Automatic Patents (Class 331/183)
  • Patent number: 9763726
    Abstract: A system is provided. The system includes an electrosurgical generator configured to measure, collect and record data pertaining to a characteristic of tissue as the tissue is being electrosurgically treated. A tuner configured to couple to the electrosurgical generator includes a tuning circuit providing a load having a variable complex impedance for the electrosurgical generator when the electrosurgical generator is connected thereto. A controller including stored data pertaining to impedance values is in operable communication with the electrosurgical generator for retrieving the recorded data pertaining to the characteristic of tissue. The controller is in operable communication with the tuner for varying a complex impedance of the load. The controller configured to compare the recorded data pertaining to the at least one characteristic of tissue with the stored data pertaining to the plurality of impedance values and to adjust the tuner to one of the plurality of impedance values.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: September 19, 2017
    Assignee: COVIDIEN LP
    Inventors: Robert J. Behnke, II, Peter L. Valentyik, Scott E. M. Frushour
  • Patent number: 9531389
    Abstract: Adjusting a voltage-controlled oscillator (VCO) accurately and reliably. The voltage-controlled oscillator VCO attempts to generate an output signal with a programmed known frequency. An ALC circuit and a VCTA circuit adjust the VCO's amplitude and frequency. The system alternates making changes between amplitude or frequency, checking at each change what (difficult-to-predict) effect this has had on the output of the VCO. Each time the VCO switched capacitor array setting is changed, a circuit reviews the VCO output, and determines whether the VCO output should be adjusted in amplitude and frequency. The VCO amplitude and the VCO frequency are adjusted in alternating steps, that is, adjusting the VCO frequency, determining if further adjustments are desired, adjusting the VCO amplitude, determining if further adjustments are desired, and repeating until the VCO coarse adjustment has been sufficiently conducted.
    Type: Grant
    Filed: September 15, 2014
    Date of Patent: December 27, 2016
    Inventor: Farbod Behbahani
  • Patent number: 9225341
    Abstract: The present invention provides an automatic amplitude control circuit, including an oscillator, a collecting module, a first analog current generating module, a second analog current generating module, and a numerical control current generating module. According to this automatic amplitude control circuit, a low-noise numerical control bias current can be provided for the oscillator.
    Type: Grant
    Filed: September 23, 2014
    Date of Patent: December 29, 2015
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Qing Min, Jiale Huang, Nianyong Zhu
  • Patent number: 9112448
    Abstract: An oscillator circuit may selectively switch between a normal mode and a low-power mode in response to a mode signal. During the normal mode, the oscillator circuit may employ a first amplifier configuration and a first capacitive loading to generate a high-accuracy clock signal having a relatively low frequency error. During the low power mode, the oscillator circuit may employ a second amplifier configuration and a second capacitive loading to generate a low-power clock signal using minimal power consumption. A compensation circuit may be used to offset a relatively high frequency error during the low-power mode.
    Type: Grant
    Filed: October 28, 2013
    Date of Patent: August 18, 2015
    Assignee: QUALCOMM Incorporated
    Inventor: Emmanouil Terrovitis
  • Patent number: 9008601
    Abstract: A circuit for a single differential-inductor oscillator with common-mode resonance may include a tank circuit formed by coupling a first inductor with a pair of first capacitors; a cross-coupled transistor pair coupled to the tank circuit; and one or more second capacitors coupled to the tank circuit and the cross-coupled transistors. The single differential-inductor oscillator may be configured such that a common mode (CM) resonance frequency (FCM) associated with the single differential-inductor oscillator is at twice a differential resonance frequency (FD) associated with the single differential-inductor oscillator.
    Type: Grant
    Filed: August 16, 2013
    Date of Patent: April 14, 2015
    Assignee: Broadcom Corporation
    Inventors: David Patrick Murphy, Hooman Darabi
  • Patent number: 8988156
    Abstract: An oscillator/amplifier has a gain controlled amplifier that maintains a desired oscillation waveform amplitude for all possible oscillation frequencies of operation. A peak detector produces a direct current (DC) voltage proportional to the oscillation waveform, and a voltage reference generator provides a reference voltage that is compared against the DC voltage from the peak detector. When the DC voltage is less than the reference voltage the gain of the amplifier is increased, and when the DC voltage is equal to or greater than the reference voltage the gain of the amplifier is decreased. A programmable voltage reference generator may also be used to provide for selection of different oscillation waveform amplitudes. A digital control loop controls the oscillation waveform amplitude over the entire possible frequency range of operation. Various frequency determining elements, e.g., crystal, piezoelectric resonator, inductor-capacitor tuned circuit, resistor-capacitor network, etc.
