Patents Represented by Attorney Harry K. Seed and Berry LLP Ahn
  • Patent number: 5837554
    Abstract: An integrated circuit structure is disclosed wherein an EPROM cell has an active area formed by the same operations as are carried out to form a P region intended to contain an N-channel MOS transistor, source and drain regions formed by the same operations as are carried out to form the source and drain regions of said transistor, a control electrode consisting of an N+ region formed by the same operations as are carried out to form deep regions intended to contact buried N+ regions, and a floating gate electrode consisting of a layer of conductive material formed by the same operations as are carried out to form the gate electrodes of the MOS transistors in the integrated circuit. The EPROM cell can, therefore, be formed in a mixed integrated circuit with no need for purposely added processing steps.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 17, 1998
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Claudio Contiero, Tiziana Cavioni, Stefano Manzini
  • Patent number: 5638327
    Abstract: A flash-EEPROM memory array presenting a NOR architecture wherein the memory cells, organized in rows and columns and having drain regions connected to respective bit lines, source regions connected to a common source line, and control gate regions connected to respective word lines, present an asymmetrical structure wherein one of the source and drain regions presents a highly resistive portion to permit programming and erasing of the cells at different regions. The array includes bias transistors arranged in a row and each connected between a respective bit line and the common source line, for maintaining at the same potential the drain and source regions of the cells connected to the nonaddressed bit lines during programming, and so preventing spurious writing.
    Type: Grant
    Filed: March 28, 1995
    Date of Patent: June 10, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Marco Dallabora, Mauro L. Sali, Fabio Tassan Caser, Corrado Villa
  • Patent number: 5636249
    Abstract: A method of and an apparatus for phase synchronization of a bit rate clock signal generated in an RDS receiver with a digital RDS signal demodulated on the receiver side, in which both the bit rate clock signal and the RDS signal have the same bit rate. Upon turning on of the RDS receiver and/or switching over of the same to a transmitter receiving frequency different from that received so far, a control signal is generated which, upon occurrence of the next rising edge or, alternatively, of the next falling edge of the RDS signal, effects such a phase angle shift of the bit rate clock signal that the bit rate clock signal, starting from that occurrence, is in phase synchronism with the RDS signal.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: June 3, 1997
    Assignee: SGS-Thomson Microelectronics GmbH
    Inventor: Gerhard Roither
  • Patent number: 5627790
    Abstract: A device including a load connected by a selection circuit to a number of bit lines, and a load connected to a reference cell, for detecting the current in the selected bit line and in the reference cell. The load connected to the bit lines comprises a transistor, and the reference load comprises two current paths, each formed by one transistor. One of the two transistors is diode-connected, and the other is switchable by a switching network connected to the gate terminal of the respective transistor, for turning it off when only one reference current path is to be enabled, and for diode-connecting it when both the reference current paths are to be enabled.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: May 6, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Carla M. Golla, Marco Olivo, Silvia Padoan
  • Patent number: 5623216
    Abstract: An output buffer current slew rate control integrated circuit includes an output buffer having first, MOS-type transistor means for supplying a current to a load impedance. Current generator means generate a constant current and are activated upon switching of an input signal of the output buffer. The current generator means drive a control input of the first transistor means for driving the first transistor means with a driving voltage having a slew rate determined by the constant current.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: April 22, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Luigi Penza, Calogero Timineri
  • Patent number: 5621357
    Abstract: An AB class stage is described which comprises two complementary MOSFET final transistors connected in a push-pull manner between two supply terminals. In order to attain high linearity, low switching distortion, a high ratio between the maximum output current and the rest current, independence of the rest current from the temperature and manufacturing variables and a circuit simplicity, the circuits determining the rest current and those which provide current to the load are substantially independent of one another. More particularly, two transconductance amplifiers are provided which control the final transistors and are dimensioned so as to have zero output current in rest conditions, two voltage generators which determine the rest current and two resistors being connected between the gate electrodes of the final transistors and the supply terminals.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: April 15, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Edoardo Botti, Giorgio Chiozzi
  • Patent number: 5610421
