Abstract: A circuit for triggering warning lamps including a self-conductive transistor circuit with a triggering circuit connected to the supply voltages. The triggering circuit keeps the transistor circuit blocked if the supply voltages are proper. If voltage fails, the transistors of the self-conductive transistor circuit open a current path from the warning lamp terminal to the control terminal of the power driver which results in switching on of the power driver and, thus, of the warning lamp.

Abstract: A circuit configuration for the control of a servomotor (M) with the aid of current pulses supplied by a current-controlled final stage (1) of a control system. The pattern of current rise is analyzed after actuation of the final stage (1) for identifying a short circuit in the servomotor (M) across the power supply system (+U.sub.B). An excessively high current (I.sub.K), after a measuring period (T.sub.M), commencing after the transistor (LT) of the final stage (1) has been placed in saturated state, is indicative of a short circuit.

Abstract: A circuit configuration which serves to condition the output signal of a rotational speed sensor, e.g., the wheel sensor of an automotive vehicle. The circuit configuration includes a trigger circuit, the "hysteresis" or trigger thresholds thereof being controllable, and includes circuits for determining a coupling factor which, multiplied by the frequency of the sensor signal corresponding to the speed of rotation, forms the amplitude of the sensor output signal. To determine the coupling factor, and to adjust the hysteresis, threshold values are predefined for the output signal of the rotational speed sensor. Upon start of the vehicle, the coupling factor is determined from the frequency of the sensor signal at the point of time the threshold values are reached, and the hysteresis is adjusted accordingly.

Abstract: A circuit configuration for an electronic controller has a monitoring circuit which, upon detecting a defective condition, malfunction or defective power supply, maintains the actuator elements of the controller in their initial positions or restores the actuator elements of the controller to their initial positions. These actuator elements can be, for example, the magnetic valves of an antilocking brake system. The monitoring circuit checks, before excitation of a power supply relay, the connection of the relay to the power supply, the blocking condition of a switching transistor, through which the power supply relay (Rel) is activated, and the separating position of the power supply contact of the power supply relay. Moreover, the monitoring circuit responds to overvoltages.

Abstract: A circuit configuration for actuating a safety relay (1) such as the main relay of an electronically controlled brake system of an automotive vehicle at least has two transistors (T1, T2) connected in series and a monitoring circuit (5) which will urge the transistors into the non-conductive state if there is a defect or trouble. The operativeness of the transistors (T1, T2) or of the monitoring circuit (5) will cause the safety relay (1) to be switched off.

Abstract: A circuit configuration for editing, or processing the output signal of a speed sensor (5) includes a trigger circuit (1, 22), the changeover points or "hysteresis" of which are controllable, with the circuit configuration being furnished with circuits for determining the coupling factor (k), and with circuits for adjusting the hysteresis in response to the coupling factor. The coupling factor (k)--multiplied by the frequency of the sensor signal corresponding to the speed--forms the amplitude of the sensor output signal. With the coupling factor (k) being high, the hysteresis will be high, while it will be low with a low coupling factor.

Abstract: This is a circuit configuration provided for an anti-lock-controlled brake system and serving for processing sensor signals obtained by wheel sensors (5) and for generating braking pressure control signals. This circuit configuration contains two microcontrollers (1, 2) interconnected by data exchange lines (7). The handled signals are concurrently processed by the microcontrollers independently of one another and the exchanged signals are checked for consistency. A deviation of the exchanged signals which is due to malfunctions is signalized to a safety circuit (8) which, thereupon, interrupts the power supply to the solenoid valves (Ll . . . Ln). The monitoring signal (WD1, WD2) fed to the safety circuit (8) is a predetermined alternating signal in case of consistency of the exchanged signals and in case of proper operation of the circuit configuration.

Abstract: A circuit configuration for monitoring the final stages of a plurality of valves, particularly the power transistors (LT1-LT4) and their circuitry, for defects as well as for leakage currents or by-path currents comprises a comparator circuit (1), an OR-link (2) and of a further comparator element (XOR4). By way of the monitoring circuit, the actuation connections (S1-S4) of electromagnetically operable valves are connected to a sole output (A3). By applying short test pulses to the actuation inputs (E1-E4) of the final stages (LT1-LT4) and by comparing the signal variation at the output (A3) with the test pulse variation defects, leakage currents and the like are detected.

Abstract: To process the output signal of a rotational speed sensor (2) which generates an alternating voltage dependent in respect of frequency and amplitude on the rotational speed, two low-pass filters (TP1, TP2) serve to produce a useful signal (I1), on the one hand, and a reference signal (I2), on the other hand. The two signals are compared. In dependence on the difference of these signals (I1, I2) a pulse-shaped output signal, namely the processed sensor signal, is generated by means of a comparator (7). The reference signal dynamically follows the useful signal with the aid of a control signal issue by an adapter circuit (20,21).