JPS6256682B2 - - Google Patents
Info
- Publication number
- JPS6256682B2 JPS6256682B2 JP57097240A JP9724082A JPS6256682B2 JP S6256682 B2 JPS6256682 B2 JP S6256682B2 JP 57097240 A JP57097240 A JP 57097240A JP 9724082 A JP9724082 A JP 9724082A JP S6256682 B2 JPS6256682 B2 JP S6256682B2
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- temperature
- compensation circuit
- power supply
- variable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000013078 crystal Substances 0.000 claims description 13
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 3
- 230000010355 oscillation Effects 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L1/00—Stabilisation of generator output against variations of physical values, e.g. power supply
- H03L1/02—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only
- H03L1/022—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature
- H03L1/023—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature by using voltage variable capacitance diodes
Landscapes
- Oscillators With Electromechanical Resonators (AREA)
Description
【発明の詳細な説明】
本発明は温度補償水晶発振器（以下TCXOと称
する）の温度補償回路の改良に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a temperature compensation circuit for a temperature compensated crystal oscillator (hereinafter referred to as TCXO).
TXCOの温度補償回路は温度補償を行うべき水
晶振動子の温度―周波数特性をキヤンセルすべく
サーミスタ等の温度―抵抗係数が大なる素子を含
む抵抗を巧みに組み合わせ定電圧電源回路から供
給される直流電圧を分圧して電圧制御水晶発振器
（以下VCXOと称する）の可変容量ダイオードに
印加することによつて水晶振動子の負荷容量を温
度に対応して変化させ発振周波数を温度に無関係
に一定ならしめるものである。 TXCO's temperature compensation circuit skillfully combines the temperature of the crystal resonator to be compensated for, the temperature of the thermistor to cancel the frequency characteristics, and a resistor including an element with a large resistance coefficient. By dividing the voltage and applying it to the variable capacitance diode of the voltage controlled crystal oscillator (hereinafter referred to as VCXO), the load capacitance of the crystal resonator changes in accordance with the temperature, making the oscillation frequency constant regardless of the temperature. It is something.
しかしながら水晶振動子の周波数―温度特性は
周知の如く２次或は３次の曲線で示されるように
複雑であり、その上回路部品の温度特性が関与す
る為、温度補償回路の定数算出には極めて大きな
工数を要するという問題があつた。 However, as is well known, the frequency-temperature characteristics of a crystal resonator are complex as shown by quadratic or cubic curves, and the temperature characteristics of the circuit components are also involved, so it is difficult to calculate the constants of the temperature compensation circuit. There was a problem in that it required an extremely large amount of man-hours.
更に水晶振動子の周波数―温度特性には必ずバ
ラツキが存在するので定数の固定している温度補
償回路は汎用性に欠けると共に汎用的に使用すれ
ば周波数の温度による変動を忍ばねばならないと
いう欠陥があつた。 Furthermore, since there are always variations in the frequency-temperature characteristics of a crystal oscillator, a temperature compensation circuit with a fixed constant lacks versatility, and if used for general purposes, it has the disadvantage of having to tolerate fluctuations in frequency due to temperature. It was hot.
本発明は上述の如き従来のTCXOの温度補償回
路の欠陥を完全に除去する為になされたものであ
つて、サーミスタの如き感温素子を含む温度補償
回路を介して定電圧電源から供給される直流を分
圧する分圧抵抗に可変電圧電源を直列に接続し、
更に該電源に並列に該電源の電圧を分圧する一組
の抵抗を接続して前記温度補償回路及び分圧抵抗
を介して分圧した直流の電圧と前記一組の抵抗を
介して分圧した可変電圧電源から供給する直流電
圧との差の電圧を前記温度補償回路が制御すべき
VCXOの可変容量ダイオードに印加するよう構成
すると共に前記温度補償回路の前記分圧抵抗の値
と該抵抗を除いて前記感温素子を含む回路の総合
抵抗の値との比を前記一組の分圧抵抗の抵抗値相
互の比と等しく設定した改良されたTCXOの温度
補償回路を提供することを目的とする。 The present invention has been made to completely eliminate the defects of the conventional temperature compensation circuit of the TCXO as described above, and is supplied from a constant voltage power source via a temperature compensation circuit that includes a temperature sensing element such as a thermistor. A variable voltage power supply is connected in series to a voltage dividing resistor that divides the DC voltage.