    Type: Grant
    Filed: May 14, 2013
    Date of Patent: March 24, 2015
    Assignee: Microchip Technology Incorporated
    Inventor: Rohit Vaishnav
  • Patent number: 8988159
    Abstract: There is provided an oscillator capable of lowering the power supply voltage without degrading the phase noise, while employing the conventional circuit configuration. According to one aspect of the present invention, there is provided an oscillator comprising: an oscillation circuit; a bias generation circuit for generating a bias signal to drive the oscillation circuit; and a booster circuit for boosting a power supply voltage to generate a boosted voltage for driving the bias generation circuit. In addition, the oscillation circuit, the bias generation circuit, and the booster circuit are provided in a single IC chip, and the booster circuit may receive the power supply voltage VDD from the power supply arranged at the exterior of the IC chip.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: March 24, 2015
    Assignee: Asahi Kasei Microdevices Corporation
    Inventor: Haruhiko Maru
  • Patent number: 8975976
    Abstract: A power management apparatus and method for maintaining a substantially constant duty cycle of a reference clock signal in a multi-power oscillator, includes a first output power transistor in electrical parallel with a series arrangement of a second output power transistor and a switch, and a crystal oscillator capacitively coupled to a common gate of the first and second output power transistors, wherein a level of the reference clock signal power output is a normal power level when the switch is open and the level of the reference clock signal power output is a higher power level when the switch is closed to operate the second output power transistor in parallel with the first output power transistor.
    Type: Grant
    Filed: March 6, 2013
    Date of Patent: March 10, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Jingyu Hu, Michael Naone Farias
  • Patent number: 8963650
    Abstract: A semiconductor device contrived to prevent a reference voltage and a reference current which are supplied to a high speed OCO from varying with a change in ambient temperature and/or a change in an external power supply voltage and to reduce the circuit area of a power supply module. The high speed OCO outputs a high speed clock whose magnitude is determined by the reference current and the reference voltage. A logic unit adjusts the values of the reference current and reference voltage, according to the reference voltage and reference current trimming codes related to detected ambient temperature and operating voltage.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: February 24, 2015
    Assignee: Renesas Electronics Corporation
    Inventors: Tsukasa Oishi, Katsuyoshi Mitsui, Naoki Otani
  • Patent number: 8957740
    Abstract: Representative implementations of devices and techniques provide increased negative resistance to an oscillator circuit. A capacitance divider and/or a feedback loop may be employed to increase the negative resistance of the oscillator circuit at the same current consumption and with the same load capacitance. Further, a constant bias circuit may be employed to conserve and/or reduce the current consumption of the oscillator circuit.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: February 17, 2015
    Assignee: Intel Mobile Communications GmbH
    Inventors: David Gaied, Emad Hegazi, Karim Hussein
  • Patent number: 8952762
    Abstract: A clock generator includes, in part, a buffer, a peak detector and a control logic. The buffer generates a clock output signal in response to receiving a clock signal and a feedback signal that controls the gain of the buffer. If the peak detector detects that the amplitude of the output signal is higher than the upper bound of the predefined range, the gain value applied to the variable buffer is decreased. If the peak detector detects that the amplitude of the output signal is lower than the lower bound of the predefined range, the gain value applied to the variable buffer to increased. If the peak detector detects that the amplitude of the output signal is within the predefined range, no change is made to the gain value applied to the variable buffer. The control logic generates the feedback signal in response to the peak detector's output signal.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: February 10, 2015
    Assignee: MaxLinear, Inc.
    Inventor: Tomas O'Sullivan
  • Patent number: 8922285
    Abstract: The invention relates to a radiofrequency oscillator which incorporates: a spin-polarized electric current magnetoresistive device (6), a terminal (18) for controlling the frequency or amplitude of the oscillating signal, a servo loop (34) connected between the output terminal and the control terminal for applying a control signal to the control terminal in order to slave a characteristic of the oscillating signal to a reference value, the servo loop (34) comprising: a sensor (36) of the amplitude of the oscillating signal oscillations, and a comparator (38) capable of generating the control signal according to the measured amplitude and the reference value.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: December 30, 2014
    Assignees: Commissariat à l'énergie atomique et aux énergies alternatives, Centre National de la Recherche Scientifique
    Inventors: Dimitri Houssameddine, Bertrand Delaet, Marie-Claire Cyrille, Ursula Ebels, Michael Quinsat
  • Patent number: 8922287
    Abstract: Systems and methods for amplitude loop control for oscillators. In some embodiments, an electronic circuit may include oscillator circuitry configured to produce a periodic signal, and control circuitry operably coupled to the oscillator circuitry, the control circuitry including switched capacitor circuitry configured to determine a difference between maximum and minimum peak voltage values of the periodic signal, the control circuit configured to control a voltage amplitude of the periodic signal based upon the difference. In other embodiments, a method may include receiving a clock signal from a clock generator, determining, using a switched capacitor circuit, a first peak voltage value of the clock signal, determining, using the switched capacitor circuit, a second peak voltage value of the clock signal, and controlling a bias current applied to the clock generator based upon a difference between the first and second peak voltage values.
