Abstract: A vehicle security arrangement includes at least one functional control unit, which provides a first code word; a theft protection control unit, which is coupled via a bus to the at least one functional control unit; and at least one input unit, which transmits to the theft protection control unit a second code word which the theft protection control unit forwards to the at least one function control unit. The theft protection control unit may initiate the provision of the first code word and the second code word. In the at least one functional control unit, a comparison of the first code word of the at least one functional control unit with the second code word takes place. In case of agreement between the first code word and the second code word, the at least one functional control unit enables itself.

Abstract: A method for preventing misuse of a transponder left inside a vehicle, which is part of a keyless vehicle access system and coacts with a control system for access and driving authorization located in the vehicle. The control system emits, in response to a locking command, a check signal by way of which it is ascertained whether transponders are still located in the vehicle interior after locking. Transponders which are detected as being located in the vehicle interior after locking are recorded in a memory associated with the control system. Upon a subsequent legitimate access to the vehicle, transponders that are not again detected in the interior are inhibited.

Abstract: A circuit arrangement for converting a DC voltage into another DC voltage, with simultaneous regulation of the emittable voltage (U.sub.A) at a predetermined value. The circuit arrangement includes a combination of an upward and a downward transformer having at least one switching transistor (3) connected in series with a common memory coil (1) to a circuit output terminal, and a smoothing capacitor (5) connected in parallel to the output load (6), i.e., across the output terminals. The coil (1) is connected for a specific time to the supply voltage source (U.sub.Bat) by a time function circuit (9, 10). The coil (1) is connected directly to the positive pole (+) of the supply-voltage source (U.sub.Bat), and a current limiter circuit is provided in the long or forward branch of the circuit arrangement in front of the output of the circuit arrangement, with the current limiter circuit comprising a resistor (4) and a transistor (15) and influencing the switching transistor (3) disposed in the long branch.

Abstract: A control system is provided for an internal combustion engine in a motor vehicle in which a potentiometer (11) responsive to the position of an accelerator pedal (12) provides a desired position signal to a comparator (15) controlling actuating signals to a servo motor (17) actuating a butterfly valve (18) and a second potentiometer (20) responsive to the position of the butterfly valve (18) provides a feedback signal to the comparator (15). The control system includes a safety device (24) controlling the fuel supply and/or ignition system, a third potentiometer (25) responsive to the position of the accelerator pedal (12), a fourth potentiometer (29) responsive to the position of the butterfly valve (18), and two threshold value switches (TS1,TS2) responsive respectively to the signals from the third and fourth potentiometers (25, 29) and providing output signals when such signals are respectively at or above a first predetermined voltage (V.sub.1), and below a second predetermined voltage (V.sub.2).

Abstract: An interface for use between a first communication unit having a two-wire connection and a second communication unit having a single-wire connection includes a comparator (IC1) having a fixed potential (V.sub.(-)) at its inverting input and having its output connected to one of the two-wire connections while the potential (V.sub.(+)) applied to the non-inverting input is determined by a switching network (transistors T1 and T2 and resistors R2, R3, R4, R7, R12) responsive to the potential on the second of the two-wire connections and on the single-wire connection to enable the first communication unit to receive data from the second communication unit but not to receive self-transmitted data.

Abstract: The invention is directed to a system for electronically open-loop controlling or closed-loop controlling the power of an internal combustion engine of a motor vehicle with an electrically actuable actuator influencing the engine power. The adjustment of this actuator is undertaken in dependence on a predetermined and an actual value for producing a match between pregiven and actual values. With the disappearance of a previously detected electrical disturbance of the system, the function is again taken up in a delayed manner.

Abstract: In a device for controlling and regulating the current through an electric consumer with a bridge circuit, the consumer being located in one of its diagonals, four current control members of the logic level power MOSFET type are provided, a pair of voltage regulating circuits for the gate voltage supply and a pair of current control circuits for the gate voltage control being connected respectively, two of to the four current control members. Each of the voltage regulating circuits is assembled of a diode having its anode connected to a d.c. power source and to the collector of a N-P-N transistor and, via a resistor, to the base of the transistor and to the cathode of a Zener diode whose anode is connected to a terminal of the consumer. The emitter of the transistor is connected to the gate of the assigned current control member.