Nihon Dempa Kogyo Co., Ltd.

Dsp Technology Associates, Inc.

Kazuo Akaike

Tsukasa Kobata

Kaoru Kobayashi

Nobuo Tsukamoto

Junichiro Yamakawa

Shinichi Sato

Hiroshi Hoshigami

Mikio Takano

Yasushi Yamamoto

Kozo Ono

Mitsuaki Koyama

Tomoya Yorita

Tsuyoshi Shiobara

Susumu Yoshimoto

Toshimasa Tsuda

Tatsunori Onzuka

Takashi Nakaoka

Takayuki Ishikawa

Takaaki Ishii

Hiroyuki Kukita

Akihiro Nakamura

Takeru Mutoh

Shigenori Watanabe

Minoru Fukuda

Tsutomu Yamakawa

Shigetaka Kaga

Kenji Kawahata

Kietsu Saito

Mohd Hafidz Bin Ahmad Adlan

Yuichiro Arai

Naoto Inouchi

Masazumi Kubota

Makoto Okamoto

A PLL device includes a voltage control oscillation unit, an analog/digital converter, a quadrature demodulation unit, a comparison signal output unit, a phase difference detection unit, a loop filter, and a digital/analog converter. The quadrature demodulation unit quadrature-demodulates the digital feedback signal to obtain an in-phase component (I component) and a quadrature-phase component (Q component). The comparison signal has a set frequency of the output signal when the feedback signal is the output signal and has a frequency obtained by dividing the set frequency by the dividing number when the feedback signal is the frequency division signal. The phase difference detection unit obtains a phase difference between the digital feedback signal and the digital comparison signal based on the I component and the Q component of the digital feedback signal and the I component and an Q component of a comparison signal.

PLL device

An crystal resonator includes a first oscillating circuit that oscillates a crystal resonator at a first frequency, a first impedance adjusting circuit that adjusts an impedance of a first oscillating system including the crystal resonator and the first oscillating circuit, a second oscillating circuit that oscillates the crystal resonator at a second frequency that is different from the first frequency, a second impedance adjusting circuit that adjusts an impedance of a second oscillating system including the crystal resonator and the second oscillating circuit, and a controlling circuit that controls the first impedance adjusting circuit and the second impedance adjusting circuit.

Crystal oscillator and method of manufacturing crystal oscillators

An oscillator detects a temperature of an atmosphere where a crystal resonator for an oscillation output is placed using a temperature detector to stabilize the temperature by controlling a temperature of a heater based on a temperature detection value. The device includes a buffer amplifier interposed in a signal path of a control signal generated based on the temperature detection value, a heater disposed such that a collector and an emitter position between a power source unit and a ground and constituted of a transistor having a base connected to an output port of the buffer amplifier, and a first differential amplifier disposed to adjust a gain of the buffer amplifier to cancel voltage fluctuation of the power source unit and amplifying a difference between a voltage corresponding to the supply voltage and a preliminarily set voltage to input to a gain adjustment port of the buffer amplifier.

Oscillator for detecting temperature of atmosphere

A surface mount device in which a pin adapter that is integrally formed with a plurality of pins connects a base board and a main board is provided to enable an automatic mounting, to enable a reflow soldering, to increase the flexibility of design, and to satisfy requirements of customers. In the surface mount device, a pin adapterthat is formed integrally with a plurality of pinsis placed on a base board, the base boardand the main boardare connected by inserting the tips of the pinsinto the corresponding locations of the main board, the leg portions of the pin adapterare folded toward inside, and opening sectionsare formed at the leg portions.

Surface mount device

An oscillation device corrects a setting value of an output frequency based on a detection result of an ambient temperature of a crystal unit. The oscillation device includes: an oscillation circuit; a temperature detection portion that detects the ambient temperature and outputs a digital value corresponding to the temperature detection value; an accumulator that accumulates the digital value; a rounding processing portion that performs rounding for the digital value accumulated in the accumulator; a digital filter that receives the digital value obtained from the rounding processing portion and obtains a step response gradually increasing from '0' and converging to a step value; and a correction value obtaining portion that obtains a frequency correction value of the oscillation frequency of the oscillation circuit caused by a difference between the ambient temperature and a reference temperature, wherein the setting value of the output frequency is corrected based on the frequency correction value.

Oscillation device

An oscillator configured to obtain a frequency output corresponding to a frequency setting value includes: an oscillation circuit portion that receives the frequency setting value; a setting value output portion that outputs a digital value for designating the frequency setting value; an interpolation circuit portion that performs interpolation for a digital value of lower-order bits out of the digital value output from the setting value output portion; and an adder that adds an output of the interpolation circuit portion and a digital value of higher-order bits out of the digital value output from the setting value output portion, wherein a signal output from the interpolation circuit portion is sequential data having first and second values different from each other, and output counts of the first and second values are determined based on a ratio corresponding to the digital value of the lower-order bits.

Oscillator

A crystal controlled oscillator of the present disclosure includes: an oscillator circuit for oscillator output, a first oscillator circuit, a second oscillator circuit, a heating unit, a pulse generator, a frequency difference detector, an addition unit, a circuit unit, a frequency measuring unit, a determination unit, and a signal selector. The signal selector is configured to: select a control signal where electric power supplied to the heating unit is smaller than supplied electric power in the detection range in a case where a frequency in a set period at the train of pulses is out of the detection range at the high temperature side; select a control signal where electric power supplied to the heating unit becomes a preset value in a case where a frequency in the set period at the train of pulses is out of the detection range at the low temperature side.