    Type: Grant
    Filed: January 30, 2013
    Date of Patent: December 30, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Andre Luis Vilas Boas, Alfredo Olmos, Eduardo Ribeiro da Silva, Ricardo Maltione
  • Patent number: 8902011
    Abstract: A signal generating circuit for a real time clock device is disclosed, having an oscillating circuit, a voltage detecting circuit, and a control circuit. The oscillating circuit is used for generating oscillating signals. The voltage detecting circuit is used for detecting a voltage level coupled with the signal generating circuit. The control circuit is coupled with the oscillating circuit and the voltage detecting circuit. When the voltage level detected by the voltage detecting circuit locates in a predetermined range, the control circuit configures the oscillating circuit to generate the oscillating signals with a larger current at a first interval and to generate the oscillating signals with a smaller current at a second interval. The control circuit further generates a clock signal according to the oscillating signals at a third interval.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: December 2, 2014
    Assignee: Alchip Technologies, Ltd.
    Inventors: Wen-Hong Su, Zen-Chuan Lin
  • Patent number: 8896390
    Abstract: A circuit of inductance/capacitance (LC) voltage control oscillator (VCO) includes an LC VCO unit, a peak detector and a processing unit. The LC VCO unit receives a current control signal and outputs an oscillating voltage signal. The peak detector receives the oscillating voltage signal to obtain an averaged voltage value. The processing unit receives the averaged voltage value to accordingly output the current control signal and feedback to the LC VCO unit. The processing unit also detects whether or not the averaged voltage value has reached to a saturation state and a corresponding critical current. After the current control signal reaches to the critical current, the current control signal is set within a variance range near the critical current.
    Type: Grant
    Filed: June 13, 2012
    Date of Patent: November 25, 2014
    Assignee: Novatek Microelectronics Corp.
    Inventor: Chih-Hung Chen
  • Patent number: 8884718
    Abstract: A substantially temperature-independent LC-based oscillator uses bias control techniques. Temperature independence may be achieved by controlling the harmonic frequency content of the output of the oscillator by controlling the amplitude. Amplitude control may be achieved by inserting a control mechanism in the feedback loop of the oscillator.
    Type: Grant
    Filed: August 8, 2012
    Date of Patent: November 11, 2014
    Assignee: Si-Ware Systems
    Inventors: Nabil M. Sinoussi, Mohamed M. Weheiba, Ahmed A. Helmy, Ahmed H. A. Razek, Ayman Ahmed
  • Patent number: 8884711
    Abstract: A MEMS device and method for amplitude regulation of a MEMS device are disclosed. In a first aspect, the MEMS device comprises a MEMS resonator, a limiter coupled to the MEMS resonator, and a regulator coupled to the limiter. The MEMS device includes an amplitude control circuit coupled to the MEMS resonator. The amplitude control circuit controls a supply of the limiter via the regulator to regulate oscillation loop amplitude of the MEMS device. In a second aspect, the method includes coupling a regulator to the limiter, coupling an amplitude control circuit to the MEMS resonator, and controlling a supply of the limiter via the regulator to regulate oscillation loop amplitude of the MEMS device.
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: November 11, 2014
    Assignee: InvenSense, Inc.
