Patents by Inventor Stephane Razafimandimby

Stephane Razafimandimby 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: 8493155
    Abstract: A controlled oscillator includes, connected in parallel, a capacitor configured to be tuneable based upon a first signal, an inductor, and an active impedance. The active impedance is formed by a pair of cross-coupled transistors connected so as to produce a negative resistive component at the terminals of the active impedance. Circuitry produces a degeneracy tuneable by a second signal in the cross-coupled pair, such that the cross-coupled pair produces a capacitive component tuneable based upon the second signal at the terminals of the active impedance.
    Type: Grant
    Filed: July 6, 2011
    Date of Patent: July 23, 2013
    Assignee: STMicroelectronics SA
    Inventor: Stephane Razafimandimby
  • Publication number: 20120007686
    Abstract: A controlled oscillator includes, connected in parallel, a capacitor configured to be tuneable based upon a first signal, an inductor, and an active impedance. The active impedance is formed by a pair of cross-coupled transistors connected so as to produce a negative resistive component at the terminals of the active impedance. Circuitry produces a degeneracy tuneable by a second signal in the cross-coupled pair, such that the cross-coupled pair produces a capacitive component tuneable based upon the second signal at the terminals of the active impedance.
    Type: Application
    Filed: July 6, 2011
    Publication date: January 12, 2012
    Applicants: STMicroelectronics SA
    Inventor: Stephane RAZAFIMANDIMBY
  • Patent number: 7920036
    Abstract: A lattice tunable filtering circuit includes a first input and a second input, and a first output and a second output. The circuit includes two series branches and two parallel branches. The first and second series branches include a Tunable Resonator Component (TRC) which presents a first series resonance frequency whereas the third and fourth parallel branches present a second series resonance frequency which has a value being lower than that of the first series resonance frequency. The first and second series resonance frequencies are tunable by one analog control quantity. The filtering circuit further includes a feedback control loop for the control of the analog quantity, which feedback is based on a criterion of equality between the modulus of impedances Zs and Zp.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: April 5, 2011
    Assignees: STMicroelectronics S.A., Centre National de la Recherche Scientifique
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Andreas Kaiser
  • Patent number: 7852174
    Abstract: A negative capacitances circuit includes first and second branches connected between a first reference voltage and a second reference voltage. The first branch includes, in series, a first biasing resistor, a first diode, a first bipolar transistor, and a first current source. The second branch includes, in series, a second biasing resistor, a second diode, a second bipolar transistor, and a second current source. The first transistor has a base coupled to a collector of the second transistor and to one input, and the second transistor has a base coupled to a collector of the first transistor and to another input. A capacitor is connected between the emitter of said first transistor and the emitter of said second transistor. A linearization resistor is coupled in parallel between the two emitters of said first and said second transistors.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: December 14, 2010
    Assignee: STMicroelectronics SA
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Cyrille Tilhac
  • Patent number: 7696844
    Abstract: A filtering circuit based on a lattice structure comprising a first and a second input and a first and second output. The circuit further comprises two series impedance and two parallel impedance which each comprises an acoustic resonator associated with two inductive and capacitive components which can be adjusted by a first control value. The second and fourth impedance comprise each an acoustic resonator associated to two inductive and capacitive components which are adjustable by means of a second control value. A control circuit generates the two control values which simultaneously comprise a common mode potential and a differential mode potential which allows the emergence of first and second pass bands which are usable for realizing two different bandpass filters.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: April 13, 2010
    Assignee: STMicroelectronics SA
    Inventors: Andreia Cathelin, Stéphane Razafimandimby, Andreas Kaiser
  • Patent number: 7683742
    Abstract: An electronic circuit includes: an acoustic resonator of BAW or SAW type, said resonator having a series resonance frequency and a parallel resonance frequency; an active circuit which is coupled in parallel to said acoustic resonator, said active circuit having a negative capacity acting on the parallel resonance frequency of said resonator.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: March 23, 2010
    Assignee: STMicroelectronics SA
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Cyrille Tilhac
  • Publication number: 20090072925
    Abstract: A lattice tunable filtering circuit includes a first input and a second input, and a first output and a second output. The circuit includes two series branches and two parallel branches. The first and second series branches include a Tunable Resonator Component (TRC) which presents a first series resonance frequency whereas the third and fourth parallel branches present a second series resonance frequency which has a value being lower than that of the first series resonance frequency. The first and second series resonance frequencies are tunable by one analog control quantity. The filtering circuit further includes a feedback control loop for the control of the analog quantity, which feedback is based on a criterion of equality between the modulus of impedances Zs and Zp.
    Type: Application
    Filed: September 2, 2008
    Publication date: March 19, 2009
    Applicant: STMICROELECTRONICS SA
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Andreas Kaiser
  • Patent number: 7423502
    Abstract: An electronic circuit comprises a resonator meant to be integrated into a semiconductor product including a resonator having first and second resonant frequencies. The electronic circuit comprises: a first inductive partner element for canceling out said second resonant frequency, said partner element having a quality coefficient QI (f) having a first value in a predetermined frequency band and a second value outside said frequency band; a second capacitive partner element for adjusting tuning of said resonator to said first frequency.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: September 9, 2008
    Assignee: STMicroelectronics SA
    Inventors: Stephane Razafimandimby, Didier Belot, Jean-François Carpentier, Andreia Cathelin
  • Publication number: 20080088393
    Abstract: An electronic circuit includes: an acoustic resonator of BAW or SAW type, said resonator having a series resonance frequency and a parallel resonance frequency; an active circuit which is coupled in parallel to said acoustic resonator, said active circuit having a negative capacity acting on the parallel resonance frequency of said resonator.
