Abstract: An apparatus for generating an oscillating signal that includes a circuit to accelerate the time in which an oscillating signal reaches a defined steady-state condition from a cold start. The apparatus includes an oscillating circuit to generate an oscillating signal; a first circuit to supply a first current to the oscillating circuit; and a second circuit to supply a second current to the oscillating circuit, wherein the first and second currents are adapted to reduce the time duration for the oscillating signal to reach a defined steady-state condition. The apparatus may be useful in communication systems that use low duty cycle pulse modulation to establish one or more communications channels, whereby the apparatus begins generating an oscillating signal at approximately the beginning of the pulse and terminates the oscillating signal at approximately the end of the pulse.

Abstract: An oscillator circuit includes a current source comprising an amplifier, a first resistor, a second resistor, and a third inverter whose input and output are connected and coupled with an input of the amplifier. The amplifier is configured to generate a first current flowing through the first resistor and the second resistor.

Abstract: A voltage-controlled oscillator has an oscillation frequency controlled through a voltage applied across ends of a variable-capacitance element. The voltage-controlled oscillator has a frequency control bias circuit which applies to a first end of the variable-capacitance element a voltage for frequency control according to a control voltage, a first current source which generates a first current according to the control voltage, a second current source which generates a second current according to temperature, independent of the control voltage, a converting resistor which converts a current, obtained by adding together the first and second currents, into a voltage, and a temperature compensation bias circuit which applies to the second end of the variable-capacitance element a voltage for temperature compensation according to the voltage produced by the converting resistor.

Abstract: 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.

Abstract: Various systems and methods for drift compensation are disclosed. As one example, a system for compensating drift in a control circuit is disclosed that includes at least two control signals. One of the control signals is provided by a circuit that is susceptible to drift. This control signal is provided both to a systems or device under control, and to a detection circuit. The detection circuit is operable to detect a drift in the control signal. In addition, the detection circuit provides another control signal that varies as a function of the drift in the received control signal.

Abstract: The oscillation circuit includes an output current mirror, a P-N complementary current mirror, a P-type current mirror and an N-type current mirror. The P-N complementary current mirror has the same structure as the output current mirror but has current that is only 1/k times the current of the output current mirror, wherein k is greater than 1. The P-type current mirror connects to the P-N complementary current mirror, and has current that is m times the current of the P-N complementary current mirror, where m is greater than 1. The N-type current mirror has one end connected to the P-type current mirror and another end connected to the output current mirror. The N-type current mirror has current that is n times the current of the P-type current mirror, where m × n k ? 1 , and n is greater than 1.

Abstract: Methods and apparatus for controlling frequency in a crystal oscillator are provided that allows for continued reception of GPS signal solution in a continuous high G environment. One method comprises measuring G-forces asserted on the crystal oscillator, determining a shift in frequency of the crystal oscillator due to the measured G-forces, determining a temperature that would shift the crystal oscillator's frequency back to a rate that would occur without the measured G-forces, and changing the temperature of the crystal oscillator based on the determined temperature to shift the crystal oscillator's frequency back to a rate that would occur if the G-forces were not present.

Abstract: Crystal oscillator control and calibration is disclosed. Temperature and frequency control circuits included on a printed circuit board (PCB) comprising a crystal oscillator are used to determine, for each of a plurality of set points in a range of sensed internal temperatures sensed by an internal temperature sensing circuit or device located adjacent to the oscillator in a thermally insulated region of the PCB, a corresponding compensation required to be applied to maintain a desired oscillator output frequency. The PCB is configured to use at least the determined compensation values and a sensed internal temperature to determine during operation of the PCB a compensation, if any, to be applied to maintain the desired oscillator output frequency.

Abstract: A clock synthesis circuit includes a delta sigma modulator that receives a divide ratio and generates an integer portion and a digital quantization error (a fractional portion). A fractional-N divider divides a received signal according to a divide control value corresponding to the integer portion and generates a divided signal. A phase interpolator adjusts a phase of the divided signal according to the digital quantization error to thereby reduce noise associated with the fractional-N divider.

