Patents by Inventor Claudio Tavazzani

Claudio Tavazzani 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).

  • Patent number: 6344774
    Abstract: An integrated power operational amplifier can alternatively be operated in a master or a slave mode, such that a master amplifier can be connected in parallel with one or more slave amplifiers. This arrangement allows very low impedance loads to be driven, as well as allowing the heat dissipation to be distributed over a number of operational amplifiers, thereby raising the maximum dissipation limits of integrated power systems. In addition, by eliminating the ballast resistors, more power can be delivered by the system, for the same supply voltage, and less power is dissipated.
    Type: Grant
    Filed: June 25, 2001
    Date of Patent: February 5, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Giorgio Ghiozzi, Claudio Tavazzani
  • Patent number: 6342811
    Abstract: An integrated power operational amplifier can alternatively be operated in a master or a slave mode, such that a master amplifier can be connected in parallel with one or more slave amplifiers. This arrangement allows very low impedance loads to be driven, as well as allowing the heat dissipation to be distributed over a number of operational amplifiers, thereby raising the maximum dissipation limits of integrated power systems. In addition, by eliminating the ballast resistors, more power can be delivered by the system, for the same supply voltage, and less power is dissipated.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: January 29, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventors: Giorgio Ghiozzi, Claudio Tavazzani
  • Patent number: 6320465
    Abstract: A constant limit duty-cycle is established by detecting the equivalent values VDD′ and −VDD″ of the voltages to which the output signal of the amplifier switches or pseudo supplies. An input limiting stage receiving an analog input signal utilizes the pseudo supply values VDD′ and −VDD″ as respective reference values for limiting the voltage swing of the analog signal output to a pre-defined fraction &agr;<1 of such reference values. This avoids using as a reference the real supply voltage values VDD and −VDD, as commonly done. The constant limit duty cycle is substantially independent from fabrication process spreads, temperature, etc., and provides an optimal functioning of the final stage of the amplifier for all working conditions.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: November 20, 2001
    Assignee: STMicroelectronics S.r.l.
    Inventors: Marco Masini, Claudio Tavazzani
  • Publication number: 20010035790
    Abstract: An integrated power operational amplifier can alternatively be operated in a master or a slave mode, such that a master amplifier can be connected in parallel with one or more slave amplifiers. This arrangement allows very low impedance loads to be driven, as well as allowing the heat dissipation to be distributed over a number of operational amplifiers, thereby raising the maximum dissipation limits of integrated power systems. In addition, by eliminating the ballast resistors, more power can be delivered by the system, for the same supply voltage, and less power is dissipated.
    Type: Application
    Filed: June 25, 2001
    Publication date: November 1, 2001
    Inventors: Giorgio Ghiozzi, Claudio Tavazzani
  • Publication number: 20010022531
    Abstract: An integrated power operational amplifier can alternatively be operated in a master or a slave mode, such that a master amplifier can be connected in parallel with one or more slave amplifiers. This arrangement allows very low impedance loads to be driven, as well as allowing the heat dissipation to be distributed over a number of operational amplifiers, thereby raising the maximum dissipation limits of integrated power systems. In addition, by eliminating the ballast resistors, more power can be delivered by the system, for the same supply voltage, and less power is dissipated.
    Type: Application
    Filed: May 25, 2001
    Publication date: September 20, 2001
    Inventors: Giorgio Ghiozzi, Claudio Tavazzani
  • Patent number: 6262627
    Abstract: An integrated power operational amplifier can alternatively be operated in a master or a slave mode, such that a master amplifier can be connected in parallel with one or more slave amplifiers. This arrangement allows very low impedance loads to be driven, as well as allowing the heat dissipation to be distributed over a number of operational amplifiers, thereby raising the maximum dissipation limits of integrated power systems. In addition by eliminating the ballast resistors, more power can be delivered by the system, for the same supply voltage, and less power is dissipated.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: July 17, 2001
    Assignee: STMicroelectronics S.r.l.
    Inventors: Giorgio Ghiozzi, Claudio Tavazzani
  • Patent number: 5952881
    Abstract: A power stage for an operational amplifier includes an output stage, a current source stage, and a gain stage. The output stage is formed by first and second NPN output transistors arranged in a Totem-Pole configuration, each having respective resistors connected between their respective base and emitter terminals. The output transistors are biased in class AB by a quiescent current supplied by the current source stage and are controlled dynamically by the gain stage. The gain stage includes an NPN gain transistor having a collector terminal connected to the base terminal of the first output transistor and an emitter terminal connected to the base terminal of the second output transistor.
    Type: Grant
    Filed: April 24, 1997
    Date of Patent: September 14, 1999
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Giorgio Chiozzi, Sandro Storti, Claudio Tavazzani
  • Patent number: 5798672
    Abstract: An amplifier is formed by an astable multivibrator having a signal output supplying a two-state output signal to a power stage, that presents an output voltage (V.sub.o) switching between a first and second value. The output voltage presents a duty cycle varying with the input signal (V.sub.in) of the multivibrator. The amplifier, when connected between first and second supply lines that are symmetrical with respect to ground and are subject to supply noise, comprises a current source for generating the bias current of the astable multivibrator and supplying a current (I) that is switchable at each half cycle. The value of the current at each half cycle is proportional to the absolute value of the output voltage (V.sub.o) of the amplifier to vary the duty cycle of the amplifier in a manner correlated the supply noise, so that the average output voltage value is zero.
    Type: Grant
    Filed: July 9, 1996
    Date of Patent: August 25, 1998
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Marco Masini, Claudio Tavazzani, Stefania Boiocchi
  • Patent number: 5568342
    Abstract: Circuit for protection of an amplifier stage comprising circuit switching means for turn-off of the stage and piloted through a logic gate OR by a monostable, which generates upon arise of abnormal operating conditions turn-off command signals having a predetermined duration.A sensing circuit upon persistence of abnormal conditions at start-up or during normal operation also sends turn-off signals through the logic gate OR after enablement through a gate AND.The signals of any enablement at the logic gate AND arrive through a logic gate OR from a window comparator coupled with stage start-up members, from the monostable, and from the output of said logic gate AND as a confirmation signal.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: October 22, 1996
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Claudio Tavazzani, Andrea Fassina, Fabrizio Stefani
  • Patent number: 5315268
    Abstract: An amplifier comprising a power stage the output of which is compared with a reference level by a comparator. If the output exceeds the reference level, a reduction is made in the gain of a variable-gain cell upstream from the power stage. The reference level varies with temperature, and, more specifically, presents a high constant value (e.g., greater than the supply voltage) when temperature is below a predetermined threshold (e.g., 130.degree. C.), and decreases in proportion to an increase in temperature, when the temperature exceeds the predetermined threshold. Thus, the input signal is only attenuated in the event the output signal exceeds given values inversely proportional to temperature, and with no reduction in peak output at high temperature.
    Type: Grant
    Filed: October 15, 1992
    Date of Patent: May 24, 1994
    Assignee: SGS-Thomson Microelectronics s.r.l.
    Inventors: Edoardo Botti, Claudio Tavazzani