Temperature Or Current Responsive Means In Circuit Patents (Class 331/176)
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Patent number: 8089323Abstract: Green Design is to save the resource and energy for earth. Applying the recycling of energy concept to the electrical and electronic device and circuit, we can save many nuclear power plants to save the earth and human society. Comparing with today power amplifier PA has only 10% efficiency, the high linearity and high efficiency power-managing amplifier PMA and differential power managing amplifier DPMA can have the power efficiency more than 95%. The recycling switch inductor drive power management unit PMUx gets rid of the switch loss and has power efficiency more than 99%. The Xtaless Clock generator based on on-chip gain-boost-Q LC tank and the Spurfree and Jitterless Frequency & Phase Lock Loop FPLL. The DPMA directly supply the power to the plasma light. The charge doped light mirror reduces the voltage swing, increases the power efficiency and operating speed of plasma light, projective TV, LaserCom.Type: GrantFiled: August 23, 2008Date of Patent: January 3, 2012Inventors: Min Ming Tarng, Mei Jech Lin, Eric Yu-Shiao Tarng, Alfred Yu-Chi Tarng, Angela Yu-Shiu Tarng, Jwu-Ing Nieh, Huang-Chang Tarng, Shun-Yu Nieh
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Patent number: 8085105Abstract: A constant-temperature type crystal oscillator includes: a crystal unit including a case main body including a first power source terminal on an outer bottom surface thereof; a surface-mounted oscillator; a temperature control circuit including a heating resistor and a temperature sensor; and a circuit substrate including a second power source terminal. One ends of the heating resistor and the temperature sensor are electrically connected to the second power source terminal. The first power source terminal of the surface-mounted oscillator and the one ends of the heating resistor and the temperature sensor are electrically connected to the second power source terminal of the circuit substrate. The first power source terminal of the surface-mounted oscillator is directly and electrically connected to, at least, the one end of the temperature sensor via an electrically-conducting path.Type: GrantFiled: November 13, 2009Date of Patent: December 27, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventor: Kenji Kasahara
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Patent number: 8081040Abstract: Aspects of the disclosure provide a voltage controlled oscillator. The voltage controlled oscillator can include a plurality of oscillation stages coupled together to generate an oscillation signal having an oscillation frequency. At least one oscillation stage of the plurality of oscillation stages can include a first portion driven by a first driving power that can be a function of a control voltage and a second portion driven by a second driving power that can be substantially independent of the control voltage. The first driving power can be provided by a first power rail in the form of a driving current that is a function of the control voltage. The second driving power can be provided by a second power rail in the form of a substantially constant voltage that is substantially independent of the control voltage.Type: GrantFiled: July 6, 2009Date of Patent: December 20, 2011Assignee: Marvell Israel (M.I.S.L) Ltd.Inventor: Shimon Avitan
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Patent number: 8076980Abstract: A temperature-compensated ring oscillator includes a control signal generator and a voltage controlled oscillator. The control signal generator is configured to generate at least one control signal, and includes at least one first resistor and second resistor. A first temperature coefficient of the first resistor is negative, and a second temperature coefficient of the second resistor is positive. The voltage controlled oscillator receives the control signal, outputs an oscillation signal, and has (2k+1) cascaded inverter units, where k?1. Each of the inverter units includes a first transistor, a second transistor and an inverter. The first transistor has a drain coupled to a first supply voltage and a gate to receive the control signal. The second transistor has a source to receive a second supply voltage and a gate to receive the control signal. The inverter is coupled between the first and the second transistors.Type: GrantFiled: January 19, 2010Date of Patent: December 13, 2011Assignee: Elite Semiconductor Memory Technology Inc.Inventor: Yi-Heng Liu
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Patent number: 8076983Abstract: A constant-temperature type crystal oscillator includes: a crystal unit including a case main body, in which two crystal terminals and two dummy terminals are provided on an outer bottom face thereof, and a crystal element housed in the case main body; an oscillator output circuit including an oscillating stage and a buffering stage; a temperature control circuit for keeping an operational temperature of the crystal unit; and a circuit substrate, on which circuit elements of the crystal unit, the oscillator output circuit and the temperature control circuit are installed. The temperature control circuit includes: heating chip resistors; a power transistor; and a temperature sensing element. Each of the dummy terminals is connected to a respective one of circuit terminals on the circuit substrate. At least one of the circuit terminals is connected to an electrically-conducting path, to which one terminal of the heating chip resistors is electrically connected, on the circuit substrate.Type: GrantFiled: September 16, 2009Date of Patent: December 13, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventor: Manabu Ito
