a well region doped with the dopant. The dopant may be previously introduced by implantation into a surface layer, and then the dopant is finally completely driven into the well region by thermally supported diffusion after forming the deep trench. The shallow and deep trenches together form a compound trench with stepped side walls. Two oppositely doped wells may be formed on opposite sides of the compound trench, which thus isolates the two wells from one another. Active regions may be formed in the two wells.

Abstract: A receiving/backscattering arrangement for carrying out a contactless data transmission includes an integrated circuit having two antenna contacts, a series arrangement of three high quality capacitances connected between the two antenna contacts, whereby the middle capacitance is an MOS varactor, a controllable variable voltage source connected across the MOS varactor, and a control unit that controls the voltage source. The receiving/backscattering arrangement is especially a passive transponder with a rectifier connected between the antenna contacts, or a semi-passive transponder including a battery or solar cell, to provide the required supply voltage for the circuit. The arrangement achieves a large communication range, for receiving and modulating an interrogation signal, and backscattering the modulated response signal with a high efficiency and low losses. The integrated circuit structure is compact and economical.

Abstract: Data encoded in packets modulated onto a carrier wave is transmitted between a base station and a transponder. Each packet includes a header section that contains at least a reference symbol and that serves for adjusting one or more transmission parameters, and a further section such as a data section. The transponder transmits data back to the base station through modulation and backscattering of the carrier wave. During the transmission of the header section by the base station, the transponder transmits transponder operating information relating to the processing of data to be received and/or transmitted by the transponder, by corresponding modulation and backscattering of the carrier wave. In response to and dependent on the received transponder operating information, the base station adjusts at least one transmission parameter, whereby the highest data transmission rate within the capabilities of the particular transponder can be achieved.

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.