JP2003046334A - Temperature compensation type crystal oscillator - Google Patents
Temperature compensation type crystal oscillatorInfo
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- JP2003046334A JP2003046334A JP2001228174A JP2001228174A JP2003046334A JP 2003046334 A JP2003046334 A JP 2003046334A JP 2001228174 A JP2001228174 A JP 2001228174A JP 2001228174 A JP2001228174 A JP 2001228174A JP 2003046334 A JP2003046334 A JP 2003046334A
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- temperature
- circuit
- crystal oscillator
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、温度補償型水晶発
振器に関し、特に、低消費電力の温度補償型水晶発振器
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature compensated crystal oscillator, and more particularly to a low power consumption temperature compensated crystal oscillator.
【０００２】[0002]
【従来の技術】従来、携帯電話端末又は基地局の基準周
波数信号源として使用される温度補償型水晶発振器とし
て、図５に示す構成が知られている。図５に示すよう
に、従来例の温度補償型水晶発振器は、温度検出回路１
が水晶発振回路５の周囲温度を検出して周囲温度に対応
する基準電圧を出力し、補償電圧発生回路２が基準電圧
に基づき水晶発振回路５の発振周波数を一定とさせる補
償電圧を抵抗４を介して水晶発振回路５に与え、水晶発
振回路５の発振信号が出力端子６に出力される構成にな
っている。2. Description of the Related Art Conventionally, a structure shown in FIG. 5 is known as a temperature-compensated crystal oscillator used as a reference frequency signal source of a mobile phone terminal or a base station. As shown in FIG. 5, the temperature-compensated crystal oscillator of the conventional example has a temperature detection circuit 1
Detects the ambient temperature of the crystal oscillating circuit 5 and outputs a reference voltage corresponding to the ambient temperature, and the compensating voltage generating circuit 2 applies a compensating voltage for making the oscillation frequency of the crystal oscillating circuit 5 constant based on the reference voltage to the resistor 4. The oscillation signal of the crystal oscillation circuit 5 is supplied to the crystal oscillation circuit 5 through the output terminal 6 and is output.
【０００３】また、水晶発振回路５は、水晶振動子５２
が入力端と出力端との間に接続されたインバータ５１
と、インバータ５１の入力端と低電位側電源ＶＳＳとの
間に接続されたバラクタ５３と、インバータ５１の出力
端と低電位側電源ＶＳＳとの間に接続されたコンデンサ
５４とを備え、バラクタ５３に入力される補償電圧に対
応して発振周波数が変化する構成になっている。Further, the crystal oscillation circuit 5 includes a crystal oscillator 52.
Is connected between the input end and the output end of the inverter 51
A varactor 53 connected between the input end of the inverter 51 and the low potential side power supply VSS, and a capacitor 54 connected between the output end of the inverter 51 and the low potential side power supply VSS. The oscillation frequency changes in accordance with the compensation voltage input to.
【０００４】即ち、水晶振動子５２の共振周波数が温度
特性を有し、水晶発振回路５単体の発振周波数に周波数
偏差が生じるため、電圧制御可変容量素子であるバラク
タ５３の逆バイアス電圧を水晶発振回路５の周囲温度に
基づく補償電圧により可変して、水晶発振回路５の発振
周波数が一定となるように温度補償している。That is, since the resonance frequency of the crystal oscillator 52 has a temperature characteristic and a frequency deviation occurs in the oscillation frequency of the crystal oscillation circuit 5 alone, the reverse bias voltage of the varactor 53, which is a voltage controlled variable capacitance element, is oscillated by the crystal oscillation. The temperature is compensated so that the oscillation frequency of the crystal oscillation circuit 5 is constant by varying the compensation voltage based on the ambient temperature of the circuit 5.
