Patents by Inventor Sylvie Wuidart

Sylvie Wuidart has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20030117148
    Abstract: A method and a circuit for detecting variations of at least one environmental parameter of an integrated circuit, including evaluating a propagation delay of an edge in delay elements sensitive to variations of the environmental parameter, and comparing the present or measured delay with at least one reference value.
    Type: Application
    Filed: September 4, 2002
    Publication date: June 26, 2003
    Inventors: Sylvie Wuidart, Luc Wuidart, Michel Bardouillet, Pierre Balthazar
  • Publication number: 20020124183
    Abstract: Before a predetermined processing sequence, the integrated circuit detects the state of at least one timer. The circuit controls the activation of the timer if it is not activated, and disables itself if the timer is activated.
    Type: Application
    Filed: November 1, 2001
    Publication date: September 5, 2002
    Applicant: STMicroelectronics S.A.
    Inventors: Fabrice Marinet, Sylvie Wuidart
  • Publication number: 20020016890
    Abstract: A secured microprocessor includes a rights allocation system for the allocation, to programs executable by the microprocessor, of permanent access rights to certain zones of the memory array of the microprocessor. The rights allocation system confers, on a sub-program shared by at least two programs, temporary rights of access to certain memory zones. The temporary rights are allocated when the sub-program is called by one of the programs as a function of the program calling the sub-program. The rights allocation system provides libraries in a secured microprocessor without harming the integrity of the rights conferred on programs using the libraries.
    Type: Application
    Filed: June 20, 2001
    Publication date: February 7, 2002
    Applicant: STMicroelectronics S.A.
    Inventor: Sylvie Wuidart
  • Patent number: 6324653
    Abstract: An integrated circuit includes a microprocessor driven by an internal clock signal and at least one internal peripheral circuit activated selectively by the microprocessor to perform an operation, wherein said circuit includes a circuit for matching the period of the internal clock signal to the operating time of the activated internal peripheral circuit. The integrated circuit can be used as part of any microcontroller.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: November 27, 2001
    Assignee: STMicroelectronics S.A.
    Inventors: Mathieu Pierre Gabriel Lisart, Sylvie Wuidart
  • Patent number: 5994917
    Abstract: A method and apparatus for sequencing an integrated circuit which receives an external clock signal consists of the use of an internally generated random clock signal and of the use of either of these clock signals depending on the instruction to be performed.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: November 30, 1999
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Sylvie Wuidart
  • Patent number: 5948102
    Abstract: Disclosed is a method and apparatus to increase the security of an integrated circuit, the integrated circuit including at least one microprocessor, one or more security sensors to detect abnormal conditions of operation, and registers accessible by the microprocessor which store a state of a respective sensor. The microprocessor reads the contents of a register only at the end of a random period where the duration of the random period is determined by a number generated by a random number generator.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: September 7, 1999
    Inventor: Sylvie Wuidart
  • Patent number: 5912859
    Abstract: A method for the resetting of a group of series-connected non-transparent synchronous memory cells. The method includes modifying the clock signals that control the transfer gates of these cells on the activation of a resetting signal to set all the transfer gates in the on state. The method is particularly suited to the resetting of long shift registers such as those used in cryptographic applications, especially in micro-circuit cards, and the reset circuitry can be implemented using conventional logic gates.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: June 15, 1999
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Sylvie Wuidart
  • Patent number: 5892369
    Abstract: A method for detecting the presence of a passivation layer on an integrated circuit comprises sending out a train of pulses of different widths at one end of a line of metal that winds on the surface of the integrated circuit beneath the protection layer of the integrated circuit. The line of metal and the dielectric layer of the integrated circuit form an RC filter. The number of pulses received at the other end of the line of metal is counted and compared with at least one characteristic reference value of the filter.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: April 6, 1999
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Laurent Sourgen, Sylvie Wuidart
  • Patent number: 5850452
    Abstract: The present invention concerns a method for the numerical scrambling by permutation of data bits in a programmable circuit comprising a control unit and at least one data bus (DBUS) to transmit data between the control unit and several memory circuits. It consists of having data on the bus either in a scrambled form or in an unscrambled form according to whether it is instructions data or not. And data in some of the memories is scrambled. The present invention also concerns a method for realising a permutation circuit.
