Abstract: A thermoelectric device transfers heat away from or toward an object using the Peltier effect. In some embodiments, the length of at least one thermoelectric element is at least ten times greater than a combined average cross-sectional dimension, orthogonal to the length, of two thermoelectric elements.

Abstract: A MEMS circuit comprises a MEMS device arrangement with temperature dependent output; a resistive heating circuit; and a feedback control system for controlling the resistive heating circuit to provide heating in order to maintain a MEMS device at a constant temperature. The heating is controlled in dependence on the ambient temperature, such that a MEMS device temperature is maintained at one of a plurality of temperatures in dependence on the ambient temperature. This provides power savings because the temperature to which the MEMS device is heated can be kept within a smaller margin of the ambient temperature.

Abstract: There is provided an oscillator capable of lowering the power supply voltage without degrading the phase noise, while employing the conventional circuit configuration. According to one aspect of the present invention, there is provided an oscillator comprising: an oscillation circuit; a bias generation circuit for generating a bias signal to drive the oscillation circuit; and a booster circuit for boosting a power supply voltage to generate a boosted voltage for driving the bias generation circuit. In addition, the oscillation circuit, the bias generation circuit, and the booster circuit are provided in a single IC chip, and the booster circuit may receive the power supply voltage VDD from the power supply arranged at the exterior of the IC chip.

Abstract: A method in a mobile communication device includes: measuring a first temperature associated with a crystal configured to provide a reference signal having a frequency; measuring a second temperature associated with a component that is coupled to the crystal by an electrically and thermally conductive line; and compensating, based upon the measuring of the first and second temperatures, for a change in the frequency of the reference signal of the crystal.

Abstract: An oscillator assembly including a base substrate with a cavity defining an insulative air pocket. A component substrate is seated on the base substrate. An oscillator and a combination heater/temperature control assembly are located on one side and a temperature control assembly is located on the opposite side and extends into the cavity. An interior lid covers and defines an oven for the oscillator and the heater/temperature control assembly. An exterior lid covers the interior lid. A thermal resistance/heat transfer element is seated on the oscillator for increasing thermal resistance and is seated on both the oscillator and the heater/temperature control assembly for decreasing thermal resistance.

Abstract: A temperature information generation circuit includes a temperature sensor (a first temperature detection section), a high-sensitivity temperature sensor (one or plural second temperature detection sections) having higher sensitivity than that of the temperature sensor, an output selection circuit, and a control section. The output selection circuit and the control section select a detection signal of the high-sensitivity temperature sensor upon supply of a power supply voltage, and then perform switching so as to select a detection signal of the temperature sensor at a predetermined timing.

Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; first and second heaters heating the gas cell; an exciting light source exciting the metal atom; a light detector detecting the exciting light; a substrate including a temperature controlling circuit for the heaters; a first wiring coupling the first heater and the substrate; a second wiring coupling the second heater and the substrate; and a third wiring coupling the first heater and the second heater. In the atomic oscillator, the gas cell includes a cylinder and windows sealing both ends of the cylinder and constituting an incident surface and an emitting surface on an optical path of the exciting light. The first and second heaters are respectively formed on the windows at an incident surface side and an emitting surface side and are made of transparent heating materials.

Abstract: An oscillator outputs a control signal to suppress an influence caused by temperature characteristic of f1 based on a differential signal corresponding to difference between an oscillation output f1 of a first oscillator circuit and an oscillation output f2 of a second oscillator circuit treated as a temperature detection value. A switching unit switches between a first state and a second state. The first state is a state where a first connecting end and a second connecting end are connected to a storage unit for access from an external computer to the storage unit. The second state is a state where the first connecting end and the second connecting end are connected to a first signal path and a second signal path such that the respective f1 and f2 are retrieved from the first connecting end and the second connecting end to an external frequency measuring unit.

Abstract: An oscillation circuit including a reference voltage generation circuit that adds a proportional-to-absolute-temperature (PTAT) output, which increases in proportion to an absolute temperature, to a complementary-to-absolute-temperature (CTAT) output, which decreases in proportion to an absolute temperature, to generate and output a reference voltage. The oscillation circuit generates an oscillation signal having a desired and fixed frequency.