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Patent number: 8076985Abstract: Provided is a voltage-controlled oscillator that can hold an oscillation frequency at a desired value when an oscillation frequency changes due to the temperature, without narrowing a variable range of the oscillation frequency, and a PLL circuit, an FLL circuit, and a wireless communication device, which use the voltage-controlled oscillator. A control voltage Vt is applied to a connection point Y between variable capacitors 121 and 122 included in a variable capacitance circuit 120. A control signal Fse1 is applied to a switching element 132 included in a capacitance switching circuit 130. A power-supply voltage Vdd is applied by a control section 170 to a connection point X between inductors 111 and 112 included in an inductor circuit 110. A voltage value of the power-supply voltage Vdd is controlled such that the oscillation frequency of the local oscillation signal is held at a constant regardless of a temperature change.Type: GrantFiled: March 19, 2010Date of Patent: December 13, 2011Assignee: Panasonic CorporationInventor: Takayuki Tsukizawa
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Patent number: 8076984Abstract: A periodic signal generating circuit which is dependent upon temperature for establishing a temperature independent refresh frequency is presented. The periodic signal generating circuit includes a reference voltage generating unit and a periodic signal generating unit. The reference voltage generating unit produces a reference voltage which exhibits a variable voltage level in response to temperature. The periodic signal generating unit produces a periodic signal in response to a set voltage to determine the reference voltage and an oscillation period, wherein a transition timing of the set voltage is controlled by the reference voltage. As a result the periodic signal has a relatively constant period which can be produced regardless of the temperature variation.Type: GrantFiled: June 12, 2009Date of Patent: December 13, 2011Assignee: Hynix Semiconductor Inc.Inventors: Ho Uk Song, Mi Hyun Hwang
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Patent number: 8072281Abstract: A substantially temperature-independent LC-based oscillator is achieved using an LC tank that generates a tank oscillation at a phase substantially equal to a temperature null phase. The temperature null phase is a phase of the LC tank at which variations in frequency of an output oscillation of the LC-based oscillator with temperature changes are minimized. The LC-based oscillator further includes frequency stabilizer circuitry coupled to the LC tank to cause the LC tank to oscillate at the phase substantially equal to the temperature null phase.Type: GrantFiled: August 21, 2009Date of Patent: December 6, 2011Assignee: Si-Ware Systems Inc.Inventors: Bassel Hanafi, Sherif Hosny, Ayman Ahmed
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Patent number: 8072282Abstract: A method for compensating an oscillation frequency, a device, and a phase locked loop (PLL) is applied in the LC oscillating loop, including: sending voltage control signals to one end of a variable capacitor of an LC oscillating loop to generate oscillating signals in the LC oscillating loop through the voltage control signals; obtaining variable bias voltage that reflects changes of external parameters; and sending the variable bias voltage to the other end of the variable capacitor to compensate changes to the oscillation frequency of oscillation signals generated in the LC oscillating loop. This invention compensates the changes to the oscillation frequency of the circuit that contains the LC oscillating loop and improves the stability of the circuit oscillation frequency by sending bias voltage to one end of the variable capacitor of the LC oscillating loop.Type: GrantFiled: January 25, 2010Date of Patent: December 6, 2011Assignee: Huawei Technologies Co., Ltd.Inventor: Hongquan Sun
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Patent number: 8069549Abstract: A quartz crystal device includes a crystal resonator element and a package including a plurality of components. The plurality of components are bonded using a metal paste sealing material containing a metallic particle having an average particle size from 0.1 to 1.0 ?m, an organic solvent, and a resin material in proportions of from 88 to 93 percent by weight from 5 to 15 percent by weight, and from 0.01 to 4.0 percent by weight, respectively, to hermetically seal the crystal resonator element in the package.Type: GrantFiled: March 19, 2008Date of Patent: December 6, 2011Assignee: Seiko Epson CorporationInventors: Yoji Nagano, Tatsuya Anzai, Hideo Tanaya
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Patent number: 8067992Abstract: Disclosed are various embodiments of temperature-compensated relaxation oscillator circuits that may be fabricated using conventional CMOS manufacturing techniques. The relaxation oscillator circuits described herein exhibit superior low temperature coefficient performance characteristics, and do not require the use of expensive off-chip high precision resistors to effect temperature compensation. Positive and negative temperature coefficient resistors arranged in a resistor array offset one another to provide temperature compensation in the relaxation oscillator circuit.Type: GrantFiled: June 6, 2008Date of Patent: November 29, 2011Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.Inventors: Alex Jianzhong Chen, Gim Eng Chew, Tong Tee Tan, Kok Chin Pan
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Patent number: 8064578Abstract: Systems for providing a tune master caller identification (ID) device include a telecommunications network and a caller device configured to provide caller identification information for an incoming telephone call, and a tune master caller ID device that is coupled to a telephone device. The tune master caller ID device receives caller identification information, associates a tune with the caller identification information, and plays the tune associated with the caller identification. The telephone device coupled to the tune master caller ID device provides telephone call processing capabilities. Other systems and methods are also provided.Type: GrantFiled: April 9, 2009Date of Patent: November 22, 2011Assignee: AT&T Intellectual Property I, L.P.Inventors: Edward Michael Silver, Linda Ann Roberts, Hong Thi Nguyen
