Abstract: An integrated cell for extracting a binary value based on a value difference between two resistors values, including connection circuitry for a binary reading of the sign of the difference between the resistors, and connection circuitry for a modification of the value of one of the resistors to make the sign of the difference invariable.

Abstract: An electromagnetic transponder intended to draw the power necessary to its operation of from a field radiated by a terminal of transmission of a carrier at a first supply frequency and to back-modulate the received signal at the rate of a sub-carrier at a second frequency lower than the first one, and comprising means capable of demodulating and decoding signals modulated by said sub-carrier, as well as a system of communication between such transponders.

Abstract: A method for manufacturing an electronic tag to be affixed onto a product includes providing, in an electrically conductive film of a foil for packaging, packing or transporting the product, areas devoid of any electrically conductive material for delimiting in the electrically conductive film at least one antenna pattern for forming an antenna for an RFID tag. A semiconductor chip is connected to the antenna for forming an electronic tag.

Abstract: A circuit and method for supplying an electronic circuit with a direct supply voltage using high frequency antenna signals. The method includes producing a primary direct voltage equal to a fraction of the supply voltage using at least one antenna signal, producing at least two pumping signals having a frequency lower than the frequency of the antenna signals by means of an oscillator electrically powered by the primary voltage and boosting the primary voltage by means of a charge pump driven by the pumping signals, to obtain the supply voltage.

Abstract: A method for executing a write command for writing a binary word in a programmable memory, comprises writing each of the bits in a programmed state of a binary word to be written in a corresponding memory cell of the memory, reading each bit of the word written in the memory corresponding to a bit in the programmed state of the word to be written, comparing each bit in the programmed state of the word to be written with a corresponding bit read in the memory, and generating an error signal if at least one bit of the word to be written in the programmed state is different from the corresponding bit read. Application of the method can be particularly but not exclusively to integrated circuits for chip cards.

Abstract: A method divides a number N1 by a number which can be written in the form 2n/k, n and k being whole numbers, and obtains a result N2. The result N2 is calculated by adding terms N1*Ki/2n-i for i ranging from 0 to N, the terms Ki being the constituent bits K0, K1, K2, . . . KN-1 of the number k expressed in binary. The method can be applied particularly to the production of a calibration circuit for calibrating a clock signal in a UHF transponder.

Abstract: The invention concerns a demodulator of an amplitude-modulated signal (Vdb), characterised in that it comprises a peak detecting cell (DCR) capable of extracting the reference modulating signal (Vpeak1) of the modulated signal (Vdb); a first demodulator (FE) adapted to detect the peak of the reference modulating signal (Vpeak1) to generate a high comparison threshold and locate the start of the modulation, a second demodulator (RE) adapted to detect a trough of the reference modulating signal (Vpeak1) to generate a low comparison threshold and locate the end of the modulation; a logic processing unit capable of supplying the demodulated signal (Vdemod).

Abstract: A method for generating a variable number includes generating a clock signal, demodulating a received signal of data transmission, supplying a binary signal having variable frequency pulses, and sampling the clock signal by the binary signal to generate bits of a variable number. The method can be applied to RFID tags.

Abstract: A method protects against a global data erasure an integrated circuit comprising an electrically programmable data memory and a control unit to execute commands for reading or writing in the memory. The method comprises the steps of providing, in the integrated circuit, electrically programmable reference memory cells, at putting the integrated circuit into service, storing, in the reference memory cells, bits of determined value forming an authorized combination of bits and, during the operation of the integrated circuit following its putting into service, reading and evaluating the reference memory cells and blocking the integrated circuit if the reference memory cells contain a forbidden combination of bits different from the authorized combination.

Abstract: A method checks the state of a set of memory cells of a memory comprising memory cells arranged in a memory array, means for selecting a memory cell, and a sense amplifier for supplying a state of the selected memory cell depending on whether the selected memory cell is conductive or non-conductive. The method includes features wherein all the memory cells of a set grouping together several memory cells are selected, and then simultaneously coupled to the sense amplifier, and the sense amplifier supplies a global state of all the selected memory cells to which it is coupled, if the latter are simultaneously non-conductive. Application is provided to the checking of a command for block-erasing a memory.