【０００５】[0005]
【発明が解決しようとする課題】しかし、図５に示す従
来例の温度補償型水晶発振器において、補償電圧発生回
路２は通常多段接続された演算増幅器により構成される
が、温度補償型水晶発振器の低消費電力化の目的のため
に、全ての演算増幅器をバイポーラトランジスタによる
構成ではなくＭＯＳトランジスタにより構成すると、図
６に示すように、ＭＯＳトランジスタはバイポーラトラ
ンジスタに比べ雑音電圧レベルが高く、特に低周波領域
の１／ｆ雑音電圧は１００倍程度レベルが高いので、補
償電圧発生回路２から出力される補償電圧には、多段の
演算増幅器により加重平均された高レベルの１／ｆ雑音
電圧が含まれることになり、温度補償型水晶発振器の重
要特性であるＣ／Ｎ（キャリア周波数成分に対するその
他周波数成分の比）特性が悪化してしまうという問題が
発生する。However, in the temperature-compensated crystal oscillator of the conventional example shown in FIG. 5, the compensation voltage generating circuit 2 is usually composed of operational amplifiers connected in multiple stages. If all the operational amplifiers are composed of MOS transistors instead of bipolar transistors for the purpose of reducing power consumption, as shown in FIG. 6, MOS transistors have a higher noise voltage level than bipolar transistors, and particularly low frequency. Since the 1 / f noise voltage in the region is about 100 times higher in level, the compensation voltage output from the compensation voltage generation circuit 2 includes the high level 1 / f noise voltage weighted and averaged by the multistage operational amplifiers. Therefore, C / N (ratio of other frequency component to carrier frequency component), which is an important characteristic of the temperature-compensated crystal oscillator, The problem occurs that the characteristics are deteriorated.
【０００６】また、温度補償の高精度化を図ろうとすれ
ば、演算増幅器のさらなる多段化が必要となって、１／
ｆ雑音が大きな問題となる。Further, if it is attempted to improve the accuracy of temperature compensation, it is necessary to further increase the number of operational amplifier stages.
f noise is a big problem.
【０００７】本発明は、かかる問題点に鑑みてなされた
ものであって、低消費電力であってＣ／Ｎ特性が改善さ
れた温度補償型水晶発振器を提供することを目的とす
る。The present invention has been made in view of the above problems, and an object of the present invention is to provide a temperature-compensated crystal oscillator having low power consumption and improved C / N characteristics.
【０００８】[0008]
【課題を解決するための手段】本発明の温度補償型水晶
発振器は、入力される制御電圧に対応して発振周波数が
変化する水晶発振回路と、前記水晶発振回路の周囲温度
を検出して前記周囲温度に対応する基準電圧を出力する
温度検出回路と、前記基準電圧に基づき前記発振周波数
を一定とさせる補償電圧を出力する補償電圧発生回路
と、前記補償電圧から１／ｆ雑音電圧を除去して前記制
御電圧として出力する雑音除去回路と、を備えることを
特徴とする。A temperature-compensated crystal oscillator according to the present invention detects a crystal oscillation circuit whose oscillation frequency changes according to an input control voltage, and detects the ambient temperature of the crystal oscillation circuit to detect the ambient temperature. A temperature detection circuit that outputs a reference voltage corresponding to the ambient temperature, a compensation voltage generation circuit that outputs a compensation voltage that makes the oscillation frequency constant based on the reference voltage, and a 1 / f noise voltage is removed from the compensation voltage. And a noise removal circuit that outputs the control voltage as the control voltage.
【０００９】また、前記雑音除去回路が、ハイパスフィ
ルタを備えることを特徴とする。Further, the noise removing circuit includes a high-pass filter.
【００１０】また、前記ハイパスフィルタが、スイッチ
トキャパシタ回路により構成されることを特徴とする。The high-pass filter is composed of a switched capacitor circuit.
【００１１】また、前記ハイパスフィルタが、前記制御
電圧を出力する演算増幅器と、一端に固定電位が与えら
れる容量と、第１の接点に前記補償電圧が与えられると
ともに第２の接点が前記演算増幅器の入力端に接続され
て前記容量の他端を前記第１の接点と前記第２の接点と
に交互に切替接続するスイッチ手段と、を備えることを
特徴とする。The high-pass filter outputs the control voltage, an operational amplifier, a capacitor to which a fixed potential is applied to one end, the compensation voltage to a first contact, and a second contact to the operational amplifier. Switch means for connecting the other end of the capacitance to the first contact and the second contact alternately for switching connection.
【００１２】また、前記補償電圧発生回路が、前記基準
電圧に基づき関数電圧を発生して前記補償電圧として出
力する増幅手段を備えることを特徴とする。Further, the compensation voltage generating circuit is provided with an amplifying means for generating a function voltage based on the reference voltage and outputting the function voltage as the compensation voltage.