    Abstract: An integrated circuit structure is disclosed wherein an EPROM cell has an active area formed by the same operations as are carried out to form a P region intended to contain an N-channel MOS transistor, source and drain regions formed by the same operations as are carried out to form the source and drain regions of said transistor, a control electrode consisting of an N+ region formed by the same operations as are carried out to form deep regions intended to contact buried N+ regions, and a floating gate electrode consisting of a layer of conductive material formed by the same operations as are carried out to form the gate electrodes of the MOS transistors in the integrated circuit.The EPROM cell can, therefore, be formed in a mixed integrated circuit with no need for purposely added processing steps.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: March 11, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Claudio Contiero, Tiziana Cavioni, Stefano Manzini
  • Patent number: 5605850
    Abstract: A low-noise PNP transistor comprising a cutoff region laterally surrounding the emitter region in the surface portion of the transistor. The cutoff region has such a conductivity is to practically turn off the surface portion of the transistor, so that the transistor operates mainly in the bulk portion. The cutoff region is formed by an N.sup.+ -type enriched base region arranged between the emitter region and the collector region.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: February 25, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventor: Flavio Villa
  • Patent number: 5606584
    Abstract: The current invention provides a timer circuit for timing a plurality of time periods. The timer circuit has a timing pulse input for receiving timing pulses; a set of state outputs being at a set of logic states, each logic state taking one of two logic values, the logic values of the set of logic states changing at each timing pulse; a plurality of timing outputs, each providing a signal at the expiry of a predetermined time period; and a resetting signal for resetting the timing circuit and for defining an initial set of logic states. The set of logic states follows a first sequence of sets of logic values, beginning at the initial set of logic values, wherein all of the logic states within each set are at a first logic value (1) except at least one logic state, which is at a second logic value (0), different state outputs carrying the excepted state(s) in each of the sets of logic values within the first sequence of sets of logic values.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: February 25, 1997
    Assignee: SGS-Thomson Microelectronics Limited
    Inventor: Robert Beat
  • Patent number: 5602786
    Abstract: A method for programming redundancy registers in a column redundancy integrated circuitry for a semiconductor memory device with columns of memory elements grouped together to form portions of a bi-dimensional array of memory elements. The column redundancy circuitry comprises a plurality of non-volatile memory registers wherein each register is associated with a respective redundancy column of redundancy memory elements and each register is programmable to store an address of a defective column and an identifying code for identifying the portion of the bi-dimensional array to which the defective column belongs. When being programmed, each non-volatile memory register is supplied with column address signals and with a first subset of row address signals. The column address signals carry the address of a defective column and the first subset of row address signals carry the identifying code.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: February 11, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Luigi Pascucci, Marco Olivo
  • Patent number: 5600594
    Abstract: A circuit device for measuring the threshold voltage distribution among electrically programmable, non-volatile memory cells, which device comprises a differential amplifier having a first input connected to a first circuit leg including at least one memory cell and a second input connected to a second or reference circuit leg, and circuit means effective to cause an unbalance in the values of the currents flowing in the reference leg. The device is connected between a first supply voltage reference and a second voltage reference, and said circuit means comprise a generator of a varying current as a function of the supply voltage which is associated with the reference leg.
    Type: Grant
    Filed: March 31, 1995
    Date of Patent: February 4, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Silvia Padoan, Marco Maccarrone, Marco Olivo
  • Patent number: 5600590
    Abstract: A process for the manufacture of an integrated voltage limiter and stabilizer component in a flash EEPROM memory device comprises a step of formation of an N type lightly doped well on a single-crystal silicon substrate; a step of formation of an active area on the surface of said N type well; a step of growth of a thin gate oxide layer over said active area; a step of implantation of a first heavy dose of N type dopant into said N type well to obtain an N type region; a step of implantation of a second heavy dose, higher than said first heavy dose, of N type dopant into said N type region to obtain an N+contact region to both the N type well and said N type region; a step of implantation of a third heavy dose, higher than said first heavy dose, of P type dopant into said N type region to form a P+ region.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: February 4, 1997
    Assignee: SGS-Thomson Microelectronics, S.r.l.