Further, a set of resistors for dividing the voltage of the power supply is connected in parallel with the power supply, and the DC voltage is divided through the temperature compensation circuit and the voltage dividing resistor, and the voltage is divided through the set of resistors. The temperature compensation circuit should control the voltage difference from the DC voltage supplied from the variable voltage power supply.
The voltage is applied to the variable capacitance diode of the VCXO, and the ratio of the value of the voltage dividing resistor of the temperature compensation circuit to the value of the total resistance of the circuit including the temperature sensing element excluding the resistor is determined for the set of voltage components. The purpose of the present invention is to provide an improved temperature compensation circuit for a TCXO in which the resistance values of the piezoresistors are set equal to each other.
以下、本発明を実施例を示す図面によつて詳細
に説明する。 Hereinafter, the present invention will be explained in detail with reference to drawings showing embodiments.
第１図は本発明の理解を助ける為に示す従来の
TCXOの概略回路図である。 FIG. 1 is a conventional diagram shown to aid understanding of the present invention.
FIG. 2 is a schematic circuit diagram of a TCXO.
即ち、定電圧電源１によつて電圧を一定値に安
定化した直流を温度補償回路２に供給する。温度
補償回路２は一般に固定抵抗R1，R2及びサーミ
スタR3（Ｔ）並びに分圧抵抗R4等の抵抗素子を
適宜組み合わせ所望の温度―出力電圧特性を実現
する回路である。 That is, direct current whose voltage is stabilized to a constant value by the constant voltage power supply 1 is supplied to the temperature compensation circuit 2 . The temperature compensation circuit 2 is generally a circuit that realizes desired temperature-output voltage characteristics by appropriately combining fixed resistors R 1 , R 2 , thermistor R 3 (T), and resistance elements such as voltage dividing resistor R 4 .
而して前記温度補償回路２の出力をVCXO３に
接続し、該VCXO３を構成する可変容量ダイオー
ドＤに前記分圧抵抗R4によつて分圧された電圧
を印加することによつて水晶振動子４の負荷容量
を変え以つて発振周波数を温度に無関係に一定な
らしむるものである。 By connecting the output of the temperature compensation circuit 2 to the VCXO 3 and applying the voltage divided by the voltage dividing resistor R 4 to the variable capacitance diode D constituting the VCXO 3, the crystal resonator By changing the load capacity of 4, the oscillation frequency is kept constant regardless of temperature.
斯る構成をとる従来のTCXOは本図からも明ら
かな如く前記温度補償回路２を構成する各抵抗の
定数を設定することがCAD（コンピユータを用
いた回路設計）によつても極めて手間がかかる上
前記各定数は全て固定であるからこれに組み込む
前記水晶振動子４の周波数―温度特性にバラツキ
が多い場合には対応し得ず汎用性に欠けたもので
あること前述のとうりである。 As is clear from this figure, in a conventional TCXO with such a configuration, setting the constants of each resistor constituting the temperature compensation circuit 2 is extremely time-consuming even by CAD (computer-aided circuit design). As mentioned above, since all of the above-mentioned constants are fixed, it cannot cope with cases where there are many variations in the frequency-temperature characteristics of the crystal resonator 4 incorporated therein, and thus lacks versatility.
この問題を解決する為、本発明は第２図に示す
如き回路を付加する。 To solve this problem, the present invention adds a circuit as shown in FIG.
即ち、前記温度補償回路の出力電圧を分圧する
分圧抵抗R4に直列に可変電圧電源５を接続し、
これと並列に前記可変電圧を分圧する一組の抵抗
R6及びR7を設ける。 That is, a variable voltage power supply 5 is connected in series with a voltage dividing resistor R4 that divides the output voltage of the temperature compensation circuit,
A set of resistors that divides the variable voltage in parallel with this
Provide R 6 and R 7 .
前記可変電圧は本TCXOの電源から可変抵抗
R8介して得ると共にその分圧電圧を前記一組の
分圧抵抗R6及びR7の接続部から高周波阻止抵抗
R9を介して前記VCXO３の可変容量ダイオードＤ
のアノード側に接続する。 The variable voltage is connected to the variable resistor from the power supply of this TCXO.
The divided voltage is obtained through the high frequency blocking resistor from the connection point of the pair of voltage dividing resistors R6 and R7 .
Variable capacitance diode D of said VCXO3 via R9
Connect to the anode side of the
尚、前記温度補償回路２の出力端と前記ダイオ
ードＤのカソードとの間に設けた抵抗R5は高周
波阻止抵抗であり、前記ダイオードＤのアースと
アノードとの間の容量Ｃは高周波バイパス用コン
デンサである。 Note that the resistor R5 provided between the output terminal of the temperature compensation circuit 2 and the cathode of the diode D is a high frequency blocking resistor, and the capacitance C between the ground and the anode of the diode D is a high frequency bypass capacitor. It is.