【００１３】また、前記補償電圧発生回路が、前記基準
電圧に基づき１次関数電圧を出力する第１の増幅手段
と、前記基準電圧に基づき低温側３次関数電圧を出力す
る第２の増幅手段と、前記基準電圧に基づき高温側３次
関数電圧を出力する第３の増幅手段と、前記１次関数電
圧と前記低温側３次関数電圧と前記高温側３次関数電圧
とを加算して前記補償電圧を出力する加算増幅手段と、
を備えることを特徴とする。Further, the compensation voltage generating circuit outputs a first-order function voltage based on the reference voltage, and a second amplification means outputs a low-temperature side third-order function voltage based on the reference voltage. And a third amplifying means for outputting a high temperature side cubic function voltage based on the reference voltage, the first order function voltage, the low temperature side cubic function voltage and the high temperature side cubic function voltage are added to each other. Summing amplification means for outputting a compensation voltage,
It is characterized by including.
【００１４】また、前記補償電圧発生回路が、ＭＯＳト
ランジスタにより構成されることを特徴とする。Further, the compensation voltage generating circuit is constituted by a MOS transistor.
【００１５】[0015]
【発明の実施の形態】次に、本発明の実施の形態を図面
を参照して説明する。図１は、本発明の実施の形態の温
度補償型水晶発振器の構成図である。図１に示すよう
に、本発明の実施の形態の温度補償型水晶発振器は、温
度検出回路１と、補償電圧発生回路２と、雑音除去回路
３と、抵抗４と、水晶発振回路５と、出力端子６と、を
備える。DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a temperature-compensated crystal oscillator according to an embodiment of the present invention. As shown in FIG. 1, a temperature-compensated crystal oscillator according to an embodiment of the present invention includes a temperature detection circuit 1, a compensation voltage generation circuit 2, a noise elimination circuit 3, a resistor 4, a crystal oscillation circuit 5, And an output terminal 6.
【００１６】温度検出回路１が、水晶発振回路５の周囲
温度を検出して水晶発振回路５の周囲温度に対応する基
準電圧１０１を出力する。The temperature detection circuit 1 detects the ambient temperature of the crystal oscillation circuit 5 and outputs a reference voltage 101 corresponding to the ambient temperature of the crystal oscillation circuit 5.
【００１７】補償電圧発生回路２が、基準電圧１０１に
基づき水晶発振回路５の発振周波数を一定とさせる補償
電圧１０２を出力する。The compensating voltage generating circuit 2 outputs a compensating voltage 102 for keeping the oscillation frequency of the crystal oscillating circuit 5 constant based on the reference voltage 101.
【００１８】雑音除去回路３が、補償電圧１０２から１
／ｆ雑音電圧を除去して制御電圧１０３として出力す
る。The noise elimination circuit 3 uses the compensation voltages 102 to 1
The / f noise voltage is removed and output as the control voltage 103.
【００１９】水晶発振回路５が、緩衝用の抵抗４を介し
て入力される制御電圧１０３に対応して発振周波数を変
化させ、出力端子６に発振信号１０４を出力する。The crystal oscillation circuit 5 changes the oscillation frequency according to the control voltage 103 input via the buffering resistor 4 and outputs the oscillation signal 104 to the output terminal 6.
【００２０】雑音除去回路３には、発振信号１０４がク
ロック信号として入力される。The oscillation signal 104 is input to the noise elimination circuit 3 as a clock signal.
【００２１】また、水晶発振回路５は、インバータ５１
と、水晶振動子５２と、電圧制御可変容量素子としての
バラクタ５３と、コンデンサ５４と、を備え、水晶振動
子５２がインバータ５１の入力端とインバータ５１の出
力端との間に接続され、バラクタ５３のカソード端がイ
ンバータ５１の入力端に接続され、バラクタ５３のアノ
ード端が低電位側電源ＶＳＳに接続され、コンデンサ５
４がインバータ５１の出力端と低電位側電源ＶＳＳとの
間に接続され、制御電圧１０３が抵抗４を介してバラク
タ５３のカソード端に与えられ、インバータ５１の出力
端から出力端子６に発振信号１０４が出力される。Further, the crystal oscillator circuit 5 includes an inverter 51.
