Abstract: The device for ambient light compensation for use in optical sensors exposed to both useful light and ambient light comprises at least one first photodiode and at least one second photodiode, the at least one first photodiode being adapted to be exposed to substantially the same useful light and ambient light as the at least one second photodiode. The device further comprises a current mirror circuit having an input and an output, the at least one first photodiode being connected to the input of the current mirror circuit, and the at least one second photodiode being connected to the output of the current mirror circuit. The current mirror circuit comprises a lowpass filter connected between the input and the output of the current mirror circuit. The output of the current mirror circuit provides an output signal representing the useful signal compensated for ambient light.

Abstract: In an inductive position sensor for determining the position, particularly the rotation angle, of a movable element, at least two subsystems are provided, which each have second transmitting units with an actuating unit, an oscillating circuit on the movable element, and a receiving unit with an evaluating unit. According to the invention, it is provided that the operation of the individual subsystems is carried out alternately. Thus, if one subsystem is operating, all other subsystems are deactivated. In this way, all subsystems are individually operated in a consecutive manner. The synchronization required to do so is provided by a non-galvanic coupling of the subsystems, and in particular by an inductive coupling by way of preferably existing inductances of the subsystems.

Abstract: The device for ambient light compensation for use in optical sensors exposed to both useful light and ambient light comprises at least one first photodiode and at least one second photodiode, the at least one first photodiode being adapted to be exposed to substantially the same useful light and ambient light as the at least one second photodiode. The device further comprises a current mirror circuit having an input and an output, the at least one first photodiode being connected to the input of the current mirror circuit, and the at least one second photodiode being connected to the output of the current mirror circuit. The current mirror circuit comprises a lowpass filter connected between the input and the output of the current mirror circuit. The output of the current mirror circuit provides an output signal representing the useful signal compensated for ambient light.

Abstract: In an inductive position sensor for determining the position, particularly the rotation angle, of a movable element, at least two subsystems are provided, which each have second transmitting units with an actuating unit, an oscillating circuit on the movable element, and a receiving unit with an evaluating unit. According to the invention, it is provided that the operation of the individual subsystems is carried out alternately. Thus, if one subsystem is operating, all other subsystems are deactivated. In this way, all subsystems are individually operated in a consecutive manner. The synchronization required to do so is provided by a non-galvanic coupling of the subsystems, and in particular by an inductive coupling by way of preferably existing inductances of the subsystems.

Abstract: This radiofrequency interface device (1) for a transponder, comprises a coil (2) forming the antenna of the transponder and a voltage converting circuit (4) connected, on the one hand to the terminals (5, 6) of said coil (2) and, on the other hand, to continuous voltage supply terminals (V.sub.dd, V.sub.ss) of an integrated logic circuit (7) of the transponder, and is characterised in that the terminals (5, 6) of the coil (2) are connected to floating potentials with respect to the substrate of the transponder, so that none of the terminals (5, 6) of the coil (2) passes below the potential (V.sub.ss) of the substrate.