Abstract: A semiconductor device with temperature control system. Embodiments of the device may include a MEMS chip including a first heater with a dedicated first temperature control loop and a CMOS chip including a second heater with a dedicated second temperature control loop. Each control loop may have a dedicated temperature sensor for controlling the thermal output of each heater. The first heater and sensor are disposed proximate to a MEMS device in the MEMS chip for direct heating thereof. The temperature of the MEMS chip and CMOS chip are independently controllable of each other via the temperature control loops.

Abstract: A physical section of an atomic oscillator includes: a gas cell in which gaseous metal atoms are sealed, and the gas cell includes a first window having optical transparency; a light source that emits excitation light toward the metal atoms through the first window; a first heating unit that disposes at the first window and that is located between the first window and the light source; and a Peltier element that is stacked on the first heating unit, that is located between the first heating unit and the light source, and that decreases a temperature of a side of the Peltier element facing the light source than a temperature of an opposite side of the Peltier element facing the gas cell.

Abstract: An oscillator includes a positive power supply node for providing a positive power supply voltage; a capacitor; and a constant current source providing a first constant current and coupled to the positive power supply node. The first constant current is independent from the positive power supply node. The oscillator also includes a charging current source configured to provide a second constant current to charge the capacitor, wherein the second constant current mirrors the first constant current. The oscillator further includes a constant current source inverter having a third constant current mirroring the first constant current. The constant current source inverter is configured to control the oscillator to transition state at a constant state transition voltage.

Abstract: Disclosed are microelectromechanical system (MEMS) devices and methods of using the same. In some embodiments, a MEMS device comprises a micro-oven comprising a MEMS oscillator configured to generate a reference signal. The device further comprises a control unit comprising at least one input node configured to receive a parameter set, where the parameter set comprises at least a first parameter indicative of a sensed ambient temperature, and where the control system is configured to (i) based on the parameter set, select from a plurality of pre-characterized operation temperatures an operation temperature for the MEMS oscillator, and (ii) generate a temperature-setting signal indicating the selected operation temperature. The device still further comprises a temperature control system communicatively coupled to the control unit and configured to (i) receive the temperature-setting signal and (ii) maintain the MEMS oscillator at the selected operation temperature.

Abstract: A semiconductor device includes: a resistance R whose resistance value varies in response to a substrate temperature variation; a resistance corrector that is coupled in series with the resistance R and switches its resistance value by a preset resistance step width to suppress a resistance value variation of the resistance R; a first voltage generator for generating a first voltage that varies in response to the substrate temperature; a second voltage generator for generating second voltages Vf1 to Vfn?1 for specifying the first voltage at a point when a switching operation of the resistance value of the resistance corrector is performed; and a resistance switch unit for switching the resistance value of the resistance corrector by comparing the first voltage and the second voltages Vf1 to Vfn?1.

Abstract: The present invention relates to a measurement method of dew-point in low temperature, and more specifically to a measurement method of accurately distinguishing dew-point and frost-point using a quartz crystal microbalance dew-point sensor in a low temperature of 0° C. or less. To this end, the present invention provides a measurement method of distinguishing dew and frost point using a quartz crystal microbalance dew-point sensor in low temperature, comprising the steps of: measuring a resonant frequency of a quartz crystal microbalance dew-point sensor while slowly dropping temperature; observing shock waves of the resonant frequency; and determining dew point or frost point through the observation of the resonant frequency and shock waves of the quartz crystal microbalance dew-point sensor.

Abstract: Disclosed an electronic device comprising an ovenized system containing a micro-electromechanical (MEM) resonator and a method for controlling such an MEM resonator. In one embodiment, the MEM resonator comprises a resonator body suspended above a substrate by means of at least a first and a second mechanical support forming a first and a second heating resistance, respectively, configured to heat the resonator body through Joules heating, biasing means configured to apply a bias voltage to the resonator body to enable vibration at a predetermined operating frequency, a temperature control system configured to control the temperature of the micro-electromechanical resonator, and an internal voltage monitoring system configured to monitor a voltage level of the resonator body.