A crystal oscillator 52, a varactor 53 as a voltage controlled variable capacitance element, and a capacitor 54. The crystal oscillator 52 is connected between the input end of the inverter 51 and the output end of the inverter 51, and the varactor is connected. The cathode end of 53 is connected to the input end of the inverter 51, the anode end of the varactor 53 is connected to the low potential side power supply VSS, and the capacitor 5
4 is connected between the output end of the inverter 51 and the low-potential-side power supply VSS, the control voltage 103 is given to the cathode end of the varactor 53 via the resistor 4, and the oscillation signal is output from the output end of the inverter 51 to the output terminal 6. 104 is output.
【００２２】図２は、温度検出回路１、補償電圧発生回
路２及び雑音除去回路３の構成図である。FIG. 2 is a configuration diagram of the temperature detection circuit 1, the compensation voltage generation circuit 2 and the noise removal circuit 3.
【００２３】温度検出回路１は、ＰＮ接合ダイオード１
１と、定電流源１２と、を備え、高電位側電源ＶＤＤに
接続される定電流源１２により、低電位側電源ＶＳＳに
接続されるＰＮ接合ダイオード１１に順方向電流を流
し、−２ｍＶ／℃の温度特性を有するＰＮ接合ダイオー
ド１１の順方向電圧を基準電圧１０１として出力する。The temperature detecting circuit 1 comprises a PN junction diode 1
1 and a constant current source 12, and a constant current source 12 connected to the high-potential side power supply VDD causes a forward current to flow in the PN junction diode 11 connected to the low-potential side power supply VSS, −2 mV / The forward voltage of the PN junction diode 11 having a temperature characteristic of ° C is output as the reference voltage 101.
【００２４】補償電圧発生回路２は、第１の増幅手段と
しての１次関数電圧生成増幅器２１と、第２の増幅手段
としての低温側３次関数電流生成増幅器２２及び電流電
圧変換増幅器２３と、第３の増幅手段としての高温側３
次関数電流生成増幅器２４及び電流電圧変換増幅器２５
と、加算増幅器２６と、を備え、１次関数電圧生成増幅
器２１が基準電圧１０１に基づき１次関数電圧を出力
し、低温側３次関数電流生成増幅器２２が基準電圧１０
１に基づき低温側３次関数電流を出力し、電流電圧変換
増幅器２３が低温側３次関数電流を低温側３次関数電圧
に変換出力し、高温側３次関数電流生成増幅器２４が基
準電圧１０１に基づき高温側３次関数電流を出力し、電
流電圧変換増幅器２５が高温側３次関数電流を高温側３
次関数電圧に変換出力し、加算増幅器２６が１次関数電
圧、低温側３次関数電圧及び高温側３次関数電圧を加算
して補償電圧１０２を出力する。The compensating voltage generating circuit 2 includes a linear function voltage generating amplifier 21 as a first amplifying means, a low temperature side cubic function current generating amplifier 22 and a current-voltage converting amplifier 23 as a second amplifying means, High temperature side 3 as third amplifying means
Next-function current generation amplifier 24 and current-voltage conversion amplifier 25
And a summing amplifier 26, the linear function voltage generation amplifier 21 outputs a linear function voltage based on the reference voltage 101, and the low temperature side tertiary function current generation amplifier 22 outputs the reference voltage 10
Based on 1, the low temperature side cubic function current is output, the current-voltage conversion amplifier 23 converts the low temperature side cubic function current into the low temperature side cubic function voltage, and the high temperature side cubic function current generation amplifier 24 outputs the reference voltage 101. A high temperature side cubic function current is output based on the above, and the current-voltage conversion amplifier 25 outputs the high temperature side cubic function current to the high temperature side 3.
The summing amplifier 26 adds the linear function voltage, the low temperature side cubic function voltage and the high temperature side cubic function voltage, and outputs the compensation voltage 102.
【００２５】また、１次関数電圧生成増幅器２１と、低
温側３次関数電流生成増幅器２２及び電流電圧変換増幅
器２３と、高温側３次関数電流生成増幅器２４及び電流
電圧変換増幅器２５と、加算増幅器２６と、がＭＯＳト
ランジスタにより構成される。Further, the linear function voltage generation amplifier 21, the low temperature side cubic function current generation amplifier 22 and the current voltage conversion amplifier 23, the high temperature side cubic function current generation amplifier 24 and the current voltage conversion amplifier 25, and the summing amplifier. 26 is composed of a MOS transistor.