Crystal controlled oscillator and oscillating device

A crystal oscillator includes: an oscillation circuit; first and second oscillation circuits connected to first and second temperature detection crystal units, respectively; a heating portion configured to constantly maintain an ambient temperature; a frequency difference detection portion that obtains, as a temperature detection value, '{(f&#x2212;f)/f}&#x2212;{(f&#x2212;f)/f}', where 'f' and &#x201c;f&#x201d; denote oscillation frequencies of the first and second oscillation circuits, respectively, and &#x201c;f&#x201d; and &#x201c;f&#x201d; denote oscillation frequencies of the first and second oscillation circuits, respectively, at a reference temperature; an accumulator that accumulates the temperature detection value; a rounding processing portion that performs rounding for the temperature detection value accumulated in the accumulator depending on a rounding factor designated independently from the accumulation number; and a heating control portion that controls power supplied to the heating portion based on the temperature detection value subjected to the rounding in the rounding processing portion.

Piece-crystal oscillator and oscillation device

An oscillation device is provided. The oscillation device includes: a main circuit portion, a heating unit, first and second crystal units, first and second oscillator circuits, a frequency difference detector, a first addition unit, an integration circuit unit, a circuit unit configured to control an electric power to be supplied to the heating unit, a compensation value obtaining unit, and a second addition unit. The compensation value obtaining unit is configured to obtain a frequency compensation value for compensating an output frequency of the main circuit portion based on an integrated value output from the integration circuit unit, and based on a change in the clock signal due to a difference between the temperature of the atmosphere and the temperature setting value of the heating unit. The second addition unit is configured to add the frequency compensation value to a frequency setting value.

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 fand f, and oscillation frequencies of the oscillation outputs at a reference temperature are set to fand, respectively, {(f&#x2212;f)/f}&#x2212;{(f&#x2212;f)/f} 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.

Quartz-crystal controlled oscillator

An oscillator includes a nominal frequency output unit, a frequency adjustment amount output unit, a gain output unit, a multiplier, and an adder. The nominal frequency output unit is configured to output a first digital value corresponding to the nominal frequency. The frequency adjustment amount output unit is configured to output a second digital value corresponding to a rate of frequency in order to set a frequency adjustment amount with respect to the nominal frequency using the rate of frequency. The gain output unit is configured to output a third digital value corresponding to a gain to be multiplied by the second digital value. The multiplier is configured to multiply the second digital value by the third digital value, thus outputting a fourth digital value. The adder adds the first digital value and the fourth digital value to output the added result as a setting signal of frequency.

Oscillator with frequency adjustment

In forming a frequency synthesizer by using PLL using processing of digital signals, an A/D converting unit is not required. By the integration of a digital value that depends on a set frequency, a saw-tooth wave serving as a phase signal is generated. A frequency signal output from a voltage-controlled oscillator is input via a frequency divider to an edge detecting unit, which then detects a rising edge or a falling edge of the frequency signal to generate a rectangular-wave signal that depends on a frequency of the frequency signal. Then, a latched circuit latches a value of the saw-tooth wave in response to the rectangular-wave signal, and this value is integrated in a loop filter and the resultant is used as a control voltage of the voltage-controlled oscillator.

Frequency synthesizer

There is provided a frequency synthesizer capable of improving phase noise. A sinusoidal signal with a frequency set by a frequency setting part is output as a digital signal from a set signal output part, and the digital signal is D/A-converted. A difference between a sinusoidal signal with a frequency corresponding to an output frequency of a voltage controlled oscillating part and a sinusoidal signal output from a D/A converting part is amplified by a differential amplifier, and an amplified signal is input via an A/D converting part to a means for extracting a phase difference between the aforesaid sinusoidal signals. A voltage corresponding to a signal being the result of integration of the phase difference is input as a control voltage to the voltage controlled oscillating part. Then, a gain of the differential amplifier is set larger than a maximum value of phase noise degradation of the A/D converting part, whereby the phase noise degradation of the A/D converting part is cancelled.

An oscillation device capable of highly accurate temperature compensation of an output frequency is provided. The oscillation device includes: first and second oscillator circuits oscillating first and second quartz-crystal resonators with overtones respectively; a frequency difference detecting part finding a value corresponding to a difference value between values corresponding to differences between fand fand between fand f, where fand fare oscillation frequencies of the first and second oscillator circuits, and fand fare oscillation frequencies of the first and second oscillator circuits at a reference temperature; and a correction value obtaining part which, based on the value corresponding to the difference value and a relation between the value corresponding to the difference value and a frequency correction value of the oscillation frequency fobtains the frequency correction value of fwherein the output frequency is corrected based on the found frequency correction value.

To perform, in an oscillation device compensating an output frequency based on a detection result of ambient temperature, temperature compensation of the output frequency with high accuracy. First and second quartz-crystal oscillators are structured by using a common quartz-crystal piece, and when oscillation outputs of first and second oscillation circuits respectively connected to these quartz-crystal oscillators are set to f, f, and oscillation frequencies of the first and the second oscillation circuits at a reference temperature are set to f, f, respectively, a frequency difference being a difference between a value corresponding to a difference between fand fand a value corresponding to a difference between fand fis treated as a temperature at that time. Further, based on the frequency difference, a frequency compensation value is determined through polynomial approximation.

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Sayama, Japan

Kazuo Akaike