Patents Assigned to STMicroelectronics S.r.l.
  • Publication number: 20020054682
    Abstract: A method to protect the contents of an electronic document through an encryption system based on an initial confusing step in a scrambler and a subsequent diffusion step in a chaotic processor, both steps being of a chaotic type. Initially, encryption keys and an initial chaotic value are acquired; input character strings are acquired; and diffused character strings are calculated using the input character strings, the encryption keys, and previous diffused character strings. After a certain number of iterations, sets of diffused character strings are added to subsequent chaotic values generated by a chaotic processor to obtain encrypted words. Decryption is obtained through two successive operations, wherein the encrypted words are added to chaotic values identical to the encryption values and subtracted from previously decrypted words using an unscrambler element having a structure similar to that of the scrambler and using identical encryption keys.
    Type: Application
    Filed: August 8, 2001
    Publication date: May 9, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Giovanni Di Bernardo, Manuela La Rosa, Eusebio Di Cola, Luigi Occhipinti
  • Publication number: 20020054505
    Abstract: The data management method applies to a multilevel nonvolatile memory device having a memory array formed by a plurality of memory cells. Each of the memory cells stores a number of bits that is not an integer power of two, for example three. In this way, one data byte is stored in a non-integer number of memory cells. The managing method includes storing, in a same clock cycle, a data word formed by a plurality of bytes, by programming a preset number of adjacent memory cells. Reading is performed by reading, in a same clock cycle, the stored data word.
    Type: Application
    Filed: October 11, 2001
    Publication date: May 9, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Rino Micheloni, Giovanni Campardo
  • Publication number: 20020055249
    Abstract: An integrated device comprises a first conductive region and a first insulating region of dielectric material covering the first conductive region. A first through region of electrically conductive material extends inside the first insulating region, and is in direct electrical contact with the first conductive region. A second conductive region, arranged above the first insulating region, is in a position not aligned and not in contact with the first through region. A second insulating region of dielectric material covers the second conductive region. A second through region of electrically conductive material extends inside the second insulating region as far as the first through region and is aligned and in direct electrical contact with the first through region. A third conductive region, arranged above the second insulating region, is aligned and in direct electrical contact with the second through region.
    Type: Application
    Filed: October 24, 2001
    Publication date: May 9, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventor: Federico Pio
  • Patent number: 6384585
    Abstract: The present invention refers to a current generator able to provide in alternative to a first terminal a first current and a second current in response to a control signal. Particularly it refers to a current generator usable for the adaptive biasing of modulators of the sigma-delta type. In an embodiment the current generator is able to provide in alternative to a first terminal (70) a first current and a second current in response to a control signal (CK), characterized by comprising: a first current generator (40) able to provide said first current; a second current generator (41) able to provide said second current; commutation means (46) able to connect in alternative to said first terminal (70) said first current and said second current in response to said control signal (CK).
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: May 7, 2002
    Assignee: STMicroelectronics, S.R.L.
    Inventors: Paolo Cusinato, Andrea Baschirotto, Vittorio Colonna, Gabriele Gandolfi
  • Patent number: 6384645
    Abstract: An integrated circuit for producing a small slope voltage ramp includes a circuit for generating a periodic triangular current signal, and a circuit for generating, at the beginning of each period of the triangular signal, a pulse of a certain duration which is much smaller than the period of the triangular signal. A control loop is input at a node with the triangular current signal and produces the desired slow voltage ramp on the output node. The control loop includes a first hold circuit coupled to the input node via a first switch controlled by the pulse, and a transconductance operational amplifier, whose inputs are respectively coupled to the input node and to the output node. Also, the control loop includes a second hold circuit coupled to the output of the operational transconductance amplifier via a second switch controlled in a complementary manner with respect to the first switch.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: May 7, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Davide Brambilla, Mauro Cleris
  • Patent number: 6385067
    Abstract: A feedback control circuit is for the current in a load formed by a winding in series with a current sensing resistor, coupled to a full-bridge output stage, an amplifier coupled to the terminals of the sensing resistor, and a controller fed with the output of the amplifier and with a voltage reference and producing a correction signal. The circuit has a PWM converter for generating a pair of control signals. The PWM converter includes an up/down counter producing a count value and logic circuitry that produces the twos-complement of the correction signal. A pair of registers are coupled to the outputs of the controller and of the logic circuitry. A first comparator coupled to the outputs of the counter and of the first register produces the first control signal, if the count signal exceeds the value stored in the first register. A second comparator coupled to the counter and to the second register produces the second control signal, if the count signal overcomes the value stored in the second register.