【００２６】雑音除去回路３は、スイッチ３１と、コン
デンサ３２と、演算増幅器３３と、を備え、ボルテージ
フォロワ接続される演算増幅器３３が制御電圧１０３を
出力し、容量素子としてのコンデンサ３２の一端に固定
電位としての低電位側電源ＶＳＳ電圧が与えられ、スイ
ッチ３１の第１の接点に補償電圧１０２が与えられ、ス
イッチ３１の第２の接点が演算増幅器３３の入力端に接
続されて、スイッチ３１がクロック信号である発振信号
１０４により制御され、発振信号１０４の周波数にした
がいコンデンサ３２の他端がスイッチ３１の第１の接点
とスイッチ３１の第２の接点とに交互に切替接続され、
スイッチトキャパシタ回路によるハイパスフィルタが構
成される。The noise elimination circuit 3 includes a switch 31, a capacitor 32, and an operational amplifier 33. The operational amplifier 33 connected to the voltage follower outputs the control voltage 103, and one end of the capacitor 32 as a capacitive element is output. The low-potential-side power supply VSS voltage as a fixed potential is applied, the compensating voltage 102 is applied to the first contact of the switch 31, and the second contact of the switch 31 is connected to the input terminal of the operational amplifier 33. Is controlled by the oscillation signal 104 which is a clock signal, and the other end of the capacitor 32 is alternately switched and connected to the first contact of the switch 31 and the second contact of the switch 31 according to the frequency of the oscillation signal 104.
A high pass filter is formed by a switched capacitor circuit.
【００２７】スイッチ３１は、ＭＯＳトランジスタによ
るアナログスイッチにより構成される。The switch 31 is composed of an analog switch using MOS transistors.
【００２８】雑音除去回路３は、補償電圧１０２の直流
成分を通過させ、交流成分である１／ｆ雑音電圧を除去
する。The noise removing circuit 3 passes the DC component of the compensation voltage 102 and removes the 1 / f noise voltage which is the AC component.
【００２９】次に動作を説明する。図３は、本発明の実
施の形態の温度補償型水晶発振器の動作説明図である。
図３（ａ）は、水晶発振回路５単体の発振周波数の周波
数偏差の温度特性図であり、結晶軸がＣカットで切り出
された水晶振動子５２の共振周波数の温度特性が−２５
℃から８５℃程度において逆Ｓ字状を示すため、水晶発
振回路５単体も同様に、低温側において発振周波数が中
心値より高くなり、高温側において発振周波数が中心値
より低くなる逆Ｓ字状の周波数偏差を有する。Next, the operation will be described. FIG. 3 is an operation explanatory diagram of the temperature-compensated crystal oscillator according to the embodiment of the present invention.
FIG. 3A is a temperature characteristic diagram of the frequency deviation of the oscillation frequency of the single crystal oscillation circuit 5, and the temperature characteristic of the resonance frequency of the crystal oscillator 52 whose crystal axis is cut out by C cut is −25.
Since it exhibits an inverted S-shape at about 85 ° C to 85 ° C, the crystal oscillation circuit 5 itself also has an inverted S-shape in which the oscillation frequency is higher than the center value on the low temperature side and lower than the center value on the high temperature side. Has a frequency deviation of.
【００３０】図３（ｂ）は、補償電圧１０２の温度特性
図であり、補償電圧発生回路２は、水晶発振回路５の周
囲温度に対応する１次関数電圧、低温側３次関数電圧及
び高温側３次関数電圧を加算して、水晶発振回路５単体
の発振周波数の周波数偏差の温度特性を打ち消すように
設定されたＳ字状の補償電圧１０２を出力する。FIG. 3B is a temperature characteristic diagram of the compensation voltage 102. The compensation voltage generation circuit 2 has a linear function voltage corresponding to the ambient temperature of the crystal oscillation circuit 5, a low temperature side cubic function voltage and a high temperature. The side cubic function voltage is added to output the S-shaped compensation voltage 102 set so as to cancel the temperature characteristic of the frequency deviation of the oscillation frequency of the single crystal oscillation circuit 5.