Abstract: A dual-mode smart card comprising several pads of physical contact with an external reader and two pads of connection to an antenna for a contactless operation, and comprising a voltage regulator capable of extracting from a radio frequency excitation reaching the antenna, a supply voltage of the chip's processing circuits, this regulator being controllable by a central circuit to be deactivated in the presence of a supply voltage on contacts of the chip.

Abstract: A method of reading a group of memory words from an integrated circuit memory of a contactless tag, comprising the sending by a remote interrogation unit to the contactless tag of a specific command for reading the group of memory words from a given start address, the initialization of an address counter for the contactless tag to the value of the given start address, and the sending by the contactless tag of the memory word at the start address, as well as an iterative process comprising in succession a first step of sending by the remote interrogation unit to the contactless tag of an incrementation marker recognizable by the contactless tag, a second step of incrementation of the address counter for the contactless tag in response to the incrementation marker, and a third step of sending by the contactless tag to the remote interrogation unit of a data frame comprising the memory word stored in the memory at the address pointed at by the current value of the address counter.

Abstract: An electromagnetic transponder and a method for controlling by pulse trains a switch for modulating the load of this transponder in an electromagnetic field from which it extracts its power supply, the duty ratio of the pulses being controlled according to the transponder supply voltage.

Abstract: The invention relates to a memory cell with a binary value consisting of two parallel branches. Each of said branches comprises: at least one polycrystalline silicon programming resistor (Rp1, Rp2), which is connected between a first supply terminal (1) and a point or terminal for the differential reading (4, 6) of the memory cell state; and at least one first switch (MNP1, MNP2) which, during programming, connects one of said read terminals to a second supply terminal (2).

Abstract: A power-on reset device for an electronic circuit includes an output terminal for delivering a reset signal. The reset signal may be active or inactive as a function of a supply voltage. A comparison node is coupled to the output terminal by way of at least one inverter. A first current source assembly delivers a first current to charge or discharge the comparison node. The first current is dependent on the supply voltage and on a specified current value, and is at maximum equal to this specified value. A second current source assembly delivers a second current to discharge or charge the comparison node. This second current is substantially independent of the supply voltage.

Abstract: A memory for a contactless tag of the RFID type is configured to receive a deactivation command. The memory includes a group of memory words that are suitable for storing an identifier of the tag and are write-accessible via a standard write command. The memory further includes at least one additional memory word suitable for storing a deactivation value. The detected presence of the deactivation value makes it possible for the tag to prevent reading and/or the transmission of the identifier in response to a radio interrogation signal.

Abstract: A demodulator for an amplitude modulated alternating signal includes a peak detection circuit for extracting the reference modulating signal from the amplitude modulated alternating signal, and a first translation circuit for offsetting the level of the reference modulating signal by a value equal to the DC component to obtain an offset reference modulated signal. A comparison threshold generator circuit generates a comparison threshold to locate the start and the end of the modulation, and a comparator circuit compares the offset reference modulating signal with the comparison threshold for providing signals that cross the comparison threshold. An unregulated supply circuit provides a supply voltage to the different circuits.

Abstract: An electromagnetic transponder intended to draw the power necessary to its operation of from a field radiated by a terminal of transmission of a carrier at a first supply frequency and to back-modulate the received signal at the rate of a sub-carrier at a second frequency lower than the first one, and comprising means capable of demodulating and decoding signals modulated by said sub-carrier, as well as a system of communication between such transponders.

Abstract: The invention concerns a method for making an integrated electronic component arranged on a substrate wafer comprising at least two met allising steps. The invention is characterised in that the value of an electrical parameter of the component is determined after a metallising step, and one of the following metallising processes is carried out with an adjusting mask selected among n predefined masks to obtain a desired value of the parameter, the selection of the adjusting mask being performed in accordance with the predetermined value of the electrical parameter.

Abstract: A demodulator for an amplitude modulated alternating signal includes a peak detection circuit for extracting the reference modulating signal from the amplitude modulated alternating signal, and a first translation circuit for offsetting the level of the reference modulating signal by a value equal to the DC component to obtain an offset reference modulated signal. A comparison threshold generator circuit generates a comparison threshold to locate the start and the end of the modulation, and a comparator circuit compares the offset reference modulating signal with the comparison threshold for providing signals that cross the comparison threshold. An unregulated supply circuit provides a supply voltage to the different circuits.