Abstract: An oven controlled crystal oscillator includes a thermostatic bath, an inner circuit board, an outer circuit board, a heating element, and a temperature sensor. The inner circuit board comprising a crystal oscillation circuit is positioned inside the thermostatic bath and electrically connected with the outer circuit board via a pin. The outer circuit board has a temperature control circuit and a power supply circuit. The heating element and the temperature sensor electrically connect with the outer circuit board. A through slot is formed through the outer circuit board, and the thermostatic bath is inserted into the through slot. By inserting the thermostatic bath into the through slot of the outer circuit board, the height and the weight of the oven controlled crystal oscillator are reduced, the electric connection performance is enhanced, and thus the stability of the output frequency of the oven controlled crystal oscillator is improved.

Abstract: An atmosphere temperature at which a quartz-crystal oscillator and an oscillation circuit are placed is controlled in high accuracy, and an output frequency with high stability is obtained. If oscillation outputs of first and second quartz-crystal oscillators are set to f1 and f2, and oscillation frequencies of the oscillation outputs at a reference temperature are set to f1r and f2r, respectively, {(f2?f1)/f1}?{(f2r?f1r)/f1r} is calculated by a frequency difference detection unit. A digital value can be obtained by representing this value by 34-bit digital value, corresponding to a temperature. Therefore, this value is treated as a temperature detection value, a difference with a temperature set value is supplied to the loop filter, and the digital value therefrom is converted into a direct-current voltage to control a heater.

Abstract: One or more heating elements are disposed on a semiconductor substrate proximate a temperature sensitive circuit disposed on the substrate (e.g., bandgap circuit, oscillator). The heater element(s) can be controlled to heat the substrate and elevate the temperature of the circuit to one or more temperature points. One or more temperature measurements can be made at each of the one or more temperature points for calibrating one or more reference values of the circuit (e.g., bandgap voltage).

Abstract: Method and system (1) for stabilizing a temperature (Tcomp) of an integrated electrical component, placed in an oven, at a predefined temperature (Tset). The temperature of the integrated electrical component is sensed by means of temperature sensing means, comprising a first resp. second sensing element (61, 62) located in good thermal contact with the integrated electrical component, the first resp. second sensing elements (61, 62) having a first resp. second temperature dependent characteristic (63, 64), the second temperature dependency being different from the first temperature dependency such that the first and second characteristics (63, 64) intersect at the predefined temperature (Tset), and a sensing circuit (72) adapted for sensing the first and the second sensing elements (61, 62) and for supplying a first resp. second measurement signal (83, 84) indicative of the first resp.

Abstract: An oscillator assembly includes a substrate having a top surface, a bottom surface, and a plurality of side surfaces. At least one of the side surfaces has at least one castellation which is covered with conductive material and includes a lower end spaced from the bottom surface of the substrate. The space is defined by an elongate groove in the side surface which is devoid of conductive material and extends between the lower end of the castellation and the bottom surface of the substrate to eliminate the risk of a short circuit with any of the connection pads on a customer's motherboard. The oscillator assembly further incorporates an oscillator circuit in which a current limiting resistor is located in series between the power supply and the heater control circuit.

Abstract: A thermoelectric device transfers heat away from or toward an object using the Peltier effect. In some embodiments, the length of at least one thermoelectric element is at least ten times greater than a combined average cross-sectional dimension, orthogonal to the length, of two thermoelectric elements.

Abstract: A crystal oscillator is provided, which varies a frequency drift compensation according to a power consumption and compensates a frequency drift characteristic caused by heat. An adder is used to add a temperature compensation control voltage from a temperature compensation circuit, an oscillating frequency control voltage from an AFC circuit, and a frequency drift compensation voltage corresponding to the power consumption from a frequency drift compensation circuit. A voltage added by the adder is outputted to voltage-variable capacitor elements and, which respectively are connected to an input side and an output side of an inverter IC that is connected in parallel to a crystal oscillating unit.

Abstract: The present invention relates to an oven controlled crystal oscillator that can obtain stable oscillation frequency by reducing a temperature change in an oscillation element. The oven controlled crystal oscillator comprises; a heat-conducting plate mounted on one surface of a circuit board, a crystal resonator mounted on a surface of the heat-conducting plate opposite to the surface of the circuit board, an oscillation element constituting an oscillation circuit together with the crystal resonator, and a thermistor that detects temperature of the crystal resonator, a heating resistance which heats the crystal resonator, and a temperature control element including at least a power transistor, to constitute a temperature control circuit together with the thermistor and the heating resistance.