【００３１】図３（ｃ）は、バラクタ５３の容量の逆バ
イアス電圧特性図であり、図３（ｄ）は、水晶発振回路
５の発振周波数のバラクタ５３の容量に対する特性図で
あり、逆バイアス電圧が高くなるほど発振周波数が高く
なる。FIG. 3C is a reverse bias voltage characteristic diagram of the capacitance of the varactor 53, and FIG. 3D is a characteristic diagram of the oscillation frequency of the crystal oscillation circuit 5 with respect to the capacitance of the varactor 53. The higher the voltage, the higher the oscillation frequency.
【００３２】以上の結果、図３（ｅ）に示すように、水
晶発振回路５の発振周波数が、水晶発振回路５の周囲温
度には依存せず一定となり、周波数偏差が平坦化され、
温度補償がなされる。As a result, as shown in FIG. 3 (e), the oscillation frequency of the crystal oscillation circuit 5 becomes constant independent of the ambient temperature of the crystal oscillation circuit 5, and the frequency deviation is flattened.
Temperature compensation is done.
【００３３】図４は、雑音除去回路３の電圧利得の周波
数特性図であり、ボルテージフォロワであるため電圧利
得が０ｄＢであるが、スイッチ３１が発振信号１０４の
周波数で切替動作を行うため、発振信号１０４の周波数
がハイパスフィルタとしての低域カットオフ周波数ｆＬ
となり、補償電圧１０２に含まれる低域カットオフ周波
数ｆＬ以下の１／ｆ雑音電圧が除去される。FIG. 4 is a frequency characteristic diagram of the voltage gain of the noise elimination circuit 3. The voltage gain is 0 dB because it is a voltage follower, but the switch 31 performs the switching operation at the frequency of the oscillation signal 104, so that the oscillation is generated. The frequency of the signal 104 is the low cutoff frequency fL as a high-pass filter.
Therefore, the 1 / f noise voltage equal to or lower than the low cutoff frequency fL included in the compensation voltage 102 is removed.
【００３４】例えば、水晶発振回路５の発振信号１０４
の周波数を２０ＭＨｚとすれば、１００Ｈｚ付近の１／
ｆ雑音電圧が−４０ｄＢ程度に減衰され十分に除去され
る。For example, the oscillation signal 104 of the crystal oscillation circuit 5
If the frequency of is 20 MHz, then 1/100 Hz
The f noise voltage is attenuated to about -40 dB and is sufficiently removed.
【００３５】以上説明したように、本発明の実施の形態
の温度補償型水晶発振器の構成によれば、雑音除去回路
３を備えることにより、補償電圧発生回路２が出力する
補償電圧１０２から１／ｆ雑音電圧を除去して水晶発振
回路５に供給することができるので、低消費電力化のた
めＭＯＳトランジスタ構成による補償電圧発生回路２を
備える温度補償型水晶発振器であっても、Ｃ／Ｎ特性を
改善することができる。As described above, according to the structure of the temperature-compensated crystal oscillator of the embodiment of the present invention, by providing the noise elimination circuit 3, the compensation voltage 102 output from the compensation voltage generation circuit 2 is reduced to 1 / Since the f noise voltage can be removed and supplied to the crystal oscillation circuit 5, even the temperature-compensated crystal oscillator including the compensation voltage generation circuit 2 having a MOS transistor configuration for low power consumption has a C / N characteristic. Can be improved.
【００３６】なお、本発明の実施の形態の温度補償型水
晶発振器において、雑音除去回路３の電圧利得をボルテ
ージフォロワによる０ｄＢとしたが、補償電圧発生回路
２の加算増幅器２６の利得を調整して任意の利得に変更
することができる。In the temperature-compensated crystal oscillator according to the embodiment of the present invention, the voltage gain of the noise elimination circuit 3 is set to 0 dB by the voltage follower, but the gain of the summing amplifier 26 of the compensation voltage generation circuit 2 is adjusted. It can be changed to any gain.
【００３７】さらに、雑音除去回路３のスイッチ３１の
切替制御を発振信号１０４により行っているが、別にク
ロック信号源を備えて切替制御を行うように変更するこ
とができる。Further, although the switching control of the switch 31 of the noise elimination circuit 3 is performed by the oscillation signal 104, it can be changed so that a separate clock signal source is provided and the switching control is performed.
【００３８】[0038]
【発明の効果】本発明による効果は、低消費電力であっ
てＣ／Ｎ特性が改善された温度補償型水晶発振器を実現
できることである。The effect of the present invention is to realize a temperature-compensated crystal oscillator with low power consumption and improved C / N characteristics.
