Abstract: The invention concerns a device for measuring a radiofrequency magnetic field, characterised in that it comprises on a common support: a coil forming a primary reception antenna; a voltage-controlled oscillator, monitored so that its output frequency depends on the amplitude of the magnetic field received on the coil forming primary antenna; an absorption modulation load connected to the oscillator output; a secondary antenna sensitive to the magnetic field influenced by the absorption modulation resulting from the power supply load by the voltage-controlled oscillator, and means for operating the available signal on the secondary antenna.

Abstract: The invention concerns a device for measuring a radiofrequency magnetic field, characterised in that it comprises on a common support (10): a coil forming a primary reception antenna; a voltage-controlled oscillator, monitored so that its output frequency depends on the amplitude of the magnetic field received on the coil forming primary antenna; an absorption modulation load connected to the oscillator output; a secondary antenna (22) sensitive to the magnetic field influenced by the absorption modulation resulting from the power supply load by the voltage-controlled oscillator, and means (30) for operating the available signal on the secondary antenna (22).

Abstract: The invention concerns a device for measuring a radiofrequency magnetic field, characterised in that it comprises on a common support: a coil forming a primary reception antenna; a voltage-controlled oscillator, monitored so that its output frequency depends on the amplitude of the magnetic field received on the coil forming primary antenna; an absorption modulation load connected to the oscillator output; a secondary antenna sensitive to the magnetic field influenced by the absorption modulation resulting from the power supply load by the voltage-controlled oscillator, and means for operating the available signal on the secondary antenna.

Abstract: The invention concerns a device for measuring a radiofrequency magnetic field, characterised in that it comprises on a common support (10): a coil forming a primary reception antenna; a voltage-controlled oscillator, monitored so that its output frequency depends on the amplitude of the magnetic field received on the coil forming primary antenna; an absorption modulation load connected to the oscillator output; a secondary antenna (22) sensitive to the magnetic field influenced by the absorption modulation resulting from the power supply load by the voltage-controlled oscillator, and means (30) for operating the available signal on the secondary antenna (22).

Abstract: A micro-electronic component for a portable object is of the type which incorporates digital processing means, and an interface for contact-free electromagnetic coupling with a remote station. The digital processing means can operate according to an operating mode of the request/acknowledgement type, which is substantially insensitive to the propagation time, without a global, regular clock. The component additionally comprises adapter means, which can adapt the signals of the contact-free interface to the signals of the digital processing means and vice versa, in order to permit two-way dialogue with the remote station.

Abstract: The invention relates to a stabilized power supply device for an assembly of remotely powered electronic components, for which the supply and the data transmission take place on the same channel. The device includes an electronic module which is interposed between the supply channel and the assembly of electronic circuits, supplies the said assembly of electronic components with a variable current in order for the proper operation of the said assembly of electronic components to be satisfied, and consumes a constant current in order to allow effective data transmission.

Abstract: In one embodiment, the voltage rectifying device includes two input terminals for an AC voltage, rectifying means made using integrated technology within a semiconductor substrate, and two output terminals for a rectified voltage, one of these output terminals being taken out at substrate level. The rectifying means may include a pair of first insulated-gate field-effect transistors connected as diodes with one of their electrodes linked to the substrate, and a pair of second insulated-gate field-effect transistors arranged respectively in biased semiconductor wells with the gates linked and crossed over the two input terminals, the first and second transistors having channels of opposite types and a drain/source voltage when conducting which is below a predetermined voltage.

Abstract: A memory card, capable of remotely exchanging information with a terminal by modulating a magnetic field generated by said terminal, includes a voltage limiter (LMT) with an input terminal (BE) for receiving, during the transmission of information between the terminal and the card, an amplitude modulated voltage (VNR) with a time-varying average voltage level (NM). A primary transistor (TZ1) is connected between the input terminal and ground. Diodes (D1. . . DN) are series connected between the input terminal (BE) and ground and between the input terminal (BE) and the gate of the primary transistor (TZ1), wherein the threshold voltages of the diodes and primary transistor define a limit value for the input voltage. A capacitor (C) is connected between the primary transistor gate and ground.

Abstract: A component comprises a coil for the supply by induction of the component and for the inductive bidirectional transfer with the station of a signal representative of data. Means for processing said signal are supplied by the coil and are produced in integrated technology on the substrate of the component. The turns of the coil are produced in flat integrated technology by metallization on the surface of the component. The integral coil occupies at least 50% of the total surface of the component.

Abstract: The device comprises, connected to the antenna, a rectifier (RD) delivering a primary DC supply voltage (VNR) at its output terminal (BS), stabilizing means (1,ST) for generating a stabilized DC voltage (VDD) from the said primary voltage. First means (R3, R4, R5) calculate a first prespecified voltage threshold corresponding to a prespecified level of the stabilized DC supply voltage. Comparison means (CP) are also provided, the output terminal (BS2) of which is connected to the processing means, a first input of which is connected to the output of the first calculating means, and a second input of which is connected to the output terminal (BS) of the rectifier. Furthermore, a load (RBL) with chosen impedance is connected between the said output terminal of the rectifier and earth by way of a controllable switching means (T200) whose control input is joined to the output terminal of the comparison means (CP).

Abstract: The phase-locked loop includes means (3) for generating an internal signal (SIN) drawn from the output signal of the voltage-controlled oscillator (2), and a phase comparator (4) able to compare the phase of the internal signal (SIN) with that of an external signal received (SSY), and the output of which is looped back onto the voltage-controlled oscillator (2). It further comprises a device (6) accelerating the synchronization of the internal and external signals, including processing means able to receive, from the phase comparator (4), a predetermined indication representative of the non-coincidence of the internal and external signals, and, in response to this predetermined indication, to deliver control information in response to which the generation means (3) modify the phase of the internal signal in order to force the latter substantially into phase with the external signal (SSY).

Abstract: A component comprises a coil for the supply by induction of the component and for the inductive bidirectional transfer with the station of a signal representative of data. Means for processing said signal are supplied by the coil and are produced in integrated technology on the substrate of the component. The turns of the coil are produced in flat integrated technology by metallization on the surface of the component. The integral coil occupies at least 50% of the total surface of the component.