    Type: Grant
    Filed: July 31, 1995
    Date of Patent: December 15, 1998
    Assignee: STMicroelectronics S.A.
    Inventors: Laurent Sourgen, Sylvie Wuidart
  • Patent number: 5815030
    Abstract: A circuit for the filtering of a pulse signal comprises means to detect an output pulse upon the detection of an input pulse, the shape of this output pulse being based on elementary delays obtained by the charging and discharging of capacitors. During the generation of the output pulse, no new input pulse can be taken into account.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: September 29, 1998
    Assignee: SGS-Thomson Microelectronics, S.A.
    Inventors: Sylvie Wuidart, Tien-Dung Do
  • Patent number: 5781470
    Abstract: The present invention concerns a method for protecting a write operation of a memory cell within an integrated circuit that comprises the introduction of a random period (d1) between the reception of an external write command and the application of a physical variable to the memory cell so as to thwart the determination of the applied waveform characteristics as a function of time of this physical variable. The present invention also concerns an integrated circuit that comprises a memory whose write operation is protected according to this method. An application of the present invention is in the domain of chip carrying cards, i.e. smartcard applications.
    Type: Grant
    Filed: March 21, 1996
    Date of Patent: July 14, 1998
    Assignee: SGS-Thomson Microelectronics, S.A.
    Inventors: Laurent Sourgen, Sylvie Wuidart
  • Patent number: 5778037
    Abstract: A method for the resetting of a group of series-connected non-transparent synchronous memory cells. The method includes modifying the clock signals that control the transfer gates of these cells on the activation of a resetting signal to set all the transfer gates in the on state. The method is particularly suited to the resetting of long shift registers such as those used in cryptographic applications, especially in micro-circuit cards, and the reset circuitry can be implemented using conventional logic gates.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: July 7, 1998
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Sylvie Wuidart
  • Patent number: 5764653
    Abstract: In an integrated circuit, a detector of information coherency is associated with a circuit for the storage of information. The detector includes a reference circuit that has the same structure as the storage circuit. The reference circuit contains complementary information under normal circumstances. A checking circuit of the detector verifies the complementary nature of the information in the reference circuit and detects disturbing phenomena that cause incoherence in the information contained in the storage circuit.
    Type: Grant
    Filed: March 20, 1996
    Date of Patent: June 9, 1998
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Sylvie Wuidart
  • Patent number: 5714899
    Abstract: A circuit for the generation of a time-stabilized output pulse Iout comprises a capacitor biased by two completely independent voltages whose bias voltages are filed by a current generator through current mirrors and are therefore very stable.
    Type: Grant
    Filed: January 6, 1997
    Date of Patent: February 3, 1998
    Assignee: SGS-Thomson Microelectronics, S.A.
    Inventors: Sylvie Wuidart, Tien-Dung Do
  • Patent number: 5469100
    Abstract: A circuit for the generation of a time-stabilized output pulse Iout comprises a capacitor biased by two completely independent voltages whose bias voltages are fixed by a current generator through current mirrors and are therefore very stable.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: November 21, 1995
    Assignee: SGS Thomson Microelectronics, S.A.
    Inventors: Sylvie Wuidart, Tien-Dung Do
  • Patent number: 5467053
    Abstract: A circuit for the filtering of a pulse signal comprises means to detect an output pulse upon the detection of an input pulse, the shape of this output pulse being based on elementary delays obtained by the charging and discharging of capacitors. During the generation of the output pulse, no new input pulse can be taken into account.
    Type: Grant
    Filed: August 4, 1994
    Date of Patent: November 14, 1995
    Assignee: SGS-Thomson Microelectronics, SA
    Inventors: Sylvie Wuidart, Tien-Dung Do
  • Patent number: 5270562
    Abstract: Locking devices are made by using a floating gate cell which is put into a state of being never programmable electrically by placing a voltage limiter between its drain zone and the ground and between its source zone and the ground. The cell can no longer ever be programmed by ultra-violet rays because of the interposition of a metal pad above its control gate. A voltage limiter is made by using a Zener diode made by the joining, to the drain and source zones, of a zone with opposite doping, placed outside the channel zone and connected to the ground.
    Type: Grant
    Filed: November 15, 1991
    Date of Patent: December 14, 1993
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Sylvie Wuidart