    Type: Grant
    Filed: March 21, 2001
    Date of Patent: May 7, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Ezio Galbiati, Maurizio Nessi, Marco Palestra
  • Patent number: 6385107
    Abstract: An architecture handles internal voltages in a non-volatile memory array which is split into at least first and second mutually independent banks. The architecture includes first and second pluralities of generators for generating at least one of the internal voltages, which are separate from each other and connected to the first and second banks, respectively, of the nonvolatile memory array; and a control system connected to the pluralities of generators to handle the correct activation of the different generators in the different conditions of the memory array operation.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: May 7, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Lorenzo Bedarida, Simone Bartoli, Mauro Sali, Antonio Russo
  • Publication number: 20020052857
    Abstract: An optimized method of computing the value of the degree of membership of a fuzzy variable defined within a universe of discourse that is discreted into a finite number of points by way of a membership function thereof, wherein the membership function is quantified into a finite number of levels corresponding to a finite number of degrees of truth, and is stored as a characteristic value of each subset of fuzzy variable values being all mirrored in one value of said degree of membership corresponding to one of said levels. The computing method includes generating a binary sequence; generating an address signal from the bits in the binary sequence; reading the contents of the memory storing the membership functions at each address signal to obtain a characteristic value; and comparing the characteristic value with the value of a fuzzy input variable.
    Type: Application
    Filed: October 1, 2001
    Publication date: May 2, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Francesco Pappalardo, Biagio Giacalone
  • Publication number: 20020052541
    Abstract: A portable system carried by a user for assessing movement of the user includes at least one motion sensor adjacent a portion of the user's body under observation. An analog-to-digital converter is connected to the motion sensor for converting an analog signal therefrom into a digital signal. A logic circuit is connected to the analog-to-digital converter for calculating parameters based upon the digital signal. A first fuzzy logic processing circuit is connected to the logic circuit for processing the calculated parameters and for generating corresponding fuzzy classification labels based upon movement of the portion of the user's body under observation during an interval of time. A memory is connected to the first fuzzy logic processing circuit for storing at least one of the calculated parameters and the fuzzy classification labels.
    Type: Application
    Filed: April 3, 2001
    Publication date: May 2, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Antonino Cuce, Maria Cassese, Davide Platania
  • Publication number: 20020050811
    Abstract: The invention relates to a circuit generating a voltage signal which is independent of temperature and has low sensitivity to variations in process parameters, comprising at least an output MOS transistor through which an output current flows, it being connected to a first voltage reference and having a gate terminal connected to a bias network, in turn connected between a second voltage reference and the first voltage reference. The circuit of this invention includes a bias network comprising at least first and second MOS transistors connected in a diode configuration, connected in series between said first and second voltage references, and connected to the second voltage reference through a current generator element having a thermal gradient that approximates the thermal gradient of a MOS transistor.
    Type: Application
    Filed: August 1, 2001
    Publication date: May 2, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventor: Claudio Serratoni
  • Patent number: 6380582
    Abstract: Self-aligned etching process for providing a plurality of mutually parallel word lines in a first conducting layer deposited over a plagiarized architecture obtained starting from a semiconductor substrate on which is provided a plurality of active elements extending along separate parallel lines e.g., memory cell bit lines and comprising gate regions made up of a first conducting layer, an intermediate dielectric layer and a second conducting layer with said regions being insulated from each other by insulation regions to form said architecture with said word lines being defined photolithographically by protective strips implemented by means of: a vertical profile etching for complete removal from the unprotected areas of the first conducting layer of the second conducting layer and of the intermediate dielectric layer respectively, and a following isotropic etching of the first conducting layer.
    Type: Grant
    Filed: March 17, 2000
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Emilio Camerlenghi, Elio Colabella, Luca Pividori, Adriana Rebora
  • Patent number: 6380592
    Abstract: A semiconductor memory cell that includes a word line, two bit lines, a precharge line, and two cross-coupled inverters. Each of the inverters is formed by a P-channel transistor and an N-channel transistor. Additionally, a first access transistor selectively couples one bit line to the output of one inverter, and a second access transistor selectively couples the other bit line to the output of the other inverter. One terminal of the N-channel transistor of each of the inverters is connected to the precharge line. In a preferred embodiment, the access transistors are P-channel transistors and the gate terminal of each PMOS access transistor is connected to the word line. Additionally, the present invention provides a method of writing data to a semiconductor memory cell that is connected to a pair of bit lines.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Michael Tooher, Stefano Tonello
  • Patent number: 6381177
    Abstract: A method for controlled soft programming of a plurality of non-volatile memory cells, having bulk terminals connected to one another and to a common bulk line. The method includes supplying at least one soft programming pulse to the plurality of memory cells for a time interval. In this step, a bulk voltage with a rising negative ramp is applied to the common bulk line for the time interval. By this means, the threshold voltage of the cells is increased by body effect, and initially only the most depleted cells are soft programmed, with a limited drain current. Subsequently, when the bulk voltage increases, the cells with a higher threshold voltage are also soft programmed, until all the cells have reached the required minimum threshold value.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Guido De Sandre, Marco Pasotti, Pier Luigi Rolandi
  • Patent number: 6381173
    Abstract: A serial-flash, EPROM, EEPROM, or flash EEPROM nonvolatile memory in AMG configuration includes a byte enable transistor having an input terminal, connected to a control gate line and receives an input voltage, an output terminal, connected to at least one memory cell and supplying an output voltage, a control terminal connected to a word line, and a bulk region housing conductive regions connected to the input and output terminals. The byte enable transistor is a P-channel MOS transistor, the bulk region whereof is biased to a bulk voltage that is not lower than the input voltage.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventor: Nicola Zatelli
  • Patent number: 6380034
    Abstract: A manufacturing process including: forming a substrate and insulating layer including a tunnel area; and simultaneously forming a floating gate region of a memory transistor and a lower gate portion of a selection transistor, the floating gate region internally forming a hole, one side of which delimits, together with an external side of the floating gate region, a portion of tunnel arranged above the tunnel area; a dielectric material layer is then deposited, and fills the hole of the floating gate region; the structure is planarized by CMP, and an insulating region of dielectric material is formed; and a control gate region is formed above the floating gate region and simultaneously an upper gate portion is formed above the lower gate portion. The upper and lower gate portions form a control gate region of the selection transistor. In this way, the upper gate portion and the control gate region are substantially on the same level.