Abstract: A temperature-controlled crystal oscillating unit and oscillator are provided, which can stabilize an output frequency thereof, have firmness against shock of falling etc., and are suitable for miniaturization and mass production. A crystal blank for the temperature-controlled crystal oscillating unit is formed by an inner region which is an oscillating plate; an outer region which surrounds the periphery of the inner region; and a connection portion which connects the inner region with the outer region. Electrodes are formed on two surfaces of the inner region, and a heater and a temperature sensor are disposed to surround the periphery of the electrode on one surface of the inner region where the electrode is formed thereon. The electrodes, the heater and the temperature sensor are respectively connected with terminals on the outer region by leads. A contact area between the temperature sensor and a crystal is increased.

Abstract: A thermostatic-chamber temperature control device includes: a heating element for heating a thermostatic chamber; a bridge circuit having a temperature sensitive element whose resistance value varies in accordance with the temperature of the heating element; a detection circuit for detecting an unbalanced voltage of the bridge circuit; a PWM signal generating circuit for generating a PWM signal corresponding to the unbalanced voltage detected by the detection circuit; and a switching element that has a current output terminal connected to the heating element and a current input terminal connected to a power supply circuit and is driven on the basis of the PWM signal generated by the PWM signal generating circuit.

Abstract: A device includes: a base substrate having a bonding pad and a peripheral pad, the peripheral pad encompassing the bonding pad; an acoustic resonator on the base substrate; a cap substrate having a bonding pad seal and a peripheral pad seal, the bonding pad seal bonding around the perimeter of the bonding pad and the peripheral pad seal bonding with the peripheral pad to define a hermetically sealed volume between the cap substrate and the base substrate, the cap substrate having a through hole therein over the bonding pad providing access for a connection to the bonding pad; a low-resistivity material layer region disposed on a portion of a surface of the cap substrate disposed inside the hermetically sealed volume, the material layer region being isolated from the bonding pad seal; and electronic circuitry disposed in the material layer region and electrical connected with the acoustic resonator.

Abstract: A MEMS resonator comprises a resonator body (34), and an anchor (32) which provides a fixed connection between the resonator body (34) and a support body. A resistive heating element (R1,R2) and a feedback control system are used to maintain the resonator body (34) at a constant temperature. A location for thermally coupling the anchor (32) to the resistive heating element (R1,R2) is selected which has a lowest dependency of its temperature on the ambient temperature during the operation of the feedback control.

Abstract: Methods and apparatus for calibration and temperature compensation of oscillators having mechanical resonators are described. The method(s) may involve measuring the frequency of the oscillator at multiple discrete temperatures and adjusting compensation circuitry of the oscillator at the various temperatures. The compensation circuitry may include multiple programmable elements which may independently adjust the frequency behavior of the oscillator at a respective temperature. Thus, adjustment of the frequency behavior of the oscillator at one temperature may not alter the frequency behavior at a second temperature.

Abstract: The invention discloses a PVT-independent current-controlled oscillator, including a PV-controller, a current-controlled oscillator and a T-controller. The current-controlled oscillator is coupled to the PV-controller and outputs an oscillation frequency.

Abstract: An oven controlled crystal oscillator includes a thermostatic bath, an inner circuit board, an outer circuit board, a heating element, and a temperature sensor. The inner circuit board is positioned inside the thermostatic bath and electrically connected with the outer circuit board via a pin, and the inner circuit board has a crystal oscillation circuit. The outer circuit board has a temperature control circuit and a power supply circuit electrically connecting with the temperature control circuit. The heating element and the temperature sensor electrically connect with the outer circuit board. A though slot is formed through the outer circuit board, and the thermostatic bath is inserted into the though slot.

Abstract: A thermoelectric device transfers heat away from or toward an object using the Peltier effect. In some embodiments, the length of at least one thermoelectric element is at least ten times greater than a combined average cross-sectional dimension, orthogonal to the length, of two thermoelectric elements.