Abstract: In a method for manufacturing a quartz crystal unit, a quartz crystal tuning fork resonator is formed by etching a quartz crystal wafer to form a quartz crystal tuning fork base and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. The quartz crystal tuning fork resonator has a piezoelectric constant e?12 within a range of 0.12 C/m2 to 0.19 C/m2 in the absolute value to drive the quartz crystal tuning fork resonator. An electrode is disposed on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes disposed on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes disposed on the side surfaces of the second quartz crystal tuning fork tine. The quartz crystal tuning fork resonator is mounted on a mounting portion of a case.

Abstract: A device and method for determining a thermal absorption of a part of an integrated circuit (IC) are provided. A specially designed ring oscillator including a non-silicided poly-silicon resistor is used for the determination. The parameters of the ring oscillator are designed/tuned so that a delay of the ring oscillator varies predominantly with a variation in a resistance of the non-silicided poly-silicon resistor. The dimensions of the non-silicided poly-silicon resistor are large enough so that the resistance of the non-silicided poly-silicon resistor is immune to the small process variations of the poly-silicon length and width. The resistance of the non-silicided poly-silicon resistor varies with the thermal absorption of the part of the IC. As such, the thermal absorption of the part of the IC may be determined based on the delay of the ring oscillator.

Abstract: The present invention relates to an integrated circuit for a temperature compensated crystal oscillator having an external crystal. The integrated circuit comprises a temperature compensation having one fixed or at least two selectable 3rd and/or 4th and/or 5th and/or higher order temperature compensation functions for at least one specific type of external crystal. The temperature compensation can be calibrated at one temperature, in other words without use of temperature variation, by means of an external voltage or current source overdriving a respective temperature-dependent voltage or current supplied from an internal temperature sensor to the temperature compensation.

Abstract: A temperature detector circuit using a MOS transistor capable of reducing manufacture variation of a mobility and realizing stable output characteristics which are not affected by temperature dependency may be offered. In one example, the temperature detector circuit includes a pair of depression type transistors to output a voltage which is proportional to temperature from a connecting point of a source of a first transistor and a drain of a second transistor. The transistors are the same conducted type of current and are formed in different channel size, which are connected between power supplies in series, and have a configuration in which first transistor's gate and source are connected each other and a first transistor's drain is connected with a second power supply and second transistor's gate and drain are connected each other and a second transistor's source is connected with a first power supply.

Abstract: A system and method for providing temperature compensation in a oscillator component (such as a crystal oscillator component) that includes a closely-located temperature sensing device. The crystal oscillator component in example systems and methods is exposed to a temperature profile during a calibration procedure. Temperature and frequency data are collected and applied to coefficient generating function according to a temperature compensation model to generate a set of coefficients that are used in the temperature compensation model in an application device. The generated coefficients are stored in a coefficient memory accessible to an application device during operation.

Abstract: A voltage-controlled oscillator including a voltage-controlled oscillation section, a frequency control bias circuit, a temperature compensation bias circuit, and a temperature compensation bias generation circuit. The temperature compensation bias generation circuit has a transistor having its collector or drain connected to the temperature compensation bias circuit, a first resistor having one end connected to the collector or drain of the transistor and having another end that is grounded, a second resistor having one end connected to the base or gate of the transistor, a base or gate bias application terminal connected to another end of the second resistor, a third resistor having one end connected to the emitter or source of the transistor, and an emitter or source bias application terminal connected to another end of the third resistor.

Abstract: A surface mount type temperature-compensated crystal oscillator includes a crystal blank; an IC chip integrating an oscillation circuit using the crystal blank and a temperature compensation mechanism of compensating frequency temperature characteristics of the crystal blank; and a substantially rectangular parallelepiped container body for surface mounting having a first recess of housing the crystal blank and a second recess of housing the IC chip. Respective side surfaces corresponding to the long sides of the container body are provided with crystal inspection terminals for inspecting oscillation characteristics of the crystal blank and respective side surfaces corresponding to the short sides are provided with data writing terminals for writing temperature compensation data to the temperature compensation mechanism.