以上の如く構成する本発明の温度補償回路に於
いては前記ダイオードＤに第３図に示す如き電圧
が印加されることになる。 In the temperature compensation circuit of the present invention constructed as described above, a voltage as shown in FIG. 3 is applied to the diode D.
即ち、前記定電圧電源１の出力をE1、前記可
変電圧電源５の出力をE2、前記温度補償回路２
の出力電圧をE3、前記分圧抵抗R6及びR7による
分圧電圧をE4とすると前記可変容量ダイオード
Ｄに印加される電圧E5はE3−E4である。 That is, the output of the constant voltage power supply 1 is E 1 , the output of the variable voltage power supply 5 is E 2 , and the temperature compensation circuit 2 is
Let E 3 be the output voltage of , and E 4 be the voltage divided by the voltage dividing resistors R 6 and R 7 , then the voltage E 5 applied to the variable capacitance diode D is E 3 −E 4 .
又、前記温度補償回路２の分圧抵抗R4を除い
た各抵抗素子の総合抵抗をＲ（Ｔ）とした場合Ｒ
（Ｔ），R4，R6及びR7の値が適切に選択されてい
ないとこの回路が補償すべき基準温度に於ける前
記可変容量ダイオードＤに印加される電圧が変化
してしまいはなはだ具合が悪い。 Furthermore, when the total resistance of each resistance element excluding the voltage dividing resistor R4 of the temperature compensation circuit 2 is R(T), R
If the values of (T), R 4 , R 6 and R 7 are not selected properly, the voltage applied to the variable capacitance diode D at the reference temperature to be compensated by this circuit will change dramatically. It's bad.
そこで前記基準温度に於ける前記ダイオードに
印加される電圧E5を前記可変電圧電源電圧E2の
値に無関係に一定としうる条件について検討す
る。 Therefore, conditions under which the voltage E 5 applied to the diode at the reference temperature can be made constant regardless of the value of the variable voltage power supply voltage E 2 will be considered.
第３図に於いてＲ（Ｔ）の基準温度Ｔpに於け
る値をＲ（Ｔp）とすると、
E3−E2＝Ｒ４／Ｒ（Ｔ）＋Ｒ４（E1−E2）
∴E3＝Ｒ４／Ｒ（Ｔｐ）＋Ｒ４（E1−E2）＋E2
＝Ｅ１−Ｅ２／Ｒ（Ｔｐ）／Ｒ４＋１＋E2 ……(1)
ここでＲ（Ｔｐ）／Ｒ４＝α ……(2)
とおくと、
前記(1)式は
E3＝Ｅ１−Ｅ２／α＋１＋E2＝αＥ２＋Ｅ１／α＋１
……(3)
一方、E4＝Ｒ７／Ｒ６＋Ｒ７E2＝Ｒ７／Ｒ６／１＋Ｒ
７／Ｒ６E2……(4)
又、前記ダイオードＤに印加される電圧E5は
E5＝E3−E4＝αＥ２＋Ｅ１／α＋１−Ｒ７／Ｒ６／Ｒ
７／Ｒ６＋１・E2
＝〔α／α＋１−Ｒ７／Ｒ６／Ｒ７／Ｒ６＋１〕E2
＋Ｅ１／α＋１……(5)
前記(5)式からE2を消去する条件は
α／α＋１＝Ｒ７／Ｒ６／Ｒ７／Ｒ６＋１であるから
Ｒ７／Ｒ６＝α＝Ｒ（Ｔｐ）／Ｒ４ ……(6)
即ち、前記温度補償回路２の分圧抵抗R4とこ
れを除いた総合抵抗の基準温度Ｔpに於ける値と
の比Ｒ（Ｔp）／R4と前記可変電圧電源５の一組
の分圧抵抗R6及びR7の比R7／R6との比を等しく
設定しておけば前記可変電圧電源５の電圧E2を
調整しても基準温度Ｔpに於ける前記可変容量ダ
イオードＤに印加される電圧を一定に保つことが
できる。 In Figure 3, if the value of R(T) at the reference temperature T p is R(T p ), then E 3 - E 2 = R 4 /R(T) + R 4 (E 1 - E 2 ) ∴E 3 = R 4 /R (T p ) + R 4 (E 1 - E 2 ) + E 2 = E 1 - E 2 /R (T p )/R 4 +1 + E 2 ...(1) Here, R (T p ) / R 4 = α ... (2) Then, the above equation (1) becomes E 3 = E 1 - E 2 / α + 1 + E 2 = αE 2 + E 1 / α + 1
...(3) On the other hand, E 4 =R 7 /R 6 +R 7 E 2 =R 7 /R 6 /1+R
7 / R6E2 ... (4) Also, the voltage E5 applied to the diode D is E5 = E3 - E4 = αE2 + E1 /α+1- R7 / R6 /R
7 / R6 +1・E2 =[α/α+1− R7 / R6 / R7 / R6 +1] E2
+E 1 /α+1...(5) Since the condition for eliminating E 2 from the above formula (5) is α/α+1=R 7 /R 6 /R 7 /R 6 +1, R 7 /R 6 =α=R (T p )/R 4 ...(6) That is, the ratio of the voltage dividing resistor R 4 of the temperature compensation circuit 2 to the value of the total resistance excluding this at the reference temperature T p R (T p )/ If the ratio R 7 /R 6 of R 4 and a set of voltage dividing resistors R 6 and R 7 of the variable voltage power supply 5 is set equal, the voltage E 2 of the variable voltage power supply 5 can be adjusted. Also, the voltage applied to the variable capacitance diode D at the reference temperature T p can be kept constant.