    Inventor: Vadim Tsinker
  • Patent number: 8884709
    Abstract: A phase-locked loop double-point modulator may include a frequency divider having a ratio which can be changed by a first modulation signal, and an oscillator, a frequency of which can be changed by a second modulation signal correlated to the first modulation signal. A calibration circuit may be configured, in a calibration mode, to match the gains of the first and second modulation signals based on frequency measurements of the oscillator for two different calibration values of the second modulation signal. The phase-locked double-point modulator may also include an attenuator having a constant ratio greater than 1 and placed in the path of the second modulation signal, and a selector switch configured to be controlled by the calibration circuit to reduce the ratio of the attenuator in the calibration mode.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: November 11, 2014
    Assignee: STMicroelectronics (Grenoble 2) SAS
    Inventors: Franck Badets, Serge Ramet, Michel Ayraud
  • Publication number: 20140266487
    Abstract: An oscillator/amplifier has a gain controlled amplifier that maintains a desired oscillation waveform amplitude for all possible oscillation frequencies of operation. A peak detector produces a direct current (DC) voltage proportional to the oscillation waveform, and a voltage reference generator provides a reference voltage that is compared against the DC voltage from the peak detector. When the DC voltage is less than the reference voltage the gain of the amplifier is increased, and when the DC voltage is equal to or greater than the reference voltage the gain of the amplifier is decreased. A programmable voltage reference generator may also be used to provide for selection of different oscillation waveform amplitudes. A digital control loop controls the oscillation waveform amplitude over the entire possible frequency range of operation. Various frequency determining elements, e.g., crystal, piezoelectric resonator, inductor-capacitor tuned circuit, resistor-capacitor network, etc.
    Type: Application
    Filed: May 14, 2013
    Publication date: September 18, 2014
    Applicant: Microchip Technology Incorporated
    Inventor: Rohit Vaishnav
  • Patent number: 8836444
    Abstract: An illustrative system includes an amplifier operably connected to a phase shifter. The amplifier is configured to amplify a voltage from an oscillator. The phase shifter is operably connected to a driving amplitude control, wherein the phase shifter is configured to phase shift the amplified voltage and is configured to set an amplitude of the phase shifted voltage. The oscillator is operably connected to the driving amplitude control. The phase shifted voltage drives the oscillator. The oscillator is at an internal resonance condition, based at least on the amplitude of the phase shifted voltage, that stabilizes frequency oscillations in the oscillator.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: September 16, 2014
    Assignee: Uchicago Argonne, LLC
    Inventors: Omar Daniel Lopez, Dario Antonio
  • Patent number: 8836434
    Abstract: A digital frequency synthesizer with an automatic calibration system. The digital frequency synthesizer is calibrated by initiating a coarse tuning operation to rapidly reach a preliminary frequency that is proximate to the desired final frequency. A calibration procedure is then executed for adjusting gain in the frequency synthesizer based on the preliminary frequency. This test involves applying one or more test signals to the frequency synthesizer and measuring a signal generated in the frequency synthesizer. This measured signal corresponds to a gain response of the circuit at the preliminary frequency. When the expected gain is known, any difference relative to the gain of the measured signal is used to adjust the gain in a circuit of the frequency synthesizer such that the actual gain substantially matches the expected gain.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: September 16, 2014
    Assignee: Icera Inc.
    Inventors: Abdellatif Bellaouar, Ahmed R. Fridi, Sher Jiun Fang, Hamid Safiri
  • Patent number: 8823460
    Abstract: The invention relates to a radiofrequency oscillator which incorporates: a spin-polarized electric current magnetoresistive device (6) for generating an oscillating signal at an oscillation frequency on an output terminal (10), and a terminal (18) for controlling the frequency or amplitude of the oscillating signal, and a feedback loop (44) comprising an amplifier (46) provided with: an input connected to the output terminal (10) of the magnetoresistive device (6) so as to amplify the portion of an oscillating signal detected at the output terminal, and an output connected to the control terminal (18) so as to inject onto said control terminal the amplified portion of the oscillating signal which is phase-related to the oscillating signal generated at the output terminal.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: September 2, 2014
    Assignee: Commissariat a l'energie atomique et aux energies alternatives
    Inventors: Dimitri Houssameddine, Bertrand Delaet, Marie-Claire Cyrille, Ursula Ebels, Michael Quinsat
  • Patent number: 8816786
    Abstract: A large gain is used to start up the oscillation of the crystal quickly. Once the oscillation starts, the amplitude is detected. A control circuit determines based on the measured amplitude to disable a low resistance path in the controlled switch array to reduce the applied gain below the power dissipation specification of the crystal. Another technique introduces a mixed-signal controlled power supply multi-path resistive array which tailors the maximum current to the crystal. A successive approximation register converts the amplitude into several partitions and enables/disables one of several power routing paths to the inverter of the oscillator. This allows a better match between the crystal selected by the customer and the on-chip drive circuitry to power up the oscillator without stressing the crystal. The “l/f” noise of the oscillator circuit is minimized by operating transistors in the triode region instead of the linear region.
    Type: Grant
    Filed: October 1, 2012
    Date of Patent: August 26, 2014
    Assignee: Tensorcom, Inc.