    Type: Grant
    Filed: July 20, 2000
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Bruno Vajana, Giovanna Dalla Libera
  • Patent number: 6381185
    Abstract: A method for testing a programmable, nonvolatile memory including a matrix of memory cells is provided. A plurality of memory cells are programmed. The programmed memory cells are addressed in succession to identify a lowest of threshold voltage levels. The addressing for each memory location includes applying a selection voltage that is lower than the lowest threshold voltage level corresponding to a memory location currently being addressed. The bits are read from the programmed memory cells for the memory location currently being addressed. The reading is repeated while progressively changing the selection voltage supplied to the word line corresponding to the memory location currently being addressed until it is detected that at least one of the bits of the memory location currently being addressed has switched from a first logic level corresponding to a reading of a programmed memory cell to a second logic level corresponding to a reading of a non-programmed memory cell.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: April 30, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Alessandro Camera, Paolo Sandri, Ignazio Bellomo, Albino Pidutti
  • Publication number: 20020047695
    Abstract: A switching regulator circuit produces a varying reference voltage with temperature and includes at least one band-gap generator for supplying a power stage through an error amplifier and a comparator. The error amplifier is also supplied a regulated voltage which may be produced by the regulator itself. The at least one band-gap generator includes a plurality of band-gap generators being supplied by the regulated voltage and input a fraction of the regulated voltage through a voltage divider. The respective outputs of the band-gap generators are connected to a logic network which has an output connected to the power stage. The error amplifier and comparator may be included within each respective band-gap generator.
    Type: Application
    Filed: August 30, 2001
    Publication date: April 25, 2002
    Applicant: STMicroelectronic S.r.l.
    Inventor: Franco Cocetta
  • Patent number: 6376291
    Abstract: A process of forming on a monocrystalline-silicon body an etching-aid region of polycrystalline silicon; forming, on the etching-aid region a nucleus region of polycrystalline silicon surrounded by a protective structure having an opening extending as far as the etching-aid region; TMAH-etching the etching-aid region and the monocrystalline body to form a tub-shaped cavity; removing the top layer of the protective structure; and growing an epitaxial layer on the monocrystalline body and the nucleus region. The epitaxial layer, of monocrystalline type on the monocrystalline body and of polycrystalline type on the nucleus region, closes upwardly the etching opening, and the cavity is thus completely embedded in the resulting wafer.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: April 23, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Gabriele Barlocchi, Flavio Villa, Pietro Corona
  • Patent number: 6376306
    Abstract: An improved method of making semiconductor memory structures that include a memory matrix having non-volatile memory cells, each with a floating gate transistor and a selection transistor, each transistor provided with a gate electrode. Associated with the memory matrix is control circuitry, which also have control gates. The method includes forming the gate electrodes on top of the semiconductor substrate and then depositing a dielectric layer over the whole memory structure. A screening layer is deposited over the whole surface of the memory structure, and then part of it is removed, exposing a portion of the control circuitry. A portion of the dielectric layer is etched away in the non-covered portion of the control circuitry to form spacer regions, and the non-covered portion of the control circuitry is then implanted with a dopant.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: April 23, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Elio Colabella, Emilio Camerlenghi
  • Publication number: 20020044463
    Abstract: The power supply device comprises a DC-DC converter circuit including a power switch and a driving stage. The driving stage has a compensation terminal on which a compensation voltage is present and which receives a biasing current, said driving stage comprising a control circuit having an output terminal connected to a control terminal of the power switch and disconnection-detecting means connected to said compensation terminal and generating a signal for permanent turning-off of said power switch when the biasing current drops below a current-threshold value. The driving stage moreover comprises over-voltage detecting means connected to the compensation terminal and generating a signal for temporary turning-off of said power switch when said compensation voltage exceeds a voltage-threshold value.
    Type: Application
    Filed: July 30, 2001
    Publication date: April 18, 2002
    Applicant: STMicroelectronics S.r.l.
    Inventors: Gregorio Bontempo, Claudio Adragna, Mauro Fagnani, Albino Pidutti, Francesco Pulvirenti, Roberto Quaglino, Giuseppe Gattavari