    Inventors: Paolo Ghezzi, Alfonso Maurelli
  • Patent number: 5597750
    Abstract: A circuit structure for a matrix of EEPROM memory cells, being of a type which comprises a matrix of cells including plural rows and columns, with each row being provided with a word line and a control gate line and each column having a bit line; the bit lines, moreover, are gathered into groups or bytes of simultaneously addressable adjacent lines. Each cell in the matrix incorporates a floating gate transistor which is coupled to a control gate, connected to the control gate line, and is connected serially to a selection transistor; also, the cells of each individual byte share their respective source areas, which areas are structurally independent for each byte and are led to a corresponding source addressing line extending along a matrix column.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Federico Pio, Carlo Riva, Silvia Lucherini
  • Patent number: 5592416
    Abstract: An electronic storage circuit for storing information, in particular switch control information for alternately switching circuit parts of integrated monolithic circuits, having two series connections inserted between the two poles of a voltage supply source each including an EPROM transistor and a MOS transistor, the control gates of the two EPROM transistors being connected jointly with a reference voltage source, and the gates of the two MOS transistors with the connection point of the EPROM transistor and the MOS transistor of the other series connection.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: January 7, 1997
    Assignee: SGS-Thomson Microelectronics GmbH
    Inventors: Rainer Bonitz, Peter Birkenseher
  • Patent number: 5590075
    Abstract: A method for testing an electrically erasable and programmable memory device comprising a matrix of memory cells and redundancy memory cells for functionally substituting defective memory cells, comprises the steps of: programing all the memory cells of the memory device; submitting all the memory cells of the memory device to a preliminary electrical erasure for a time much shorter than an average erasing time of the memory cells; reading the information stored in all the memory cells of the memory device; memorizing the addresses of defective memory cells which have been read as erased memory cell; storing the addresses of the defective memory cells in redundancy registers associated to redundancy memory cells which must substitute the defective memory cells.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: December 31, 1996
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventor: Stefano Mazzali
  • Patent number: 5583820
    Abstract: A circuit for detecting a reduction below a threshold value in a supply voltage provided to storage devices integrated into a semiconductor. A comparator is coupled between a voltage supply line and a signal ground and has a first or reference input and a second or test-signal input. A generator of a stable voltage reference has an output coupled to the first input and a divider of the supply voltage coupled to the second input of the comparator. A circuit means is arranged to feed the voltage supply line with the higher of the supply voltage and a programming voltage also provided to the storage devices.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: December 10, 1996
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Silvia Padoan, Marco Olivo, Carla Golla
  • Patent number: 5572156
    Abstract: A control circuit for a power transistor, connected between two supply terminals in series with a load. The control circuit comprises a control logic circuit which produces a signal at two levels with respect to a reference terminal, a level shifter connected between the control circuit and the power transistor, which produces a signal at two levels relative to the node between the power transistor and the load. The level shifter comprises a flip-flop the output of which controls the power transistor, and an electronic switch, for example a MOSFET transistor, connected between the "set" input of the flip-flop and the node and controlled by the "reset" input of the flip-flop in such a way as to be closed when the "reset" input is greater, by a predetermined value, than that of the node. The electronic switch prevents the parasitic current flowing through the set and reset inputs from erroneously switching the power transistor.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: November 5, 1996
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Claudio Diazzi, Fabrizio Martignoni, Mario Tarantola
  • Patent number: 5561594
    Abstract: An electrical assembly comprises an electrical component having an array of contact bumps. The component is mounted on a multilayer printed circuit board having a plurality of conducting pins located in holes in the board and having pointed ends projecting above the board and making electrical contact with the bumps on the component.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: October 1, 1996
    Assignee: SGS-Thomson Microelectronics Ltd.
    Inventor: Elwyn P. M. Wakefield