即ち、第４図に示す如く前記Ｔpに於ける前記
ダイオードＤへの印加電圧を一定に保ちつつ温度
―印加電圧特性を前記水晶振動子４の周波数―温
度特性に合わせ込むことが可能となるものであ
る。 That is, as shown in FIG. 4, it is possible to match the temperature-applied voltage characteristic to the frequency-temperature characteristic of the crystal resonator 4 while keeping the voltage applied to the diode D at T p constant. It is something.
本発明に係るTCXOの温度補償回路は以上説明
した如く構成しかつ機能するので水晶振動子の周
波数―温度特性に関する製造上のバラツキに対し
前記補償回路の各定数を前記バラツキの中心近傍
に合わせて設計し、あとは個々に前記可変電圧電
源を調整して合わせ込めばよいので極めて汎用性
に富むから回路の量産効果を著しく向上しコスト
を低減する効果がある。 Since the temperature compensation circuit of the TCXO according to the present invention is configured and functions as explained above, each constant of the compensation circuit is adjusted to be close to the center of the variation in order to cope with manufacturing variations in the frequency-temperature characteristics of the crystal resonator. After designing, all that is required is to individually adjust and match the variable voltage power supply, which is extremely versatile, and has the effect of significantly improving the mass production effect of the circuit and reducing costs.
又、従来は不可能であつたダイオードに対する
印加電圧の個別微調により前記水晶振動子の特性
のバラツキに起因する発振周波数の精度を向上す
る上でも著しい効果を発揮するるものである。 Further, by individually finely adjusting the voltage applied to the diodes, which has been impossible in the past, the present invention has a remarkable effect in improving the accuracy of the oscillation frequency caused by variations in the characteristics of the crystal resonator.
尚、本発明の温度補償回路は第２図に示した実
施例に限定する必然性は全くなく、可変電圧電源
としてボリウムを用いる他、例えば抵抗値の異な
る抵抗素子を用意し適宜差し換えるようにしても
よいし、回路設計の都合によつては別個の電源に
よつても差しつかえないことは自明である。 It should be noted that the temperature compensation circuit of the present invention is not necessarily limited to the embodiment shown in FIG. 2, and in addition to using a volume as a variable voltage power source, for example, resistive elements with different resistance values may be prepared and replaced as appropriate. It is obvious that a separate power supply may be used depending on the circuit design.
第１図は従来のTCXOの温度補償回路の概略構
成を示す図、第２図は本発明のTCXOの温度補償
回路の一実施例を示す図、第３図は第２図の回路
に於ける各部に加わる電圧の関係を説明する図、
第４図は本発明の温度補償回路によつて得られる
可変容量ダイオードに印加される電圧と温度との
関係を示す図である。
１……定電圧電源、２……温度補償回路、３…
…VCXO、４……水晶振動子、５……可変電圧電
源、R3（Ｔ）……感温素子、R4……分圧抵抗、
R6及びR7……一組の分圧抵抗、Ｄ……可変容量
ダイオード。
Fig. 1 is a diagram showing a schematic configuration of a conventional TCXO temperature compensation circuit, Fig. 2 is a diagram showing an embodiment of the TCXO temperature compensation circuit of the present invention, and Fig. 3 is a diagram showing a schematic configuration of a conventional TCXO temperature compensation circuit. A diagram explaining the relationship between the voltages applied to each part,
FIG. 4 is a diagram showing the relationship between temperature and voltage applied to a variable capacitance diode obtained by the temperature compensation circuit of the present invention. 1... Constant voltage power supply, 2... Temperature compensation circuit, 3...