    Type: Application
    Filed: August 16, 2007
    Publication date: April 17, 2008
    Applicant: STMICROELECTRONICS S.A.
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Cyrille Tilhac
  • Publication number: 20080088390
    Abstract: A negative capacity circuit comprising: a first branch connected between a first reference voltage and a second voltage reference, said first branch comprising, in series, a first biasing resistor, a first diode, a collector-emitter junction of a first bipolar transistor and a first current source; a second branch connected between said first reference voltage (Vdd) and said second reference voltage, said second branch comprising, in series, a second biasing resistor, a second diode, a collector-emitter junction of a second bipolar transistor and a second current source, said first transistor having a base terminal which is coupled to the collector terminal of said second transistor and to one input, and said second transistor having a base terminal which is coupled to the collector terminal of said first transistor and to another input; a capacitor connected between the emitter terminal of said first bipolar transistor and the emitter terminal of said second bipolar transistor; a linearization resistor which
    Type: Application
    Filed: August 16, 2007
    Publication date: April 17, 2008
    Applicant: STMICROELECTRONICS S.A.
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Cyrille Tilhac
  • Patent number: 7218181
    Abstract: An amplitude-locked loop (ALL) includes: a comparator circuit having a first input, a second input and an output, said first input receiving an electric reference signal; a loop filter having an input connected to said output of said comparator circuit and having an output generating an electric control signal (Vtune); a circuit generating an electric signal to be controlled, transmitted to said second input of said comparator circuit. The circuit comprises an acoustic resonator having a BAW-type resonator having a first and second resonant frequencies and associated with a first inductive partner element for removing said second resonant frequency and with a second capacitive partner element for tuning said first resonant frequency, said at least first resonator component being adjustable via said electric control signal (Vtune).
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: May 15, 2007
    Assignee: STMicroelectronics S.A.
    Inventors: Stephane Razafimandimby, Andreia Cathelin
  • Patent number: 7187240
    Abstract: An integrated electronic circuit comprises at least first and second variable resonator elements that can be tuned by means of an electric signal (Vtune) and that are arranged on the same silicon substrate, and that are respectively integrated into a Master circuit and a Slave circuit. Each resonator element is associated with a first inductive partner element set in the vicinity of the resonant and antiresonant frequencies; and with a second capacitive partner element, at least one of said partner elements being adjustable by means of said electric signal (Vtune). Controlling both partner elements could be done either by means of an adjustable capacitor, as a varactor, or by means of an inductor, passive or active, fixed or variable.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: March 6, 2007
    Assignee: STMicroelectronics S.A.
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Didier Belot, Jean-François Carpentier
  • Publication number: 20050189999
    Abstract: An integrated electronic circuit comprises at least first and second variable resonator elements that can be tuned by means of an electric signal (Vtune) and that are arranged on the same silicon substrate, and that are respectively integrated into a Master circuit and a Slave circuit. Each resonator element is associated with a first inductive partner element set in the vicinity of the resonant and antiresonant frequencies; and with a second capacitive partner element, at least one of said partner elements being adjustable by means of said electric signal (Vtune). Controlling both partner elements could be done either by means of an adjustable capacitor, as a varactor, or by means of an inductor, passive or active, fixed or variable.
    Type: Application
    Filed: December 29, 2004
    Publication date: September 1, 2005
    Applicant: STMicroelectronics S.A.
    Inventors: Andreia Cathelin, Stephane Razafimandimby, Didier Belot, Jean-Francois Carpentier
  • Publication number: 20050189997
    Abstract: An amplitude-locked loop (ALL) includes: a comparator circuit having a first input, a second input and an output, said first input receiving an electric reference signal; a loop filter having an input connected to said output of said comparator circuit and having an output generating an electric control signal (Vtune); a circuit generating an electric signal to be controlled, transmitted to said second input of said comparator circuit. The circuit comprises an acoustic resonator having a BAW-type resonator having a first and second resonant frequencies and associated with a first inductive partner element for removing said second resonant frequency and with a second capacitive partner element for tuning said first resonant frequency, said at least first resonator component being adjustable via said electric control signal (Vtune).
    Type: Application
    Filed: December 29, 2004
    Publication date: September 1, 2005
    Applicant: STMicroelectronics S.A.
    Inventors: Stephane Razafimandimby, Andreia Cathelin
  • Publication number: 20050174198
    Abstract: An electronic circuit comprises a resonator meant to be integrated into a semiconductor product including a resonator having first and second resonant frequencies. The electronic circuit comprises: a first inductive partner element for canceling out said second resonant frequency, said partner element having a quality coefficient QI (f) having a first value in a predetermined frequency band and a second value outside said frequency band; a second capacitive partner element for adjusting tuning of said resonator to said first frequency.
    Type: Application
    Filed: December 29, 2004
    Publication date: August 11, 2005
    Applicant: STMicroelectronics S.A.
    Inventors: Stephane Razafimandimby, Didier Belot, Jean-Francois Carpentier, Andreia Cathelin