Abstract: The crystal oscillator device includes an air-tight case (1) forming a vacuum chamber (23), a piezoelectric resonator element (11), oscillation circuitry, a temperature sensor, and a heating unit implemented in an integrated-circuit (IC) chip (13) with an active surface (13a). The piezoelectric resonator element (11) and the oscillation circuitry are connected together to form an oscillation circuit. Furthermore, the temperature sensor and the heating unit are enclosed in the vacuum chamber (23) with the piezoelectric resonator element (11). The piezoelectric resonator element is attached in a heat conductive manner to the active surface (13a) of the integrated-circuit chip (13) in such a way that the IC chip provides mechanical support for the piezoelectric resonator element.

Abstract: 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.

Abstract: An oscillator assembly including an oscillator seated on a pad of thermally conductive material formed on the surface of a printed circuit board and covered by a lid defining an oven for the oscillator. In one embodiment, a plurality of heaters are located on different sides of the oscillator and at least partially seated on the pad for evenly transferring heat to the pad and the oscillator. In one embodiment, the oscillator is a temperature compensated crystal oscillator and an integrated amplifier controller circuit on the printed circuit board integrates at least one operational amplifier for controlling the heater(s) and one or more transistors for providing heat to the oven. A canopy seated on the pad and covering the oscillator can be used for transferring heat more evenly to the oscillator. A cavity in the bottom of the printed circuit board defines an insulative air pocket.

Abstract: A MEMS circuit comprises a MEMS device arrangement with temperature dependent output; a resistive heating circuit; and a feedback control system for controlling the resistive heating circuit to provide heating in order to maintain a MEMS device at a constant temperature. The heating is controlled in dependence on the ambient temperature, such that a MEMS device temperature is maintained at one of a plurality of temperatures in dependence on the ambient temperature. This provides power savings because the temperature to which the MEMS device is heated can be kept within a smaller margin of the ambient temperature.

Abstract: The invention relates to an oven controlled crystal oscillator for surface mounting with reduced height (low profile). The oven controlled crystal oscillator for surface mounting comprises: a flat first substrate made of ceramic and on which are installed a crystal device and a heat resistor; and a second substrate made of a glass epoxy resin which is quadrangular in plan view and which faces the first substrate and has a larger external shape in plan view than the first substrate. The second substrate has an opening into whose center the crystal device is inserted, and has terminal sections on four locations corresponding to the surface outer periphery of the first substrate and the peripheral surfaces of the opening in the second substrate, and the terminal sections of the first substrate and second substrate are connected by solder.

Abstract: A constant-temperature type crystal oscillator includes: a crystal unit; an oscillator output circuit; a temperature control circuit; and a circuit substrate, on which circuit elements are installed. A principal surface of the crystal unit is installed so as to face one side board plane of the circuit substrate with interposing a first heat conducting resin, and the heating resistors are installed to be thermally coupled to the crystal unit via a second heat conducting resin. The principal surface of the crystal unit adheres to the one side board plane of the circuit substrate with interposing the first heat conducting resin. The heating resistors are installed on the one side board plane of the circuit substrate so as to sandwich the lead wires including a portion between the pair of lead wires of the crystal unit, and the heating resistors surround an outer circumference of the crystal unit.

Abstract: A voltage reference connects to a voltage-to-current converter to generate a reference current dependent on the reference voltage. Outputs of a toggle-type flip flop connect to switching transistors controlling the reference current charging capacitors. The toggling of the flip-flop is controlled by comparing the capacitor voltages to the reference voltage, such that the toggle frequency is proportional to the time charging the capacitors. Optionally, temperature compensation data, representing a magnitude and direction rotation of the frequency versus temperature characteristic is stored and, based on a sensed temperature, retrieved to modify the reference current.

Abstract: The present invention provides a temperature controlled oscillator capable of detecting the surrounding temperature at a high level of precision, and obtaining stable oscillating frequencies. The temperature controlled oscillator of the invention is provided with a circuit substrate having a crystal resonator, an oscillating circuit, and a temperature control circuit, arranged on one or both principal surfaces, and a container main body that accommodates the circuit substrate and has mount terminals on an outer bottom surface thereof. The temperature control circuit includes at least a first temperature sensor that detects an operating temperature of the crystal resonator, a second temperature sensor that detects a surrounding temperature of the container main body, and a heating resistor that applies heat to the crystal resonator, and lead wires extend from the circuit substrate and are connected electrically to the mount terminals.