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Patent number: 8063711Abstract: A crystal oscillator emulator integrated circuit includes a first temperature sensor configured to sense a first temperature of the crystal oscillator emulator integrated circuit. The memory is configured to (i) store calibration parameters and (ii) select at least one of the calibration parameters based on the first temperature. A semiconductor oscillator is configured to generate an output signal, wherein (i) the output signal has a frequency and an amplitude and (ii) the frequency is based on the at least one of the calibration parameters. An amplitude adjustment module is configured to (i) compare the amplitude to a predetermined amplitude and (ii) generate a control signal to adjust the amplitude based on the comparison.Type: GrantFiled: September 7, 2010Date of Patent: November 22, 2011Assignee: Marvell World Trade Ltd.Inventor: Sehat Sutardja
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Patent number: 8059425Abstract: An integrated circuit module with temperature compensation crystal oscillator (TCXO) applying to an electronic device comprises: one substrate having one top surface; one temperature compensation crystal oscillator (TCXO) disposed on the top surface; at least one chip disposed on the top surface; one encapsulating piece formed on the top surface for covering the TCXO and the chip. As above-described structure, TCXO is prevented from exchanging heat due to the temperature difference so that the stability of the TCXO is improved.Type: GrantFiled: May 28, 2008Date of Patent: November 15, 2011Assignee: Azurewave Technologies, Inc.Inventors: Chung-Er Huang, Chien-Yu Huang
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Patent number: 8058941Abstract: A voltage control type temperature compensation piezoelectric oscillator, includes: a voltage control type oscillation circuit; an automatic frequency control (AFC) circuit outputting a control voltage for controlling an oscillation frequency of the voltage control type oscillation circuit based on an external control voltage; a temperature compensation voltage generating circuit generating a temperature compensation voltage; and a gain variable circuit varying a gain of the temperature compensation voltage. In the oscillator, the gain variable circuit is controlled by the control voltage outputted from the AFC circuit, and the oscillation frequency of the voltage control type oscillation circuit is controlled by an output voltage of the gain variable circuit.Type: GrantFiled: November 16, 2009Date of Patent: November 15, 2011Assignee: Seiko Epson CorporationInventors: Shigehisa Kurogo, Masayuki Ishikawa, Atsushi Kiyohara, Takehiro Yamamoto, Norihito Matsukawa
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Publication number: 20110273333Abstract: A piezoelectric oscillator includes: a piezoelectric resonator; a storage unit that stores temperature compensation data used for specifying frequency-temperature characteristics of the piezoelectric resonator therein; a temperature compensation circuit; a voltage-controlled oscillation circuit that oscillates the piezoelectric resonator and controls an oscillation frequency of the piezoelectric resonator based on an oscillation control voltage; and a power source control unit that controls so as to supply a power source voltage to the temperature compensation circuit or so as not to supply the power source voltage to at least a part of the temperature compensation circuit based on a control signal transmitted from the outside, wherein the temperature compensation voltage is supplied as the oscillation control voltage to the voltage-controlled oscillation circuit in synchronization with a period during which the power source voltage is supplied to the temperature compensation circuit.Type: ApplicationFiled: April 26, 2011Publication date: November 10, 2011Applicant: SEIKO EPSON CORPORATIONInventors: Katsuyoshi TERASAWA, Manabu OKA
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Patent number: 8049572Abstract: An oven-controlled crystal oscillator includes a circuit board, a crystal unit surface-mounted on the circuit board, and a temperature control circuit that maintains operating temperature of the crystal unit constant. The temperature control circuit includes a heating resistor, a power transistor that supplies power to a heating resistor, and a temperature sensitive resistor that detects temperature of the crystal unit. The heating resistor is formed, as a film resistor, on a surface of the circuit board in an area thereof in which the crystal unit is located. The temperature sensitive resistor is provided on the circuit board as a film resistor.Type: GrantFiled: February 19, 2009Date of Patent: November 1, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventors: Junichi Arai, Kenji Kasahara
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Patent number: 8044740Abstract: A temperature compensated CMOS RC oscillator circuit changes the source-bulk voltage to stabilize the MOSFET's threshold voltage variation over temperature using a resistor and temperature-correlated bias current. The MOSFET's source is connected to ground through a resistor. This temperature-correlated bias current also runs through this resistor. When temperature increases, the bias current also increases, which increases the MOSFET's source-bulk voltage. The increased source-bulk voltage helps to stabilize the threshold voltage of MOSFET at high temperature. A power saving logic is also embedded in this oscillator to achieve higher frequency at lower power consumption. In the present invention, there is no high gain op amp or high speed comparator, which makes the resultant oscillator to be low power design and which can be integrated into a single chip with other system.Type: GrantFiled: September 3, 2009Date of Patent: October 25, 2011Assignee: S3C, Inc.Inventor: Zhineng Zhu