【図１】本発明の実施の形態の温度補償型水晶発振器の
構成図である。FIG. 1 is a configuration diagram of a temperature-compensated crystal oscillator according to an embodiment of the present invention.
【図２】温度検出回路１、補償電圧発生回路２及び雑音
除去回路３の構成図である。FIG. 2 is a configuration diagram of a temperature detection circuit 1, a compensation voltage generation circuit 2, and a noise removal circuit 3.
【図３】本発明の実施の形態の温度補償型水晶発振器の
動作説明図である。FIG. 3 is an operation explanatory diagram of the temperature-compensated crystal oscillator according to the embodiment of the present invention.
【図４】雑音除去回路３の特性図である。FIG. 4 is a characteristic diagram of the noise removal circuit 3.
【図５】従来例の温度補償型水晶発振器の構成図であ
る。FIG. 5 is a block diagram of a conventional temperature-compensated crystal oscillator.
【図６】補償電圧に含まれる雑音の説明図である。FIG. 6 is an explanatory diagram of noise included in a compensation voltage.
１ 温度検出回路 １１ ＰＮ接合ダイオード １２ 定電流源 ２ 補償電圧発生回路 ２１ １次関数電圧生成増幅器 ２２ 低温側３次関数電流生成増幅器 ２３ 電流電圧変換増幅器 ２４ 高温側３次関数電流生成増幅器 ２５ 電流電圧変換増幅器 ２６ 加算増幅器 ３ 雑音除去回路 ３１ スイッチ ３２ コンデンサ ３３ 演算増幅器 ４ 抵抗 ５ 水晶発振回路 ５１ インバータ ５２ 水晶振動子 ５３ バラクタ ５４ コンデンサ ６ 出力端子 1 Temperature detection circuit 11 PN junction diode 12 constant current source 2 Compensation voltage generator 21 Linear Function Voltage Generation Amplifier 22 Low-temperature side cubic function current generation amplifier 23 Current-voltage conversion amplifier 24 High temperature side cubic function current generation amplifier 25 Current-voltage conversion amplifier 26 Summing amplifier 3 Noise elimination circuit 31 switch 32 capacitors 33 operational amplifier 4 resistance 5 Crystal oscillator circuit 51 inverter 52 Crystal unit 53 Varactor 54 capacitor 6 output terminals
フロントページの続き Ｆターム(参考） 5J079 AA04 BA02 BA12 BA39 CB01 DA12 DB01 FA13 FA14 FA21 FB00 FB01 FB03 FB11 FB28 FB48 GA04 GA09 Continued front page F-term (reference) 5J079 AA04 BA02 BA12 BA39 CB01 DA12 DB01 FA13 FA14 FA21 FB00 FB01 FB03 FB11 FB28 FB48 GA04 GA09
Claims (7)
数が変化する水晶発振回路と、前記水晶発振回路の周囲
温度を検出して前記周囲温度に対応する基準電圧を出力
する温度検出回路と、前記基準電圧に基づき前記発振周
波数を一定とさせる補償電圧を出力する補償電圧発生回
路と、前記補償電圧から１／ｆ雑音電圧を除去して前記
制御電圧として出力する雑音除去回路と、を備えること
を特徴とする温度補償型水晶発振器。1. A crystal oscillating circuit whose oscillation frequency changes in response to an input control voltage, and a temperature detecting circuit which detects an ambient temperature of the crystal oscillating circuit and outputs a reference voltage corresponding to the ambient temperature. A compensation voltage generation circuit that outputs a compensation voltage that makes the oscillation frequency constant based on the reference voltage, and a noise removal circuit that removes a 1 / f noise voltage from the compensation voltage and outputs the noise as the control voltage. A temperature-compensated crystal oscillator characterized by the following.
を備えることを特徴とする請求項１記載の温度補償型水
晶発振器。2. The temperature-compensated crystal oscillator according to claim 1, wherein the noise elimination circuit includes a high-pass filter.
ャパシタ回路により構成されることを特徴とする請求項
２記載の温度補償型水晶発振器。3. The temperature-compensated crystal oscillator according to claim 2, wherein the high-pass filter is composed of a switched capacitor circuit.
