Abstract: An etching gas mixture containing CHF3, SF6 and a non-oxidizing gas such as Ar is used as an etching gas mixture for the anisotropic plasma-chemical dry-etching of a silicon nitride layer differentially or selectively relative to a silicon oxide layer. The gas mixture does not contain oxygen, chlorine, bromine, iodine or halides in addition to the above mentioned constituents, so that the process can be carried out in reactor systems equipped with oxidizable electrodes. By adjusting the gas flow rates or composition ratios of CHF3, SF6, and argon in the etching gas mixture, it is possible to adjust the resulting etching selectivity of silicon nitride relative to silicon oxide, and the particular edge slope angle of the etched edge of the remaining silicon nitride layer. A high etch rate for the silicon nitride is simultaneously achieved.

Abstract: A method of and device for recognizing a network-synchronous interfering signal during a data transmission in which pauses occur between useful signals, with the duration of a shortest pause being Tp and a main frequency being f are disclosed. The method includes the steps of defining a time span Td being shorter than the shortest pause Tp, but longer than the longest period 1/f or ½ f, of a network-synchronous interfering station; determining whether pauses occur that are longer than Td during a time period T check>Td; and interpreting an occurrence of pauses as the presence of a useful signal without a network-synchronous interfering signal, and interpreting a lack of an occurrence of pauses as the presence of an interfering signal.

Abstract: The method of cryptological authentification in a scanning identification system comprising a base station, which supplies energy via the alternating field to a transponder connected to the object to be identified, includes the following method steps. For essentially the entire communication between the base station and the transponder, the base station generates an inquiry signal. Upon receiving the inquiry signal transmitted by the base station, the transponder responds with an identification number stored in its memory. The base station then encodes a first bit sequence it has generated by using a key bit sequence that is allocated to the identification number of the transponder, and transmits the second bit sequence obtained in this manner to the transponder. When the second bit sequence is received, the transponder generates a checking bit sequence from the second bit sequence, and, following the complete reception of the second bit sequence, transmits this checking bit sequence to the base station.

Abstract: A modulation method for transponders where data transmission from the transponder to the read-write device is ensured even if the transponder circuits are supplied only with the minimum requisite operating voltage in that the amplitude of modulation voltage provided by a modulator is caused by reducing the supply current flowing in the transponder.

Abstract: A method for setting the trigger power of transmitter diodes that transmit data via optical paths allows the transmission power to be adjusted and adapted to the communication distance. The trigger power is determined for the present communication distance on the basis of a test signal before data transmission begins. A circuit arrangement implementing the method includes a driver circuit with a switching device that switches a circuit junction point selectively to a supply voltage or to a constant reference voltage, a voltage-controlled resistor which delivers the driver current and is controlled from the circuit junction point, and a voltage-controlled measuring resistor which delivers a measured current with a fixed relationship to the driver current and is controlled from the circuit junction point. Since the set trigger power can be reduced, the power consumption for data transmission can be reduced considerably.

Abstract: A signal when transmitting digital transmission signals between a transmitter unit and at least one receiver unit, one signal lead is generally required as a transmission medium for each digital transmission signal. To permit simultaneous transmission of several digital transmission signals through a common signal lead, the digital transmission signals (S11 . . . S10) are totaled with several logical signal levels in the transmitter unit (1) to form a multilevel signal (m). This multilevel signal (m) is transmitted from the transmitter unit (1) to the receiver unit (3) through a signal lead (2). For the purpose of forming digital received signals (S31 . . . S3n) corresponding to the digital transmission signals (S11 . . . S10), the received multilevel signal (m) is compared in the receiver unit (3) with signal thresholds (V1 . . . Vn) located between the logical signal levels of the multilevel signal (m).

Abstract: The invention relates to a method for calibrating an oscillating receiver circuit of a transponder in an RFID system to resonance to the frequency of an inquiry signal transmitted by a reader, the oscillating receiver circuit comprising at least one inductive resistor and at least one capacitor. Immediately after the start of reception of the inquiry signal, capacitors are connected in increments to the capacitance of the oscillating receiver circuit until such time as the rectified, smoothed inquiry signal assumes a maximum voltage value. This active self-calibration is performed upon each initialization of the transponder but can also be addressed by having the reader send a special sequence to the transponder.

Abstract: A blinker-hazard flasher circuit has a single comparator (37) for comparing measured circuit output signals (36) containing information with reference signals having different voltage threshold levels to ascertain the information regarding the status of the flasher circuit, for example whether there is a short-circuit or whether the lamps operated by the circuit are in an operational or failed condition. A reference signal generator (40) for generating reference signals at the different voltage threshold levels receives control signals from a central processing unit. These control signals determine the sequence of the voltage threshold levels. The different levels of the reference signals provide different comparator output signals which are further processed and evaluated for obtaining the status information in response to the measured circuit output signals.

Abstract: In a method for calibrating or aligning a multistage selective amplifier including an oscillator circuit and at least one tuning circuit, the tuning voltages respectively necessary for aligning the respective tuning circuits to the required receiving frequency are calculated directly from a mathematical relationship between the respective tuning voltage and the oscillator voltage. In order to achieve this, a characteristic multiplicative coefficient and a characteristic additive factor for each tuning circuit are stored in a memory upon manufacturing or switching on the device. In order to select a desired receiving frequency, the respective stored values as well as an oscillator voltage are provided to an amplification circuit, which correspondingly amplifies the oscillator voltage by the multiplicative coefficient and the additive factor and then provides the resulting output value as a tuning voltage to the respective tuning circuit.

Abstract: Method for automatically controlling a controlled variable. In a feedback control process, a control loop is used to compare the controlled variable with a command variable that determines the setpoint of the controlled variable and minimizes a deviation between setpoint and actual value of the controlled variable with the help of a manipulated variable that acts on the controlled variable. A disadvantage of this process is the transient behavior of the control loop due to temperature influences and degradation phenomena. The method according to the invention is intended to prevent a change in the transient behavior of the control loop. In accordance with the invention, the loop gain (A) of the control loop (1) is regulated to a value at which the actual value of the controlled variable (x) overshoots the setpoint value (s) by a predetermined tolerance value (m) as the result of a pulse-shaped change in the command variable (w).

Abstract: In a known bitable flip-flop, a first inverter stage (1) is driven by an input signal (D), a second inverter stage (2) by a clock signal (CLK), and a third inverter stage (3) by an output signal (INV2) of the second inverter stage (2). In order to buffer the output signal levels of the inverter stages, the first and third inverter stages (1, 3) can be switched into a disabling state by the clock signal (CLK) and the second inverter stage (2) by an output signal (INV1) of the first inverter stage (1). The new bistable flip-flop is to be set independently of the input signal. For setting the flip-flop, preferably of CMOS design, field-effect transistors (M10, M11) are provided in the third and second inverter stages (3, 2) which inhibit disabling of the third inverter stage (3) by a set signal (SET) and a signal (SETN) that is complementary to it and which allow disabling of the second inverter stage (2) independently of the output signal (INV1) of the first inverter stage (1).

Abstract: An electronic blinker circuit for a vehicle has an analog relay control section (24) and a digital circuit control section (25) arranged in a housing having only eight terminals. A holding circuit in the digital circuit section prevents an unintended oscillation when relay contacts are opened while a manual warn-blinker switch is still closed. When the engine ignition is switched off the blinker circuit requires a low quiescent current flow that is typically only 10 .mu.A.