    Inventor: KhongMeng Tham
  • Patent number: 8810323
    Abstract: In one embodiment, a voltage-controlled oscillator (VCO) is provided that includes: a plurality of differential inverters coupled to form a loop, each differential inverter having a differential pair of transistors configured to steer a tail current from a current source, the current source sourcing the tail current responsive to a bias voltage, wherein each transistor in the differential pair couples to a power source through a corresponding switching-capacitor circuit; and a bias circuit configured to generate the bias voltage such that a transconductance for each transistor in the differential pairs is proportional to a factor that is a function of a ratio of transistor widths within the bias circuit.
    Type: Grant
    Filed: January 26, 2012
    Date of Patent: August 19, 2014
    Inventor: Mohammad Ardehali
  • Patent number: 8810329
    Abstract: An LC oscillator tank that generates a tank oscillation at a phase substantially equal to a temperature null phase. The oscillator further includes frequency stabilizer circuitry coupled to the LC oscillator tank to cause the LC oscillator tank to operate at the temperature null phase. In one aspect of the disclosure, a feedback loop may split the output voltage of the LC tank into two voltages having different phases, where each voltage is independently transformed into a current through programmable transconductors, The two currents may be combined to form a resultant current which is then applied to the LC tank. The phase of the resultant current is such that the LC tank operates at an impedance condition that achieves frequency stability across temperature.
    Type: Grant
    Filed: August 8, 2012
    Date of Patent: August 19, 2014
    Inventors: Nabil M. Sinoussi, Bassel Hanafi
  • Patent number: 8803621
    Abstract: An oscillation circuit section is provided which can attain the reduction of a consumed power amount and the reduction of a manufacturing cost. In a semiconductor device, voltages are generated to drive the oscillation circuit section by using a plurality of MOS transistors which are connected in serial and each of which is in a diode connection. At this time, each voltage is generated based on a power supply voltage and a ratio of the threshold voltages of the plurality of MOS transistors. Therefore, it is possible to suppress the threshold voltage of each MOS transistor, to save an area of each MOS transistor, and to reduce the consumed power amount of the oscillation circuit section.
    Type: Grant
    Filed: September 15, 2012
    Date of Patent: August 12, 2014
    Assignee: Renesas Electronics Corporation
    Inventor: Sanae Suzuki
  • Patent number: 8729971
    Abstract: An oscillator includes a reference voltage generator, an oscillation element configured to oscillate by either a drive voltage or a drive current and output an oscillation signal, a peak hold element configured to detect a peak level of the oscillation signal for output; and a controller configured to increase or decrease the drive voltage or drive current in accordance with the reference voltage generated by the reference voltage generator and the peak level output from the peak hold element.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: May 20, 2014
    Assignee: Ricoh Company, Ltd.
    Inventor: Shinichi Kubota
  • Patent number: 8729974
    Abstract: A crystal oscillator circuit is configured to output an oscillation signal. A bias circuit responds to control signal to generate a bias current for application to the crystal oscillator circuit. A current generator generates a sense current from the control signal. The sense current is compared to a reference current by a comparator circuit. The comparator circuit generates a ready signal in response to the comparison. The ready signal is indicative of whether the oscillation signal output from the crystal oscillator circuit is ready for use by other circuitry. The reference current may be generated by a circuit which replicates the bias circuit.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: May 20, 2014
    Assignee: STMicroelectronics S.r.l.
    Inventors: Giulio Zoppi, Raffaele Iardino
  • Patent number: 8723610
    Abstract: A bias loop is used to program LC tank common mode voltage to allow operation at two different supply voltages VDD (e.g., 2.5V and 1.2V), and two different tank swings. This also allows lower phase noise through optimizing Ids shape allowing class C operation for both voltages. The two different supply voltages allow operation using multiple communication protocols such as 802.11n and 802.11ac within a common VCO circuit. The VCO can form part of a transceiver to provide frequencies in multiple bands.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: May 13, 2014
    Assignee: Broadcom Corporation
    Inventor: Zhiheng Cao
  • Patent number: 8710929
    Abstract: A system and method are provided for combined generation of I and Q signal references according to a periodic input signal and selective phase interpolation of an output signal with reference thereto. A ring oscillator portion generates an oscillator signal, and includes a plurality of delay stages interconnected in cascade to collectively execute an odd number of signal state inversions within a closed loop. The delay stages establish at respective nodes defined therebetween correspondingly delayed oscillator signal versions, successively shifted in phase by a predetermined phase difference. A signal injection portion selectively applies to at least one node of the ring oscillator portion a current bias according to the periodic input signal, and selectively adjusts each current bias in amplitude. The oscillator signal is thereby frequency locked to the periodic input signal, defining I/Q references with respect to the delayed oscillator signal version established at the current biased node.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: April 29, 2014
    Assignee: Cadence Design Systems, Inc.