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Patent number: 8044722Abstract: To provide a highly stable oscillation frequency control circuit wherein the frequency thereof is corrected, an adequate range of the input levels of external reference signals is determined in accordance with temperature characteristics in detecting the external reference signal, and the control voltage to a VCO is controlled within and outside the adequate range. An oscillation frequency control circuit includes a selection switch that connects the phase comparator to the loop filter in an external reference synchronization mode and that connects the fixed voltage supplying circuit to the loop filter in a fixed voltage mode, and a CPU that switches the selection switch to the external reference synchronization mode or to the fixed voltage mode based on whether the detected voltage of an external reference signal level is within or outside of the adequate range.Type: GrantFiled: November 12, 2009Date of Patent: October 25, 2011Assignee: Nihon Dempa Kogyo Co., LtdInventor: Hiroki Kimura
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Patent number: 8044736Abstract: Timing oscillators as well as related methods and devices are described. A timing oscillator may include a mechanical resonating structure with major elements and minor elements coupled to the major element. The timing oscillator can generate stable signals with low phase noise at very high frequencies which allows a timing oscillator to be used effectively in a number of devices including computers and mobile phones for time and data synchronization purposes. The signal generated by the timing oscillator can be tuned using a driver circuit and a compensation circuit.Type: GrantFiled: April 29, 2008Date of Patent: October 25, 2011Assignee: Sand9, Inc.Inventors: Pritiraj Mohanty, Klaus Juergen Schoepf, Alexei Gaidarzhy, Guiti Zolfagharkhani, David M. Chen, Matthew J. Crowley
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Patent number: 8040197Abstract: A crystal oscillator includes a crystal unit and a voltage-variable capacitive element that is connected to the crystal unit in series, the crystal oscillator varying an oscillation frequency by applying a control voltage between terminals of the voltage-variable capacitive element and by varying a series equivalence capacitance at a side of the oscillator circuit when observed between terminals of the crystal unit. The crystal oscillator further includes a first resistor and a second resistor for dividing the control voltage. At least one of the first resistor and the second resistor is a temperature sensing resistor, the resistance of which changes depending on a temperature, so as to correct frequency temperature characteristics of the oscillation frequency.Type: GrantFiled: October 27, 2009Date of Patent: October 18, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventor: Junichi Arai
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Patent number: 8037431Abstract: A design structure embodied in a machine readable medium used in a design process includes an interleaved voltage-controlled oscillator, including a ring circuit of main logic inverter gates; a plurality of delay elements connected in parallel with a selected sequence of the main logic inverter gates; wherein each delay element comprises a feedforward section, comprising controls for regulating signal transmission through feedforward elements responsive to one or more control voltages; and a proportional section for regulating signal transmission through at least one logic inverter gate; at least one temperature compensation circuit responsive to a compensating voltage input that is proportional to temperature; an electronic circuit in communication with the temperature compensation circuit and configured to provide a voltage signal responsive to temperature; an amplifier in connection with the electronic circuit to amplify the voltage signal; and a DC offset generator configured to adjust the voltage of theType: GrantFiled: May 23, 2008Date of Patent: October 11, 2011Assignee: International Business Machines CorporationInventors: David W. Boerstler, Eskinder Hailu, Jieming Qi, Mike Shen
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Patent number: 8031024Abstract: A wireless communication terminal includes a crystal oscillator, a transceiver and circuitry. The crystal oscillator belongs to a specified type of crystal oscillators in which a dependence of an output frequency as a function of temperature has one or more parameters that vary among the crystal oscillators belonging to the specified type. The transceiver is arranged to perform signal processing operations to a communication signal using the output frequency of the crystal oscillator. The circuitry is arranged to determine a characteristic of the output frequency of the crystal oscillator at one or more operating temperatures, to compute the one or more parameters for the crystal oscillator based on the determined characteristic and the operating temperatures, and to correct a frequency error in the output frequency of the crystal oscillator using the dependence and the computed parameters.Type: GrantFiled: February 27, 2009Date of Patent: October 4, 2011Assignee: Marvell International Ltd.Inventor: Alex Zaslavsky