Abstract: Systems involving temperature compensation of voltage controlled oscillators are provided. In this regard, a representative system incorporates: a voltage controlled oscillator (VCO) having a tuning port and a phase-locked loop (PLL); and a temperature dependent voltage source. The VCO selectively exhibits one of a coarse tuning mode in which the temperature dependent voltage source is electrically connected to the VCO tuning port, and a locked mode in which the temperature dependent voltage source is not electrically connected to the VCO tuning port such that the PLL controls the frequency of the VCO.

Abstract: In various embodiments, the invention provides a discrete clock generator and/or a timing and frequency reference using an LC-oscillator topology, having a frequency controller to control and provide a stable resonant frequency, which may then be provided to other, second circuitry such as a processor or controller. Frequency stability is provided over variations in a selected parameter such as temperature and fabrication process variations. The various apparatus embodiments include a sensor adapted to provide a signal in response to at least one parameter of a plurality of parameters; and a frequency controller adapted to modify the resonant frequency in response to the second signal. In exemplary embodiments, the sensor is implemented as a current source responsive to temperature fluctuations, and the frequency controller is implemented as a plurality of controlled reactance modules which are selectively couplable to the resonator or to one or more control voltages.

Abstract: In an oscillation apparatus formed by a ring oscillator including an odd number of inverters (more than two inverters) connected in a ring, each of the inverters having one drive MOS transistor and one load MOS transistor, a constant voltage generating circuit is adapted to generate a constant voltage corresponding to a threshold voltage of the drive MOS transistor, and a voltage-to-current converting circuit is adapted to convert the constant voltage into load currents. Each of the load currents flows through the load MOS transistor of one of the inverters.

Abstract: An interleaved voltage-controlled oscillator (VCO) is disclosed. The VCO includes a ring circuit comprising a series connection of main logic inverter gates, a plurality of delay elements connected in parallel with a selected sequence of the main logic inverter gates, at least one temperature compensation circuit comprising a logic inverter gate in series connection with one or more field effect transistors, the field effect transistor responsive to a compensating voltage input that is proportional to temperature, and an electronic circuit in signal communication with the at least one temperature compensation circuit and configured to provide a voltage signal responsive to temperature. Each delay element includes a feedforward section, comprising controls for regulating signal transmission through feedforward elements responsive to one or more control voltages, and a proportional section, comprising controls for regulating signal transmission through at least one logic inverter gate.

Abstract: A voltage controlled oscillator includes a resonant circuit, a trimming capacitor and a full adder. The resonant circuit includes a negative resistor, an inductor and an oscillation frequency setting capacitor having a variable capacitance according to a controlled voltage based on a oscillation frequency data. The trimming capacitor is connected in parallel to the oscillation frequency setting capacitor. The trimming capacitor has capacitors each of which has a variable capacitance according to an input signal thereof. The full adder is connected to the trimming capacitor. The full adder generates the input signal based on frequency information and an automatic proofreading value received thereto.

Abstract: The electronic device (100) of the invention comprises a semiconductor device (30) and a low-pass filter (20), which are present in a stacked configuration, and which together include a phase locked loop. The low-pass filter is preferably embodied by vertical trench capacitors, and preferably comprises a drift compensation part. The device (100) can be suitably provided in an open loop architecture. In a preferred embodiment, the low-pass filter comprises a large capacitor (C2) and a small capacitor (C1) connected in parallel, the large capacitor (C2) being connected in series with a resistor (R1).