を出力する演算増幅器と、一端に固定電位が与えられる
容量と、第１の接点に前記補償電圧が与えられるととも
に第２の接点が前記演算増幅器の入力端に接続されて前
記容量の他端を前記第１の接点と前記第２の接点とに交
互に切替接続するスイッチ手段と、を備えることを特徴
とする請求項２記載の温度補償型水晶発振器。4. The high-pass filter includes an operational amplifier that outputs the control voltage, a capacitor to which a fixed potential is applied to one end, a compensation voltage to a first contact, and a second contact to the operational amplifier. 3. The temperature-compensated type according to claim 2, further comprising switch means connected to an input end of the switch and switchingly connecting the other end of the capacitance to the first contact and the second contact alternately. Crystal oscillator.
に基づき関数電圧を発生して前記補償電圧として出力す
る増幅手段を備えることを特徴とする請求項１記載の温
度補償型水晶発振器。5. The temperature-compensated crystal oscillator according to claim 1, wherein the compensation voltage generating circuit includes an amplifying unit that generates a function voltage based on the reference voltage and outputs the function voltage as the compensation voltage.
に基づき１次関数電圧を出力する第１の増幅手段と、前
記基準電圧に基づき低温側３次関数電圧を出力する第２
の増幅手段と、前記基準電圧に基づき高温側３次関数電
圧を出力する第３の増幅手段と、前記１次関数電圧と前
記低温側３次関数電圧と前記高温側３次関数電圧とを加
算して前記補償電圧を出力する加算増幅手段と、を備え
ることを特徴とする請求項１記載の温度補償型水晶発振
器。6. The compensating voltage generating circuit outputs first-order function voltage based on the reference voltage, and second amplifying means outputs low-temperature side third-order function voltage based on the reference voltage.
Amplifying means, third amplifying means for outputting a high temperature side cubic function voltage based on the reference voltage, the primary function voltage, the low temperature side cubic function voltage and the high temperature side cubic function voltage are added. The temperature-compensated crystal oscillator according to claim 1, further comprising: an addition amplification unit that outputs the compensation voltage.
ジスタにより構成されることを特徴とする請求項１記載
の温度補償型水晶発振器。7. The temperature-compensated crystal oscillator according to claim 1, wherein the compensation voltage generation circuit is composed of a MOS transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001228174A JP2003046334A (en) | 2001-07-27 | 2001-07-27 | Temperature compensation type crystal oscillator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001228174A JP2003046334A (en) | 2001-07-27 | 2001-07-27 | Temperature compensation type crystal oscillator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003046334A true JP2003046334A (en) | 2003-02-14 |
Family
ID=19060720
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001228174A Pending JP2003046334A (en) | 2001-07-27 | 2001-07-27 | Temperature compensation type crystal oscillator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003046334A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004079895A1 (en) * | 2003-03-06 | 2004-09-16 | Matsushita Electric Industrial Co. Ltd. | Quartz oscillation circuit |
| US7268636B2 (en) | 2004-07-14 | 2007-09-11 | Matsushita Electric Industrial Co., Ltd. | Voltage controlled oscillator |
| JP2009273087A (en) * | 2008-05-12 | 2009-11-19 | Epson Toyocom Corp | Piezoelectric oscillator |
| KR101622929B1 (en) | 2008-03-17 | 2016-05-20 | 세이코 엔피시 가부시키가이샤 | Oscillation circuit |
| CN109687865A (en) * | 2018-12-02 | 2019-04-26 | 南京中电熊猫晶体科技有限公司 | A kind of big pressure controlled constant tempeature crystal oscillator of small size |
-
2001
- 2001-07-27 JP JP2001228174A patent/JP2003046334A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004079895A1 (en) * | 2003-03-06 | 2004-09-16 | Matsushita Electric Industrial Co. Ltd. | Quartz oscillation circuit |
| US7268636B2 (en) | 2004-07-14 | 2007-09-11 | Matsushita Electric Industrial Co., Ltd. | Voltage controlled oscillator |
| KR101622929B1 (en) | 2008-03-17 | 2016-05-20 | 세이코 엔피시 가부시키가이샤 | Oscillation circuit |
| JP2009273087A (en) * | 2008-05-12 | 2009-11-19 | Epson Toyocom Corp | Piezoelectric oscillator |
| CN109687865A (en) * | 2018-12-02 | 2019-04-26 | 南京中电熊猫晶体科技有限公司 | A kind of big pressure controlled constant tempeature crystal oscillator of small size |
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