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Patent number: 8026460Abstract: Provided is a control circuit for a thermostatic oven in an oven controlled crystal oscillator, which is capable of further improving stability of an oscillation frequency. A control circuit in which a thermistor whose resistance value changes according to a temperature outputs a signal according to the ambient temperature of the thermostatic oven inside the oscillator, an operational amplifier outputs a signal according to a difference between the output of the thermistor and a reference signal, a power transistor amplifies the output of the operational amplifier, and a heater generates heat based on a collector voltage of the power transistor, is provided with a temperature sensor circuit having a transistor with a base to which the output of the operational amplifier is input. The control circuit outputs a collector voltage of the transistor as an internal temperature signal which changes according to a temperature inside the oscillator.Type: GrantFiled: July 18, 2008Date of Patent: September 27, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventors: Manabu Ito, Takeshi Uchida
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Patent number: 8022780Abstract: Techniques for compensating for the effects of temperature change on voltage controlled oscillator (VCO) frequency are disclosed. In an embodiment, an auxiliary varactor is coupled to an LC tank of the VCO. The auxiliary varactor has a capacitance controlled by a temperature-dependant control voltage to minimize the overall change in VCO frequency with temperature. Techniques for generating the control voltage using digital and analog means are further disclosed.Type: GrantFiled: April 22, 2008Date of Patent: September 20, 2011Assignee: QUALCOMM IncorporatedInventors: Mazhareddin Taghivand, Conor Donovan, Jeongsik Yang, Sang-Oh Lee
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Patent number: 8013683Abstract: A constant-temperature type crystal oscillator includes: a crystal unit that is installed on one principal surface of a circuit substrate, and chip resistors, which function as heating elements, and which are installed on the other principal surface of the circuit substrate so as to face a principal surface of the crystal unit, the chip resistors heating up the crystal unit to keep an operational temperature of the crystal unit constant. A heating metal film facing the principal surface of the crystal unit is provided on the one principal surface of the circuit substrate. A heat conducting material is interposed between the principal surface of the crystal unit and the heating metal film to perform thermal coupling therebetween. The heating metal film is thermally coupled to electrode terminals of the chip resistors via a plurality of electrode through holes.Type: GrantFiled: September 1, 2009Date of Patent: September 6, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventor: Junichi Arai
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Patent number: 7999628Abstract: This invention includes a bias origination section configured to originate an original bias voltage; a comparison section configured to compare the original bias voltage and a comparison voltage, and output a comparison result; a resistive divider section composed by a resistance circuit including a variable resistor section having a resistor and a switch, and configured to generate the comparison voltage; a bias decision control section configured to determine bias decision data for controlling a resistance value of the variable resistor section so as to bring the comparison voltage close to the original bias voltage, based on a comparison result of the comparison section; and a storage section configured to hold the bias decision data and also output the comparison voltage as a bias voltage by controlling a resistance value of the variable resistor section based on the held bias decision data, thereby generating a low-noise bias with a small area.Type: GrantFiled: September 9, 2009Date of Patent: August 16, 2011Assignee: Kabushiki Kaisha ToshibaInventor: Daisuke Miyashita
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Patent number: 7982550Abstract: An apparatus and a method for compensating for a mismatch in temperature coefficients of two oscillator frequencies to match a desired frequency ratio between the two oscillator frequencies over a temperature range. In one embodiment of a temperature sensor, first and second oscillators of different temperature characteristics are coupled to a differential frequency discriminator (DFD) circuit. The DFD circuit compensates for the different characteristics in order to match a frequency difference between the first and second frequencies over a temperature range.Type: GrantFiled: July 1, 2008Date of Patent: July 19, 2011Assignee: Silicon LaboratoriesInventors: Emmanuel P. Quevy, Manu Seth
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Patent number: 7982551Abstract: A VCO circuit includes a temperature detector circuit, a voltage generator circuit, a switch, a resonance circuit and an oscillator. The temperature detector detects a temperature, and the voltage generator circuit generates a voltage for coarse adjustment corresponding to the detected temperature and outputs the same voltage. The switch selects one of a DC voltage for fine adjustment and the voltage for coarse adjustment. The resonance circuit includes a varactor diode having a capacitance value adjusted based on the voltage selected by the switch, capacitors and an inductor, and has a predetermined resonance frequency. The oscillator generates an oscillation signal having an oscillation frequency corresponding to the resonance frequency by using the resonance circuit and outputs the same signal.Type: GrantFiled: March 23, 2007Date of Patent: July 19, 2011Assignee: Panasonic CorporationInventors: Mineyuki Iwaida, Yasuo Oba, Takeshi Fujii
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Patent number: 7982549Abstract: A system may include a first circuit configured to generate a first clock having a first period of oscillation, and a second circuit configured to generate a second clock having a second period of oscillation, where the difference (?T) between the first period of oscillation and the second period of oscillation remains within a specified limit even during variations in temperature and/or during variations in the supply voltage. The system may further include a control circuit, which may receive the first clock and the second clock, and adjust, according to ?T, a first target parameter corresponding to a first number of cycles of the first clock, when a current cycle count of the second clock reaches a second target parameter corresponding to a second number of cycles of the second clock.Type: GrantFiled: December 4, 2009Date of Patent: July 19, 2011Assignee: Atheros Communications, Inc.Inventors: Paul J. Husted, Manev Luthra, Wen-Hsing Chen