    Inventors: Eric Naviasky, Chris Moscone, Rajagopal Vijayaraghavan, Benjamin Louis Heilmann
  • Patent number: 8710937
    Abstract: An apparatus includes a tank circuit of a voltage controlled oscillator. A pair of alternating current coupling capacitors respectively couple the gates of the pair of transistors to the drains of the pair of transistors. A bias circuit is coupled to the gates of the pair of transistors and biases the transistors in accordance with a bias voltage such that the transistors alternatingly turn on during a plurality of peaks of an oscillating signal of the tank circuit and the transistors turn off during a plurality of crossing points of the oscillating signal. A feedback loop may be configured to detect a peak oscillating amplitude of the oscillating signal and adjust a bias voltage of the bias circuit based on the peak oscillating amplitude. Also, a supply capacitor may be coupled to the tank circuit and to the transistors to provide an instantaneous current to the VCO.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: April 29, 2014
    Assignee: Marvell International Ltd.
    Inventor: Sehat Sutardja
  • Patent number: 8686798
    Abstract: An oscillator circuit generates a voltage signal. The magnitude of the voltage signal is measured and compared with predetermined upper and lower voltage signals by an internal test circuit. If the magnitude of the voltage signal is between the predetermined upper and lower voltage signals, then a pass test status signal is generated. If the magnitude of the voltage signal is not between the predetermined upper and lower voltage signals then a fail test status signal is generated.
    Type: Grant
    Filed: May 3, 2012
    Date of Patent: April 1, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jun Zhang, Xiuqiang Xu
  • Patent number: 8674779
    Abstract: One aspect of the present invention includes a reference current generator circuit. The circuit includes a bias circuit configured to generate a reference current along a first current path and a second current along a second current path. The reference current and the second current can be proportional. The circuit also includes a first pair of transistors connected in series and configured to conduct the reference current in the first current path. The circuit further includes a second pair of transistors connected in series and configured to conduct the second current in the second current path. The second pair of transistors can be coupled to the first pair of transistors to provide a collective resistance value of the second pair of transistors that is proportional to temperature.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: March 18, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Ming Xiao, Jian Wang, Jun Yi
  • Patent number: 8648662
    Abstract: An oscillator circuit for producing a frequency signal has a resonator element, an amplifier circuit and a coupling apparatus. The coupling apparatus connects the amplifier circuit to the resonator element for the duration of a switching-on process in the oscillator circuit.
    Type: Grant
    Filed: March 3, 2010
    Date of Patent: February 11, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Klaus Getta, Giuseppe Li Puma
  • Patent number: 8643445
    Abstract: Oscillator circuits are disclosed herein. An embodiment of an oscillator circuit includes a first bias circuit and a second bias circuit. An oscillator first connection terminal is coupled to a node, wherein the node is coupled to the first bias circuit and the second bias circuit. An oscillator second connection terminal connected to the second bias circuit. An increase in the oscillation amplitude of the oscillator increases the current in the second bias circuit and causes a reduction in the bias current in the first bias circuit.
    Type: Grant
    Filed: August 8, 2012
    Date of Patent: February 4, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Sreekiran Samala
  • Patent number: 8638173
    Abstract: A method of calibrating a phase-locked loop (PLL) while maintaining lock includes detecting that a control signal to an oscillator in a PLL has exceeded a threshold value while the PLL is locked to an input signal. In response, an operating current of the oscillator is adjusted to return the control signal below the threshold value while maintaining lock of the PLL to the input signal. Adjusting the operating current includes slowly varying an output current of a calibration circuit coupled to the PLL, enabling the PLL to maintain lock to the input signal during adjustment of the operating current.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: January 28, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Glenn A. Murphy, Xiaohua Kong, Nam V. Dang
  • Patent number: 8629730
    Abstract: Provided is a temperature compensated oscillator includes an oscillation circuit for oscillating an oscillator. In the oscillator, when an oscillation frequency is changed by a second control signal after being controlled by a first control signal, variation in the oscillation frequency due to a second control signal is set to a fixed amount. The oscillation frequency of the oscillator is controlled on the basis of both the first control signal and the second control signal, but an oscillation amplitude adjusting section is also added, the oscillation amplitude adjusting section allowing the oscillation amplitude of the oscillator to be changed by the second control signal. The oscillator thus allows a fixed amount of oscillation frequency control over a wide range (full range) of oscillation frequency control due to the first control signal.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: January 14, 2014
    Assignee: Asahi Kasei Microdevices Corporation
    Inventors: Kenji Nemoto, Tamami Furuya
  • Patent number: 8618889
    Abstract: There is provided an oscillation drive device that forms an oscillation loop with a vibrator for exciting a driving vibration on the vibrator.