Abstract: A free running clock circuit includes a switching circuit for switching between first and second logic states at a predetermined frequency based upon a trip voltage the switching circuit has a programmable temperature profile associated therewith. The switching circuit includes a comparator circuit that has first and second comparators. The first and second comparators have a reference input connected to receive the trip voltage, and the output of the comparators change logic states between a first logic state and a second logic state when the other input of the comparator passes the trip voltage. The first and second comparators have a programmable offset voltage enabling programming of the programmable voltage supply profile of the switching circuit. An RC timing circuit defines when the outputs of the comparators switch between the first and second logic states by providing a feedback to the other inputs of the two comparators.

Abstract: In a voltage controlled oscillator, a resonant circuit generates a resonant frequency in response to a tuning voltage. A differential oscillator includes first and second transistors differentially cross-coupled to the resonant circuit. The first and second transistors supply energy to the resonant circuit to oscillate the resonant frequency from the resonant circuit, thereby generating first and second oscillation signals having a phase difference of 180 degree. Also, the first and second transistors adjust the first and second oscillation signals to a uniform level in response to a body bias voltage. In addition, an output level detector detects a level of the first and second oscillation signals from the differential oscillator and supplies the body bias voltage corresponding to the detected level to a body of each of the first and second transistors.

Abstract: An oscillator circuit includes: oscillating transistors; a resonance circuit that includes varactor diodes each having a cathode to which a control voltage for controlling an oscillation frequency is applied and that is coupled between a collector and a base of each of the oscillating transistors; and a bias power supply that applies the bias voltages to the anodes of the varactor diodes. The bias voltages are given negative temperature characteristics, and a variation in the oscillation frequency caused by a change in the capacitance values of the varactor diodes due to a temperature variation is corrected by varying the bias voltages corresponding to the temperature variation.

Abstract: A constant temperature crystal oscillator includes on a circuit substrate: a surface-mount crystal resonator which is provided with two crystal terminals as mount terminals and a dummy terminal on the bottom surface, and has a metal cover; an oscillation circuit element which forms an oscillation circuit together with the crystal resonator; and a temperature control element which keeps a constant operation temperature of the crystal resonator, in which the temperature control element includes at least a heating chip resistor, a power transistor for supplying electric power to the chip resistor, and a temperature sensitive resistor for detecting the operation temperature of the crystal resonator, wherein a dummy terminal on the substrate side of the circuit substrate for connection to the dummy terminal of the crystal resonator is connected to a resistor terminal on the substrate side to which the temperature sensitive resistor is connected through a conductive path.

Abstract: 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.

Abstract: An automatic temperature compensated real-time clock (RTC) chip includes a clock portion having a crystal oscillator block including crystal compensation circuitry adapted to be coupled to a crystal. The crystal compensation circuitry includes a non-linear capacitor DAC including a plurality of load capacitors, wherein the load capacitors have respective switches which switch respective ones of the load capacitors to change a parallel resonance frequency (fp) generated by the oscillator block. The capacitor DAC is arranged so that Analog Trimming (ATR) bits received cause an arrangement of the switches to provide a non-linear change in overall load capacitance to result in a linear relationship between fp and the ATR bits. A temperature sensor block is coupled to the crystal for measuring a temperature of at least the crystal. An A/D converter is coupled to the temperature sensor for outputting a digital temperature signal representative of the temperature of the crystal.

Abstract: The temperature of a remote portion of device having a microelectromechanical oscillator is modulated to create oscillation of the oscillators. In one embodiment, a localized heat source is placed on a device layer of a multilayered stack, consisting of device, sacrificial and substrate layers. The localized heat source may be a laser beam in one embodiment. The oscillator is supported by the device layer and may be formed in the device layer in various embodiments. The oscillator may be spaced apart from the localized heat source.

Abstract: In an EEPROM of a microcomputer, data is stored for determining a communication rate CMR for fixing the data transmission time of one frame managed by a communication circuit on the basis of an oscillation output characteristic of a CR oscillating circuit that varies in accordance with temperature. CPU reads out data stored in EEPROM in accordance with the temperature detected by a temperature detecting circuit, and sets the determined communication CMR into the communication circuit.