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Patent number: 7975364Abstract: A method for producing a tuning-fork type crystal vibrating piece relates to a crystal tuning fork comprising a basal portion, a first vibrating arm, and a second vibrating arm, wherein both arms extend from the basal portion. The method for producing a crystal tuning fork comprises a step of forming a first metallic film into a shape including the contours of the basal portion, the first vibrating arm and second vibrating arm on a first surface of a quartz wafer; a step of forming a second metallic film on the second surface opposite to the first surface of the quartz wafer into a shape covering at least a root area near the basal portion between the first vibrating arm and the second vibrating arm, and a step of wet-etching the quartz substrate in etching solution after forming the first and second metallic films.Type: GrantFiled: October 5, 2007Date of Patent: July 12, 2011Assignee: Nihon Dempa Kogyo Co., Ltd.Inventor: Takehiro Takahashi
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Patent number: 7969251Abstract: A divider control circuit includes a first and a second delta sigma modulator configured to generate a divider control signal for a fractional-N divider and a fractional signal indicative of a phase error in the divider output. The fractional signal is supplied for control of an interpolator circuit. The divider control circuit may be implemented as a look-ahead circuit where two or more divider control signals and fractional signals are generated during a single cycle to allow the divider control circuit to be run at a reduced clock rate.Type: GrantFiled: June 23, 2010Date of Patent: June 28, 2011Assignee: Silicon Laboratories Inc.Inventors: Zhuo Fu, Susumu Hara
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Publication number: 20110133846Abstract: A temperature invariant digitally controlled oscillator is disclosed. The digitally controlled oscillator is configured to generate an output clock with stable frequency. The temperature invariant digitally controlled oscillator comprises a digitally controlled oscillator, a temperature sensor, a temperature decision logic circuit, and a temperature conditioner. The digitally controlled signal is provided to adjust the oscillation frequency of the digitally controlled oscillator by changing its capacitances. The stabilization of the silicon temperature is achieved with the temperature sensor, the temperature decision logic circuit, and the temperature conditioner.Type: ApplicationFiled: December 3, 2009Publication date: June 9, 2011Inventor: Hong-Yean Hsieh
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Patent number: 7952435Abstract: Embodiments of a phase lock loop and a method for compensating a temperature thereof can output an initial tuning digital value for a voltage controlled oscillator configured to output a desired phase lock loop frequency compensated according to a temperature change. Embodiments of a phase lock loop and a method for compensating a temperature thereof can simultaneously perform a digital coarse tuning and an analog fine tuning to compensate for a temperature in a limited time.Type: GrantFiled: October 29, 2007Date of Patent: May 31, 2011Assignee: GCT Semiconductor, Inc.Inventors: Seung-Wook Lee, Joonbac Park, Jeong Woo Lee, Su Won Kang, Kyeongho Lee
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Publication number: 20110121909Abstract: A temperature compensation method for a piezoelectric oscillator including a piezoelectric vibrator having a frequency temperature characteristic with a hysteresis characteristic, and an oscillation circuit which oscillates the piezoelectric vibrator and outputs an oscillation signal, wherein, to a temperature compensation circuit which can calculate a quantity of temperature compensation using frequency temperature information indicating a temperature characteristic of an oscillation frequency of the piezoelectric vibrator and temperature information of the piezoelectric vibrator at the time of oscillation of the oscillation signal, the oscillation signal and the frequency temperature information are outputted, includes: calculating, as the frequency temperature information, an intermediate value between elevated-temperature frequency temperature information of the piezoelectric vibrator that is generated in the case where ambient temperature of the piezoelectric vibrator is elevated, and lowered-temperatureType: ApplicationFiled: November 16, 2010Publication date: May 26, 2011Applicant: SEIKO EPSON CORPORATIONInventors: Kensaku ISOHATA, Masayuki ISHIKAWA
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Patent number: 7936227Abstract: A reference clock circuit (170), has a low-power mode, in which the frequency consumption is reduced, and including an internal counter, accumulating time spent in low-power mode. The circuit includes a crystal resonator (60), an oscillator circuit (70), and a temperature compensation circuit (80), providing a stable clock output (85). During low-power mode temperature compensation can be switched off. The circuit further provides a wakeup signal (107) after a preset time in low-power mode.Type: GrantFiled: May 30, 2008Date of Patent: May 3, 2011Assignee: QUALCOMM IncorporatedInventor: Phil Young