    Type: Grant
    Filed: February 12, 2010
    Date of Patent: December 31, 2013
    Assignee: Seiko Epson Corporation
    Inventors: Naoki Yoshida, Masahiro Kanai
  • Patent number: 8618888
    Abstract: An apparatus comprising a first circuit and a second circuit. The first circuit may be configured to generate an output signal oscillating at a frequency in response to a first control signal and a second control signal. The second circuit may be configured to generate the second control signal in response to (i) an input voltage and (ii) the output signal. The second circuit (i) generates the second control signal by comparing a peak voltage of the output signal to the input voltage and (ii) adjusts an amplitude of the control signal in response to the comparison.
    Type: Grant
    Filed: July 14, 2009
    Date of Patent: December 31, 2013
    Assignee: LSI Corporation
    Inventor: Heung S. Kim
  • Patent number: 8610509
    Abstract: A method for generating an oscillator signal uses a multiphase oscillator having a plurality of input stages and a reference stage. Each input stage produces an input stage voltage that represents a phase for the oscillator. The input stage voltages produced by each of the input stages are compared to a reference voltage produced by the reference stage. An input stage having a maximum input stage voltage is selected and an output of the selected input stage having the maximum input stage voltage is changed. A current need of the oscillator is detected with a negative feedback loop coupled to the reference stage. An appropriate supply current is provided to each input stage with the negative feedback loop.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: December 17, 2013
    Assignee: Alpha and Omega Semiconductor Incorporated
    Inventors: Behzad Mohtashemi, Allen Chang
  • Patent number: 8570113
    Abstract: A method and circuitry for calibrating the gain of a VCO (voltage controlled oscillator) is disclosed. In one embodiment, a circuit includes a comparator configured to provide a first indication if the VCO gain is not within the specified gain range, and a second indication if the VCO is within the specified gain range. The circuit further includes a control unit configured to, upon occurrence of at least a first cycle of a clock signal, cause adjustment of the VCO gain responsive to receiving the first indication. For each one or more successive cycles of the clock signal, the control unit is configured to cause corresponding adjustments of the VCO gain until the comparator provides the second indication. The control unit is configured to discontinue adjustments to the VCO gain responsive to receiving the second indication.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: October 29, 2013
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Dennis M. Fischette
  • Patent number: 8570112
    Abstract: A MEMS oscillator having a feedback-type oscillation circuit including a MEMS resonator and an amplifier, a voltage control unit operable to control a bias voltage applied to an oscillating member of the MEMS resonator, and an auto gain control unit which receives an output from the amplifier and, based on a level of the output, to output an amplitude control signal for controlling a gain of the amplifier to the amplifier such that the level of the output from the amplifier comes to be a predetermined level, wherein the voltage control unit controls the bias voltage applied to the oscillating member based on an operating temperature of the MEMS resonator such that a peak gain of the MEMS resonator comes to have a predetermined value regardless of the operating temperature, and the voltage control unit derives the operating temperature of the MEMS resonator by monitoring the amplitude control signal.
    Type: Grant
    Filed: June 8, 2012
    Date of Patent: October 29, 2013
    Assignee: Panasonic Corporation
    Inventors: Takehiko Yamakawa, Tomohiro Iwasaki, Kunihiko Nakamura, Keiji Onishi
  • Patent number: 8552808
    Abstract: Embodiments of the present invention provide an oscillator having circuitry that measures the power dissipated in a resonator and circuitry that controls the power delivered to the resonator in response to the measured power. In some embodiments, the circuitry that measures the power dissipated in the resonator comprises circuitry that measures the voltage across the resonator, circuitry that measures the current through the resonator, and circuitry that calculates the power dissipated in the resonator based on the measured voltage and current.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: October 8, 2013
    Assignee: Tektronix, Inc.
