Oscillators inventions 12/05

20050285686 - Circuit for driving a voltage controlled oscillator for frequency modulation: A circuit provides an output signal for modulating the oscillation frequency of a voltage-controlled oscillator (VCO) in response to a control signal where the VCO includes a first voltage-controlled variable capacitance device for varying the oscillation frequency of the VCO according to the output signal. The circuit includes a charge...

20050285687 - Method and apparatus for noise compensation in an oscillator circuit: A variable capacitance circuit includes a first and a second capacitor. A switch having an associated first nonlinear capacitance, selectively couples the first and second capacitors. To compensate for the first nonlinear capacitance, a second nonlinear capacitance is coupled to the switch that has a capacitance value responsive to a...

20050285685 - Phase error cancellation: A noise cancellation signal is generated for a fractional-N phase-locked loop by supplying a divide value to a first delta sigma modulator and generating a divide control signal in a first delta sigma modulator to control a divide value of a feedback divider in the phase-locked loop. The first delta...

20050285688 - Phase moulation apparatus, polar modulation transmission apparatus, wireless transmission apparatus and wireless communication apparatus: A phase modulation apparatus is provided whereby excellent RF phase modulation signals can be obtained even when the modulation sensitivity of a voltage controlled oscillator varies. Phase modulation apparatus 100 has: phase detector 105 that performs phase detection with respect to an RF phase modulation signal outputted from VCO 101;...

20050285689 - Crystal oscillator circuit with activation control: A CMOS Pierce crystal oscillator. A clock generator with activation control, for generating a clock signal. The clock generator comprises an amplifier, a shaping circuit and a diagnostic circuit. The amplifier is capable of being coupled to an external oscillation source through an input pad and an output pad to...

20050285690 - Crystal oscillator: A quartz crystal oscillator in which phase noise is reduced includes: a resonance circuit having a quartz crystal unit and a split capacitor connected to the crystal unit; a transistor for oscillation having its base connected to the node of the crystal unit and the split capacitor; an output line...

20050285691 - Surface mounting crystal oscillator: The present invention relates to a surface mounting crystal oscillator in which an IC chip, a crystal element, and a circuit component are connected together by wire bonding and are housed within a main container having a concave section. The main container has a pair of opposing inner wall step...

20050285692 - Frequency synthesizer: Method for stabilizing the frequency of a frequency synthesizer by means of a reference oscillator unit coupled to a voltage controlled oscillator (VCO) and a frequency synthesizer, wherein the synthesizer is provided with a phase locked loop (PLL) to stabilize the operation of the voltage controlled oscillator, wherein the reference...

20050280475 - Charge pump of a phase locked loop with switchable system bandwidth and method for controlling such a charge pump: A charge pump of a phase locked loop and method thereof, includes a first current source that supplies a first additive partial current to a node, a first current sink that draws a first subtractive partial current from the node, a second current source that supplies a second additive partial...

20050280474 - Method of reducing the fractional spurious and a fractional n-pll oscillator reducing the fractional spurious: A method for reducing the fractional spurious in a fractional N-PLL oscillator comprising a phase comparator having nonlinear elements and a variable frequency oscillator that responds to the low frequency component of output signals of the phase comparator and with which reference signals and signals obtained by dividing the output...

20050280473 - Phase locked loop with a modulator: The invention provides a phase locked loop having a modulator which is based on a ΣΔ fractional N phase locked loop. In the forward path of the PLL, the output of the oscillator has an additional frequency divider which provides the output frequency of the PLL in a plurality of...

20050280476 - Filter control apparatus and filter system: A filter control apparatus which controls a frequency variable filter capable of changing a transmission band width by controlling a capacitance of at least a portion of a plurality of voltage variable capacitors connected in series and parallel to a resonator has an input unit, and a filter control circuit....

20050280477 - Versatile system for accelerated stress characterization of semiconductor device structures: The present invention provides a system (200) for performing accelerated stress characterization of a given transistor (204). Inverter circuits, formed from the given transistor, are disposed in series with one another (202). A plurality of signal taps is operatively associated with each gap between adjacent inverter circuits. Selective circuitry is...

20050280478 - Low thermal drift, tunable frequency voltage controlled oscillator: An oscillator comprising a cascode configured device having first, second and third terminals, a plurality of resonators and first circuitry coupled between the plurality of resonators and the second terminal of the cascode configured device. The first circuitry is preferably operable as an evanescent mode buffer to compensate for changes...