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Patent number: 7928811Abstract: Systems and methods are disclosed herein for using a switched mode TCXO or VC-TCXO in a satellite navigation receiver where the switched mode TCXO or VC-TCXO may operate either in an active compensation mode to compensate for temperature induced frequency error or in a second fixed compensation mode where the TCXO or VC-TCXO is not compensated for temperature. The switched mode TCXO or VC-TCXO is operated in the active compensation mode when satellite acquisition performance may be improved from a reduction in the range of oscillator frequency error. The switched mode TCXO or VC-TCXO may be switched to operate in the fixed compensation mode when satellite tracking performance is sensitive to discontinuities in the phase, frequency, and/or frequency rate of the oscillator clock when temperature compensation is applied.Type: GrantFiled: December 22, 2008Date of Patent: April 19, 2011Assignee: SiRF Technologies, Inc.Inventor: Keith Brodie
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Patent number: 7924109Abstract: Provided is a MEMS oscillation circuit which performs temperature compensation of a MEMS resonator with a simple circuit, which is mild so that an output clock does not have jitter, and which makes the range of fluctuations of a reference frequency from a reference value equivalent to a range of digital processing. The MEMS oscillator includes a MEMS resonator, a temperature measurement unit for measuring a temperature and outputting a detected voltage corresponding to the temperature, and a bias voltage control circuit for applying the MEMS resonator with a bias voltage which changes the resonant frequency of the MEMS resonator in a manner opposite to a change of the resonant frequency of the MEMS resonator due to temperature change correspondingly to the detected voltage.Type: GrantFiled: February 20, 2009Date of Patent: April 12, 2011Assignee: Seiko Instruments Inc.Inventor: Kensuke Ogasawara
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Patent number: 7924110Abstract: In various embodiments, the invention provides a clock generator and/or a timing and frequency reference, with multiple operating modes, such power conservation, clock, reference, and pulsed modes. The various apparatus embodiments include a resonator adapted to provide a first signal having a resonant frequency; an amplifier; a temperature compensator adapted to modify the resonant frequency in response to temperature; and a process variation compensator adapted to modify the resonant frequency in response to fabrication process variation. In addition, the various embodiments may also include a frequency divider adapted to divide the first signal having the resonant frequency into a plurality of second signals having a corresponding plurality of frequencies substantially equal to or lower than the resonant frequency; and a frequency selector adapted to provide an output signal from the plurality of second signals.Type: GrantFiled: May 4, 2009Date of Patent: April 12, 2011Assignee: Integrated Device Technology, Inc.Inventors: Michael Shannon McCorquodale, Scott Michael Pernia, Amar Sarbbasesh Basu
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Patent number: 7924104Abstract: A method for compensating a clock bias in a Global Navigation Satellite System (GNSS) receiver includes deriving at least one clock drift value comprising a first clock drift value corresponding to a first time point, and calculating the clock bias according to the at least one clock drift value and at least one interval within the time period between the first time point and a specific time point after the first time point. An apparatus for compensating a clock bias in a GNSS receiver is also provided.Type: GrantFiled: August 21, 2008Date of Patent: April 12, 2011Assignee: Mediatek Inc.Inventors: Kung-Shuan Huang, Yu-Chi Yeh
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Patent number: 7920663Abstract: Adjusting a local frequency source is disclosed. A local frequency comparison data is compared with a received frequency comparison data, wherein the local frequency comparison data reflects a difference, if any, between a locally measured AC frequency and a frequency generated using the local frequency source. The local frequency source is adjusted based at least in part on a result of the comparison.Type: GrantFiled: November 20, 2006Date of Patent: April 5, 2011Assignee: Broadcom CorporationInventor: William M. Stevens
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Patent number: 7920032Abstract: An oscillator device for generating an oscillator signal, includes a heater arrangement, a first switching element, a temperature sensor, signal process means, and voltage controlled oscillator; an output of the temperature sensor being connected to an input of the signal processing means, and an output of the signal processing means being connected to an input of the voltage controlled oscillator. The first switching element is arranged for receiving the oscillator signal from the voltage controlled oscillator and for providing a heater drive signal to either a first heater element or a second heater element of the heater arrangement based on the oscillator signal. The signal processing means comprise a synchronous demodulator.Type: GrantFiled: January 30, 2006Date of Patent: April 5, 2011Assignee: Stichting voor de Technische WetenschappenInventors: Kofi Afolabi Anthony Makinwa, Johan Frederik Witte
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Patent number: 7914204Abstract: A temperature sensor includes: a first oscillator that generates a first frequency signal; a second oscillator that generates a second frequency signal; a multiplexer that selectively passes the first frequency signal and the second frequency signal; and a frequency-to-digital converter that converts a frequency difference between the first frequency signal and the second frequency signal into a digital code.Type: GrantFiled: April 1, 2008Date of Patent: March 29, 2011Assignee: Korea University Industrial & Academic Collaboration FoundationInventors: Chulwoo Kim, Janghoon Song, Gilwon Yoon, Sangdon Jung