    Inventors: Donald J. Delzer, Laszlo J. Dobos
  • Patent number: 8525605
    Abstract: A MEMS oscillator including: an oscillator unit being capable of outputting an output from an amplifier as an original oscillator signal that includes a feedback type oscillator circuit including a MEMS resonator and an amplifier, and an automatic gain controller receiving the output from the amplifier and controlling a gain of the amplifier based on a level of the output to maintain a level of the output from the amplifier constant; and a corrector unit that receives the original oscillator signal, that generates from the original oscillator signal a signal of a predetermined set frequency, and that outputs the generated signal of the predetermined set frequency as an output signal.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: September 3, 2013
    Assignee: Panasonic Corporation
    Inventors: Takehiko Yamakawa, Kunihiko Nakamura, Keiji Onishi
  • Patent number: 8525603
    Abstract: An oscillating signal generating device includes an oscillating circuit and a control circuit. The oscillating circuit includes: a resonator having a first terminal and a second terminal for generating an oscillating signal, a resistive element having a first terminal coupled to the first terminal of the resonator, and a second terminal coupled to the second terminal of the resonator, and an oscillating start-up circuit having an input terminal coupled to the first terminal of the resonator and an output terminal coupled to the second terminal of the resonator. The control circuit generates a control signal to change the oscillating start-up circuit into a disable mode from an enable mode when the oscillating circuit generates an oscillating output signal under an operation mode, and outputs the oscillating signal generated by the resonator as the oscillating output signal of the oscillating circuit.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: September 3, 2013
    Assignee: Silicon Motion Inc.
    Inventor: Shuo-Chun Hung
  • Patent number: 8493156
    Abstract: According to an exemplary embodiment, a high amplitude oscillation generator includes an LC tank circuit, a gain stage, a dynamic bias circuit, a bias current source, and a dynamic bias circuit receiving a current source feedback voltage and outputting a gain stage bias voltage. The dynamic bias circuit adjusts the gain stage bias voltage in response to a change in the current source feedback voltage after a start up of the LC tank circuit. The dynamic bias circuit thereby increases an amplitude of oscillations produced by the oscillation generator. The dynamic bias circuit can include an error amplifier, the error amplifier generating the gain stage bias voltage responsive to the current source feedback voltage. The current source feedback voltage can change with a voltage drop across the bias current source. The current source feedback voltage can also be received from an output of the oscillation generator.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: July 23, 2013
    Assignee: Broadcom Corporation
    Inventor: Zhiheng Cao
  • Patent number: 8471644
    Abstract: A gain control circuit, suitable for controlling the amplitude of a voltage-controlled oscillator, includes a duty cycle detector, an analog-to-digital converter, and a function generator. The gain control circuit provides a digitally enabled negative feedback loop. The duty cycle detector generates an estimate of the amplitude. The function generator receives a target amplitude as well as a digital representation of the estimate of the amplitude. The function generator calculates a modified estimate and periodically compares the same to the target value to generate a control word. The control word is arranged to enable current sources in the voltage-controlled oscillator.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: June 25, 2013
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Robert Thelen, Herman H. Pang
  • Patent number: 8466754
    Abstract: The present invention is a method for reducing phase noise in oscillator signals. For example, the oscillator may be a low phase noise MEMS-based oscillator and may include a resonator (ex.—a MEMS resonator). Further, the resonator of the oscillator may be operated near a bifurcation point. Still further, the MEMS resonator may be parametrically pumped in such a way so as to redistribute the quadrature signal noise (ex.—phase noise) to in-phase noise (ex.—amplitude noise).
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: June 18, 2013
    Assignee: Rockwell Collins, Inc.
    Inventors: Vadim Olen, Jonathan A. Lovseth, Robert C. Potter, Robert A. Newgard, Roy H. Olsson, III, Kenneth E. Wojciechowski
  • Publication number: 20130093526
    Abstract: Reducing a gain of a VCO, which may be used in a serdes system, includes using an oscillator replicating the VCO. The oscillator frequency varies according to PVT conditions of circuit elements of the oscillator, which affect a speed of the circuit elements. A first circuit receives an output of the oscillator to produce a current that varies inversely proportionally to the oscillator frequency. A second circuit injects the current into a power supply line of the VCO. Thus, high VCO frequencies can be attained. By reducing the gain of the VCO, thermal noise contribution of the loop resistor and the loop capacitor required for desired loop bandwidth are reduced. During fast corner conditions, minimal current is injected into the VCO. During slow corner conditions, high current is injected into the VCO. These help keep VCTRL of the PLL loop close to a mid-rail operating region.
    Type: Application
    Filed: October 17, 2011
    Publication date: April 18, 2013
    Applicant: Texas Instruments Incorporated
    Inventor: Vishnu Ravinuthula
  • Patent number: 8378756
    Abstract: Some embodiments regard a method comprising: generating a current according to a movement of the MEMS device; the movement is controlled by a control signal; generating a peak voltage according to the current; and adjusting the control signal when the peak voltage is out of a predetermined range.
    Type: Grant
    Filed: May 18, 2010
    Date of Patent: February 19, 2013
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Ming-Chieh Huang, Chiang Pu, Chan-Hong Chern, Chih-Chang Lin, Yuwen Swei