...VCXO, 4...Crystal resonator, 5...Variable voltage power supply, R3 (T)...Temperature sensing element, R4 ...Voltage dividing resistor,
R6 and R7 ...a set of voltage dividing resistors, D...variable capacitance diode.
Claims (1)
源から供給される直流を分圧する分圧抵抗とを含
む温度補償回路に於いて、前記分圧抵抗に直列に
可変電圧電源を、更に該可変電圧電源に並列にそ
の電圧を分圧する一組の抵抗を接続し、該一組の
抵抗によつて分圧した電圧と前記定電圧電源から
の直流を分圧する分圧抵抗によつて分圧した電圧
との差の電圧を前記温度補償回路が制御すべき
VCXOの可変容量ダイオードに印加すると共に前
記温度補償回路の分圧抵抗の値と該抵抗を除いた
前記感温素子を含む総合抵抗の補償基準温度に於
ける抵抗値との比を前記可変電圧電源に並列に接
続した一組の分圧抵抗相互の抵抗値の比と等しく
設定することによつて、前記可変電圧電源の供給
する直流電圧を変化させても前記ダイオードに印
加する電圧の前記補償温度に於ける値を常に一定
に保ちつつその温度―印加電圧特性を前記VCXO
の水晶振動子の温度―周波数特性に対応して変化
しうるようにしたことを特徴とするTCXOの温度
補償回路。1. In a temperature compensation circuit that includes a temperature sensing element with a large temperature-resistance coefficient and a voltage dividing resistor that divides the DC voltage supplied from a constant voltage power source, a variable voltage power source is connected in series with the voltage dividing resistor, and A set of resistors that divides the voltage is connected in parallel to a variable voltage power supply, and the voltage divided by the set of resistors and the DC voltage from the constant voltage power supply are divided by the voltage dividing resistor. The temperature compensation circuit should control the voltage difference between the
The voltage is applied to the variable capacitance diode of the VCXO, and the ratio between the value of the voltage dividing resistor of the temperature compensation circuit and the resistance value of the total resistance including the temperature sensing element excluding the resistor at the compensation reference temperature is determined by the variable voltage power supply. By setting the voltage equal to the ratio of the resistance values of a pair of voltage dividing resistors connected in parallel to each other, the compensation temperature of the voltage applied to the diode can be maintained even when the DC voltage supplied by the variable voltage power supply is changed. While keeping the value constant, the temperature-applied voltage characteristics are
A TCXO temperature compensation circuit characterized by being able to change according to the temperature-frequency characteristics of the crystal resonator.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9724082A JPS58213508A (en) | 1982-06-07 | 1982-06-07 | Circuit for compensating temperature of tcxo |
| US06/501,126 US4587499A (en) | 1982-06-07 | 1983-06-06 | Temperature compensating circuit for oscillator |
| EP83303295A EP0096587B1 (en) | 1982-06-07 | 1983-06-07 | Temperature compensating circuit for oscillator |
| DE8383303295T DE3376942D1 (en) | 1982-06-07 | 1983-06-07 | Temperature compensating circuit for oscillator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9724082A JPS58213508A (en) | 1982-06-07 | 1982-06-07 | Circuit for compensating temperature of tcxo |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58213508A JPS58213508A (en) | 1983-12-12 |
| JPS6256682B2 true JPS6256682B2 (en) | 1987-11-26 |
Family
ID=14187083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9724082A Granted JPS58213508A (en) | 1982-06-07 | 1982-06-07 | Circuit for compensating temperature of tcxo |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58213508A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5291344A (en) * | 1976-01-26 | 1977-08-01 | Kinsekisha Lab Ltd | Circuit for compensating temperature of crystal oscillator |
-
1982
- 1982-06-07 JP JP9724082A patent/JPS58213508A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5291344A (en) * | 1976-01-26 | 1977-08-01 | Kinsekisha Lab Ltd | Circuit for compensating temperature of crystal oscillator |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58213508A (en) | 1983-12-12 |
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