Abstract: Circuits and methods for compensating a variable oscillator for process and/or operational variations. The circuit generally comprises (a) a replica oscillator, (b) a counter configured to count pulses of the replica oscillator and to produce a count signal, and (c) a compensation circuit configured to provide an adjustment signal to the variable oscillator in accordance with the count signal. The method generally comprises the steps of (a) counting the number of pulses of a replica oscillator signal, and (b) providing an adjustment signal to the variable oscillator in accordance with the number of pulses counted. The present invention advantageously provides a largely digital method to compensate a variable oscillator for process, voltage, and temperature variations.

Abstract: A crystal oscillator that outputs an oscillation output signal of an oscillator circuit oscillated by a crystal resonator as a resonation source via a buffer circuit, includes: a plurality of waveform output circuits provided in the buffer circuit, each converting, when inputted, the oscillation output signal into a different waveform and outputting the converted signal; a circuit selection switch that selects any one of the plurality of waveform output circuits as a waveform output circuit of the buffer circuit; and a memory circuit that stores data used by the circuit selection switch to select any one of the waveform output circuits.

Abstract: A lead wire led-out type crystal oscillator of constant temperature type for high stability is disclosed, which includes a heat supply body that supplies heat to a crystal resonator from which a plurality of lead wires are led out, to maintain the temperature constant. The heat supply body includes a heat conducting plate which has through-holes for the lead wires and is mounted on the circuit board, and which faces, and is directly thermally joined to, the crystal resonator and a chip resistor for heating which is mounted on the circuit board adjacent to the heat conducting plate, and is thermally joined to the heat conducting plate.

Abstract: An oscillation circuit formed in a single semiconductor chip, wherein a first source voltage is supplied to a first power supply terminal, a second source voltage different from the first source voltage is supplied to a second power supply terminal, a voltage regulator receives the voltage from the first power supply terminal and outputs a source voltage, a voltage controlled oscillation circuit is supplied with a source voltage from the voltage regulator, a current source circuit is connected to the second power supply terminal, the voltage regulator, the voltage controlled oscillation circuit and the current source circuit are inserted in series between the first and second power supply terminals, and the current supplied to the voltage controlled oscillation circuit from the voltage regulator flows in the current source circuit.

Abstract: 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.

Abstract: In a device for detecting the temperature of an oscillator crystal 2, arranged on a carrier, in particular in a mobile radio apparatus, the detected temperature should be as exact as possible a replica of the temperature to which the oscillator crystal 2 is subjected. For this purpose, a temperature sensor 7 is arranged on the carrier 1 in such a way that it is subjected to the same ambient temperature as the oscillator crystal 2 or the oscillator-crystal housing 2?. The temperature sensor 7 and the oscillator crystal 2 are located so as to be electrically parallel.

Abstract: An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator.

Abstract: There are many inventions described and illustrated herein.

Abstract: There is provided a phase locked loop circuit which receives a reference signal having a reference frequency and a first signal having a first frequency, compares phases of the reference signal and first signal, applies a control voltage based on a phase comparison result to an input terminal of a voltage controlled oscillator to generate a second signal having an oscillation frequency and output the second signal from an output terminal, and supplies the second signal to a divider to divide the frequency of the second signal and output the first signal; and a controller which generates and supplies a control signal to the voltage controlled oscillator, wherein the voltage controlled oscillator has an arrangement in which a coil and variable capacitance are connected in parallel between the input terminal and output terminal, and one of a plurality of capacitances is selectively connected between the input terminal and output terminal by a switch in parallel with the variable capacitance, and ON/OFF of the sw

Abstract: A refresh control circuit includes a reference voltage generating circuit and an oscillator unit. The reference voltage generating circuit generates a reference voltage based on a variation in a drain-to-source voltage of a field effect transistor according to a temperature variation. The oscillator unit generates a pulse signal having a period that varies according to the temperature based on the reference voltage. The refresh period is thereby controlled automatically, in accordance with the operating temperature.

Abstract: There are many inventions described and illustrated herein.

Abstract: There are many inventions described and illustrated herein.