20050280479 - Circuits and methods of temperature compensation for refresh oscillator: A memory device has refresh cycles to refresh memory cells of the memory device. The time interval between one refresh cycle to the next refresh cycle is a refresh interval. The refresh interval depends on a frequency of an oscillating signal. A refresh timer adjusts the frequency of the oscillating...

20050275471 - Clock generator and its control method: To present a clock generator capable of spreading the spectrum of oscillation frequency by simple control in a small additional circuit, and its control method. A phase locked loop circuit is provided from a frequency phase comparator 11, an output clock signal PO is outputted from a voltage control oscillator...

20050275470 - Low power and low timing jitter phase-lock loop and method: A phase-lock loop generates an output clock signal from an input clock signal. The output clock signal is coupled through a clock tree and is fed back to a phase detector, which compares the phase of the output clock signal to the phase of the input clock signal. The output...

20050275467 - Oscillator: A voltage controlled current source outputs oscillator drive current and oscillator equivalent current. A signal oscillator outputs first source oscillation signal and second source oscillation signal. An amplifier outputs first amplification oscillation signal and second amplification oscillation signal. First switch circuit and second switch circuit output first current oscillation signal...

20050275468 - Oscillator: A voltage controlled current source outputs oscillator drive current and oscillator equivalent current. A signal oscillator outputs first source oscillation signal and second source oscillation signal. A differential amplifier outputs first amplification oscillation signal and second amplification oscillation signal. First switch circuit and second switch circuit output first current oscillation...

20050275469 - Quadrature voltage controlled oscillators with phase shift detector: In wireless application there is made use of a quadrature oscillators that generate signals that are capable of oscillating at quadrature of each other. The quadrature oscillator is comprised of two differential modified Colpitts oscillators. A capacitor bank allows for the selection of a desired frequency from a plurality of...

20050275472 - Precise phase detector: A digital phase detector with a master stage having imbalanced latching devices with intentional input-referred offset for determining which one of a pair of input signals is leading the other and a slave stage connected to the master stage imbalanced latching devices and which slave stage is transparent when ones...

20050275473 - Pll architecture: A phase locked loop (PLL) circuit comprising: feedback division circuitry for receiving an output signal, the feedback division circuitry arranged to divide the output signal by a first division factor in a first mode of operation, and a second division factor in a second mode of operation....

20050275474 - Voltage controlled oscillator: The voltage controlled oscillator comprises an oscillating system wherein two variable capacitors are alternately connected. The capacitances of these two capacitors vary respectively in the same direction as the voltage that is applied thereto and in the opposite direction. Replacing one variable capacitor by the other is performed automatically when...

20050275475 - Method and apparatus for time measurement: A method is provided for accurate time measurement. Time is first measured with a first oscillator. At designated intervals, a second oscillator is activated for a period of time based on the first oscillator. The second oscillator is more accurate than the first oscillator. Pulses are then counted from the...

20050275477 - Methods and apparatus for calibrating gm-z: In one embodiment of the present invention, an apparatus includes a plurality of gain stages each having a gain greater than one, and which are coupled to create a positive feedback at an oscillation frequency. The gain stages may be formed of transconductance gain stages which may be coupled together...

20050275476 - Voltage-controlled oscillators: A voltage-controlled oscillator (VCO) comprising an odd number of delay stage circuits. Each delay stage circuit operates between supply voltages VDD and VSS (VDD>VSS) and comprises (1) an input node, (2) an output node, (3) an inverting circuit, and (4) an electric discharge path coupling the output node to VSS....

20050275478 - Voltage controlled oscillator, and pll circuit and wireless communication apparatus using the same: A voltage controlled oscillator comprises a parallel resonance circuit including an inductor circuit, a variable capacitance circuit, and a high-frequency switch circuit, a negative resistance circuit and a frequency control section, and a frequency tuning sensitivity control section. The frequency control section shifts a band of an oscillation frequency by...

20050275479 - Low noise yig oscillator based phase locked loop: A low phase noise YIG oscillator based phase locked loop couples an output frequency to a delay line discriminator to provide a phase noise feedback signal to a wideband tuning port of the YIG oscillator. A delay line in the delay line oscillator may be implemented with either a resonant...