Abstract: The crystal oscillator device includes an air-tight case (1) forming a vacuum chamber (23), a piezoelectric resonator element (11), oscillation circuitry, a temperature sensor, and a heating unit implemented in an integrated-circuit (IC) chip (13) with an active surface (13a). The piezoelectric resonator element (11) and the oscillation circuitry are connected together to form an oscillation circuit. Furthermore, the temperature sensor and the heating unit are enclosed in the vacuum chamber (23) with the piezoelectric resonator element (11). The piezoelectric resonator element is attached in a heat conductive manner to the active surface (13a) of the integrated-circuit chip (13) in such a way that the IC chip provides mechanical support for the piezoelectric resonator element.

Abstract: A surface-mount type crystal oscillator has: a container body having a bottom wall and a frame wall having an opening and provided on one principal surface of the bottom wall; a quartz crystal blank hermetically encapsulated in a recess of the container body, which is formed by the opening of the frame wall; and an IC chip on which an oscillating circuit using the crystal blank is integrated. A region which is a region on the one principal surface of the bottom wall and other than formation regions of the frame wall and the recess is made a flat part, and the IC chip is fixed to the one principal surface of the bottom wall by flip-chip bonding, in the flat part. A crystal inspection terminal electrically connected to the crystal blank is provided on a surface of the flat part.

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 oscillator assembly includes a substrate having a top surface, a bottom surface, and a plurality of side surfaces. At least one of the side surfaces has at least one castellation which is covered with conductive material and includes a lower end spaced from the bottom surface of the substrate. The space is defined by an elongate groove in the side surface which is devoid of conductive material and extends between the lower end of the castellation and the bottom surface of the substrate to eliminate the risk of a short circuit with any of the connection pads on a customers motherboard. The oscillator assembly further incorporates an oscillator circuit in which a current limiting resistor is located in series between the power supply and the heater control circuit.

Abstract: A constant-temperature type crystal oscillator includes: a crystal unit; an oscillator output circuit; a temperature control circuit; and a circuit substrate, on which circuit elements are installed. A principal surface of the crystal unit is installed so as to face one side board plane of the circuit substrate with interposing a first heat conducting resin, and the heating resistors are installed to be thermally coupled to the crystal unit via a second heat conducting resin. The principal surface of the crystal unit adheres to the one side board plane of the circuit substrate with interposing the first heat conducting resin. The heating resistors are installed on the one side board plane of the circuit substrate so as to sandwich the lead wires including a portion between the pair of lead wires of the crystal unit, and the heating resistors surround an outer circumference of the crystal unit.

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: An oscillator includes an oscillator circuit and a resonator that produces an output frequency. A temperature compensation circuit is coupled to the oscillator circuit. The temperature compensation circuit stabilizes the output frequency in response to changes in temperature. At least one temperature sensor and a temperature sensor signal modification circuit are coupled to the temperature compensation circuit. The temperature sensor signal modification circuit receives a temperature signal from the temperature sensor and generates a modified temperature sensor signal that is transmitted to the temperature compensation circuit.

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 system is provided for the regulation of temperature of a crystal oscillator, that system having a thermally conductive support disposed upon a substrate and upon which is disposed the crystal oscillator, an array of thermal vias disposed around the crystal oscillator within the substrate, at least one primary heater communicating with the support, a thermal enclosure communicating with the array of thermal vias, and a at least one secondary heater communicating with the enclosure.

Abstract: An oscillator assembly including an oscillator seated on a pad of thermally conductive material formed on the surface of a printed circuit board and covered by a lid defining an oven for the oscillator. In one embodiment, a plurality of heaters are located on different sides of the oscillator and at least partially seated on the pad for evenly transferring heat to the pad and the oscillator. In one embodiment, the oscillator is a temperature compensated crystal oscillator and an integrated amplifier controller circuit on the printed circuit board integrates at least one operational amplifier for controlling the heater(s) and one or more transistors for providing heat to the oven. A canopy seated on the pad and covering the oscillator can be used for transferring heat more evenly to the oscillator. A cavity in the bottom of the printed circuit board defines an insulative air pocket.