Abstract: A double oven crystal oscillator (DOCXO) is disclosed which is highly stable by incorporating means to reduce the effects of ambient pressure changes on the frequency of the oscillator. The oscillator crystal is mounted in a temperature controlled inner oven to reduce the effects on the frequency stability of the oscillator. The oscillator circuitry and all circuitry associated with the inner oven is mounted in good thermal contact with the inner oven. A Faraday shield at ground potential is placed over the oscillator circuitry to minimize the effects of stray capacitance between the oscillator components and the case wall of the inner oven. The effects of minor deformations in the case walls within the oscillator caused by ambient pressure changes and other factors causing pressure changes are thereby greatly minimized.

Abstract: Provided is an oscillator including a logic signal generator and a clock generator. The logic signal generator generates a first logic signal and a second logic signal that have the same period but have different logic level transition timing. The clock generator generates a clock signal in response to the first logic signal and the second logic signal. The oscillator compensates for an amount of variation of a reference current using a compensation current, thereby maintaining a constant period of the clock signal.

Abstract: A ring oscillator setting apparatus and method depending on an environmental change of an image formation apparatus is provided. The apparatus includes a plurality of ring oscillators for generating different oscillation frequencies. The apparatus further includes a loopspeed detection unit to detect a loopspeed representing the number of pulses generated at the oscillation frequency by one of the ring oscillators selected from the plurality of ring oscillators for a predetermined unit time. Moreover, a state sensing unit is provided to detect a state of system environment of the image formation apparatus. A setting control unit is also provided to select and set one of the ring oscillators selected corresponding to change of the loopspeed detected from the loopspeed detection unit among the plurality of ring oscillators in response to the detected state of the state sensing unit.

Abstract: An apparatus, system and method are provided for low-latency start-up of a free-running harmonic oscillator. The exemplary apparatus embodiment comprises a first and second current sources to generate first and second currents; a bias current monitor adapted to detect a magnitude of the second current and to provide a control signal when the magnitude of the second current is equal to or greater than a predetermined magnitude; and a bias controller adapted to switch the first current from the oscillator and to switch the second current to the oscillator in response to the control signal. a reference voltage generator, a comparator, and a bias controller. Exemplary embodiments include reference voltage generator, a comparator, and a bias controller.

Abstract: The phase-locked loop circuit includes a gain setting circuit for setting a gain of a voltage controlled oscillator, and a time-constant setting circuit for setting a time constant, which is determined by the amount of current in a charge pump circuit and a capacitance value of a loop filter. The gain setting circuit sets the gain to a predetermined value, and the time-constant setting circuit sets the time constant to a predetermined value, whereby the loop band width of the phase-locked loop circuit is set to a desired value.

Abstract: The present invention provides a current controlled oscillator comprising a first section providing a first differential output and a second section providing a second differential output. A loading structure comprised of resistive and reactive elements electrically connects the first differential output with the second differential output. The resistive and reactive elements have values chosen such that the resistive elements substantially extend the linear operating frequency range of the current controlled oscillator. Transistors of the loading structure have which are tied to a power supply rejection ratio compensation section for compensating for variations in power supply voltage.

Abstract: A self-refresh module includes an oscillator configured to provide a first signal having a first frequency, a trimming divider configured to trim the first signal to provide a second signal having a second frequency, and a temperature sensor configured to sense a temperature of the memory device and provide a temperature signal. The self-refresh module includes a temperature look-up table configured to receive the temperature signal and provide a third signal based on the temperature signal, and a temperature divider configured to provide a self-refresh pulse signal based on the second signal and the third signal.

Abstract: A temperature compensated piezoelectric oscillator includes: an oscillation circuit that drives a piezoelectric element with a current; a direct-current-stopping fixed capacitor; a frequency-temperature compensated circuit that compensates the deviation of an oscillation frequency caused by a change of temperature; and a piezoelectric transducer which includes a piezoelectric element driven in a prescribed frequency; where the above elements are connected serially.