20050275480 - Frequency selective oscillator, electronic instrument implementing the same, and method of adjusting frequency control characteristics: A frequency selective oscillator including: a plurality of piezoelectric elements having oscillation frequencies that are different from each other; a plurality of switching sections provided to the plurality of piezoelectric elements at both a signal input side and a signal output side of each of the plurality of piezoelectric elements...

20050270108 - Method and apparatus for calibration of a low frequency oscillator in a processor based system: Method and apparatus for calibration of a low frequency oscillator in a processor based system. A method for calibrating an on-chip non-precision oscillator. An on-chip precision oscillator is provided having a known frequency of operation that is within an acceptable operating tolerance. The on-chip precision oscillator is used as a...

20050270109 - Clock oscillator for reducing power consumption: A clock generator for use in a system on chip (SoC) includes a crystal oscillating unit, whose input terminal and an output terminal is respectively coupled to one terminal and the other terminal of a quartz vibrator, for generating a first clock; a ring oscillating unit for receiving an output...

20050270110 - Vco buffer circuit: A VCO buffer circuit comprising a first loading means receiving a first signal for loading the VCO at a first input node; a second loading means receiving a second signal for loading the VCO at a second input node; a third loading means coupled to said first loading means for...

20050270111 - Oscillation circuit and electronic equipment: An oscillation circuit comprises a SAW resonator having a pair of reflectors disposed on a piezoelectric substrate and a pair of IDTs which are set up in parallel between the pair of reflectors and which are constituted by teeth-of-a-comb electrodes; an inverter to which the pair of IDTs are connected...

20050270112 - Arranging a crystal to generate an oscillating signal: A crystal is loaded with capacitance in such a way that it begins to oscillate at a desired frequency with a resonance circuit (2). Capacitive voltage division is carried out with a voltage divider to at least one terminal (3) of the crystal (1). From the voltage divider, the signal...

20050270113 - Method for manufacturing quartz crystal resonator: A quartz crystal tuning fork resonator is manufactured with a fundamental mode of vibration and a second overtone mode of vibration each comprised of a flexural mode of an inverse phase. A merit value M1 of the fundamental mode of vibration is greater than a merit value M2 of the...

20050270114 - Voltage control oscillator having modulation function: There is provided a VCO having a modulation function capable of easily constituting a correction circuit which can obtain a predetermined modulation degree even when element irregularities are present. A modulation current terminal is connected to an anode side connection point of a first and a second varactor diode. A...

20050264366 - Open-loop start-up method for a resonating device: A system employing a resonating device and a controller implements a method involving an establishment by the controller of open-loop oscillations of the resonating device at a resonating frequency of the resonating device, and an establishment by the controller of closed-loop oscillations of the resonating device based on the open-loop...

20050264368 - Phase-control circuit arrangement and method for operating said circuit arrangement: A circuit arrangement includes a phase locked loop configured to produce a controlled frequency. The phase locked loop has an actuating input and a control loop output, with it being possible to tap off the frequency at the control loop output. In addition, a frequency meter is provided, which is...

20050264367 - Phase-locked loop with a pulse generator, and method for operating the phase-locked loop: The phase-locked loop has a pulse generator has a phase detector which is intended to compare a reference signal with an oscillator signal, and a detector output for tapping off a phase comparison signal. The pulse generator is used to produce a pulse-width-modulated pulse signal and has a generator output,...

20050264369 - Loop filter integration in phase-locked loops: A phase-locked loop and method are disclosed. One method embodiment includes providing a dual path filter of a phase-locked loop, the dual path filter consisting of passive components, and summing control signals in the dual path filter using the passive components....

20050264370 - Reference oscillator: A receiver uses an adaptive algorithm to tune a low-cost crystal oscillator according to a temperature compensation profile so as to produce a precision master reference frequency despite temperature, initial tolerance, and aging effects. An automatic frequency control system also tunes the crystal oscillator. The adaptive algorithm adjusts the temperature...

20050264371 - Differential voltage controlled oscillator using complementary transistors cross-coupled in series, and transceiver using the same: A differential voltage controlled oscillator comprises first and second transistors having opposite magnitudes and directions of currents flowing to a third electrode from a second electrode corresponding to a voltage between first and second electrodes; and a resonance circuit coupled to the second electrodes of the first and second transistors...