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Patent number: 7902927Abstract: The present invention provides a system and method for achieving a calibration-free primary atomic clock standard operating at the 0-0 transition free-atom frequency, thus creating a primary frequency standard, with attributes that include scalable to chip-scale dimensions and power consumption.Type: GrantFiled: June 18, 2009Date of Patent: March 8, 2011Assignee: SRI InternationalInventors: Timothy Davis, Sterling McBride, Alan Braun, William Happer
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Publication number: 20110050353Abstract: A temperature compensated CMOS RC oscillator circuit changes the source-bulk voltage to stabilize the MOSFET's threshold voltage variation over temperature using a resistor and temperature-correlated bias current. The MOSFET's source is connected to ground through a resistor. This temperature-correlated bias current also runs through this resistor. When temperature increases, the bias current also increases, which increases the MOSFET's source-bulk voltage. The increased source-bulk voltage helps to stabilize the threshold voltage of MOSFET at high temperature. A power saving logic is also embedded in this oscillator to achieve higher frequency at lower power consumption. In the present invention, there is no high gain op amp or high speed comparator, which makes the resultant oscillator to be low power design and which can be integrated into a single chip with other system.Type: ApplicationFiled: September 3, 2009Publication date: March 3, 2011Applicant: S3C, INC.Inventor: Zhineng ZHU
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Patent number: 7893785Abstract: Circuits, methods, apparatus, and code that provide low-noise and high-resolution electronic circuit tuning. An exemplary embodiment of the present invention adjusts a capacitance value by pulse-width modulating a control voltage for a switch in series with a capacitor. The pulse-width-modulated control signal can be adjusted using entry values found in a lookup table, by using analog or digital control signals, or by using other appropriate methods. The capacitance value tunes a frequency response or characteristic of an electronic circuit. The response can be made to be insensitive to conditions such as temperature, power supply voltage, or processing.Type: GrantFiled: May 2, 2008Date of Patent: February 22, 2011Assignee: Marvell World Trade Ltd.Inventors: Jody Greenberg, Sehat Sutardja
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Patent number: 7893774Abstract: A VCO driving circuit and a frequency synthesizer wherein the impedance viewed from a VCO control terminal is reduced to prevent the VCO phase noise characteristic from degrading. A VCO driving circuit and a frequency synthesizer having the VCO driving circuit, which comprises a coarse adjustment DAC that receives a digital data, which has a coarse adjustment frequency, to output an analog signal; a fine adjustment DAC that receives a digital data, which has a fine adjustment frequency, to output an analog signal; a low response speed LPF5 that removes noise from the output signal from the coarse adjustment DAC and then provides the resultant signal as an input to a VCO control terminal; a high response speed LPF7 that converts the output signal from the fine adjustment DAC to a voltage, thereby smoothing the signal; a resistor that connects an input stage of the LPF5 to that of the LPF7; and a capacitor used for providing a capacitive coupling such that the output of the LPF7 is added to that of the LPF5.Type: GrantFiled: June 29, 2010Date of Patent: February 22, 2011Assignee: Nihon Dempa Kogyo Co., LtdInventors: Yasuo Kitayama, Hiroki Kimura, Naoki Onishi, Nobuo Tsukamoto
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Patent number: 7889014Abstract: One embodiment in accordance with the invention is a method that can include utilizing a ring oscillator module to determine a process corner of an integrated circuit as fabricated that includes the ring oscillator module. The impedance of an output driver of the integrated circuit can be altered based on the process corner of the integrated circuit as fabricated.Type: GrantFiled: November 20, 2007Date of Patent: February 15, 2011Inventors: Steven T. Stoiber, Stuart Siu
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Patent number: 7889018Abstract: An oscillator utilizes two current sources that have the same temperature and VDD dependency so they generate the same current in changing conditions. Therefore, there is very low VT dependency. The resistor and fringe capacitor temperature coefficient are very low and opposite so they compensate for each other. A comparator with a short period of operation also minimizes VT dependency.Type: GrantFiled: December 21, 2007Date of Patent: February 15, 2011Assignee: SanDisk CorporationInventor: Tomer Shaul Elran
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Patent number: 7889016Abstract: An integrated oscillator (10), for an integrated circuit, comprises i) first (CI1) and second (CI2) compensated inverters mounted in series and each comprising first (PI11;PI21) and second (PI12;PI22) plain inverters mounted in parallel and comprising transistors having channel lengths respectively shorter and longer than an optimal channel length, the first compensated inverter (CI1) having input and output terminals respectively connected to first (N1) and second (N2) nodes and the second compensated inverter (CI2) having input and output terminals respectively connected to the second node (N2) and to a third node (N3), ii) a resistor (R) having a chosen resistance value and comprising first and second terminals connected respectively to the first (N1) and second (N2) nodes, and iii) a capacitor (C) comprising first and second terminals connected respectively to the first (N1) and third (N3) nodes, and having a chosen capacitance value to charge and discharge oneself in order to periodically deliver a clockType: GrantFiled: August 3, 2006Date of Patent: February 15, 2011Assignee: ST-Ericsson SAInventor: Zhenhua Wang