JP2693959B2 - Local oscillation circuit - Google Patents
Local oscillation circuitInfo
- Publication number
- JP2693959B2 JP2693959B2 JP63026856A JP2685688A JP2693959B2 JP 2693959 B2 JP2693959 B2 JP 2693959B2 JP 63026856 A JP63026856 A JP 63026856A JP 2685688 A JP2685688 A JP 2685688A JP 2693959 B2 JP2693959 B2 JP 2693959B2
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- local oscillation
- variable capacitance
- capacitance diode
- fine tuning
- 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 - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
- H03J7/00—Automatic frequency control; Automatic scanning over a band of frequencies
- H03J7/02—Automatic frequency control
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
- H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
- H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
- H03B5/1231—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device the amplifier comprising one or more bipolar transistors
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
- H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
- H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
- H03B5/1203—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device the amplifier being a single transistor
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
- H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
- H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
- H03B5/1237—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator
- H03B5/124—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising a voltage dependent capacitance
- H03B5/1243—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising a voltage dependent capacitance the means comprising voltage variable capacitance diodes
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B2200/00—Indexing scheme relating to details of oscillators covered by H03B
- H03B2200/003—Circuit elements of oscillators
- H03B2200/004—Circuit elements of oscillators including a variable capacitance, e.g. a varicap, a varactor or a variable capacitance of a diode or transistor
- H03B2200/0042—Circuit elements of oscillators including a variable capacitance, e.g. a varicap, a varactor or a variable capacitance of a diode or transistor the capacitance diode being in the feedback path
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B2201/00—Aspects of oscillators relating to varying the frequency of the oscillations
- H03B2201/02—Varying the frequency of the oscillations by electronic means
- H03B2201/0208—Varying the frequency of the oscillations by electronic means the means being an element with a variable capacitance, e.g. capacitance diode
Description
【発明の詳細な説明】 「産業上の利用分野」 この発明は電子同調チューナに係り、特にAFT（自動
周波数調整）回路を備えた局部発振回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic tuning tuner, and more particularly to a local oscillation circuit having an AFT (automatic frequency adjustment) circuit.
「従来の技術」 第４図は従来の局部発振回路の回路図である。この局
部発振回路は、増幅回路１と帰還回路２と共振回路３と
AFT回路４とからなる。"Prior Art" FIG. 4 is a circuit diagram of a conventional local oscillation circuit. This local oscillator circuit includes an amplifier circuit 1, a feedback circuit 2, a resonance circuit 3, and
It consists of an AFT circuit 4.
まず、増幅回路１の構成を説明する。Tr1は発振用ト
ランジスタであり、電源電圧Vccからバイアス抵抗R4、R
5、R6、R7を介して直流バイアスが加えられる。コンデ
ンサC6は接地コンデンサであり、交流動作時にトランジ
スタTr1のベース端子を等価的に接地せしめるものであ
る。トランジスタTr1のエミッタ端子はコンデンサC4を
介して出力端子21に接続される。また、出力端子21に
は、一端が接地されたコンデンサC7が負荷として接続さ
れる。そして、この増幅回路１の入力側（トランジスタ
Tr1のコレクタ端子）は、共振用インダクタンスL1を介
して後述する共振回路３と結合されており、このインダ
クタンスL1の両端に発生する信号を増幅して、出力端子
21に出力する。First, the configuration of the amplifier circuit 1 will be described. Tr 1 is an oscillating transistor, and the bias resistors R 4 and R
DC bias is applied via 5 , R 6 and R 7 . The capacitor C 6 is a grounding capacitor and equivalently grounds the base terminal of the transistor Tr 1 during AC operation. The emitter terminal of the transistor Tr 1 is connected to the output terminal 21 via the capacitor C 4 . Further, the output terminal 21 is connected as a load with a capacitor C 7 whose one end is grounded. Then, the input side of the amplifier circuit 1 (transistor
The collector terminal of tr 1) via the resonant inductance L 1 is coupled to the resonance circuit 3 to be described later, it amplifies the signal generated at both ends of the inductance L 1, the output terminal
Output to 21.
次に、帰還回路２の構成を説明する。増幅回路１の出
力端子21には帰還用可変容量ダイオードD2のアノードが
接続されている。そして、この可変容量ダイオードD2の
アノードは抵抗R8を介して接地され、また、カソードは
共振回路３の節点ａに接続される。この結果、出力端子
21に出力される増幅回路１の出力信号は可変容量ダイオ
ードD2を介して共振回路３の節点ａに帰還される。Next, the configuration of the feedback circuit 2 will be described. The anode of the feedback variable capacitance diode D 2 is connected to the output terminal 21 of the amplifier circuit 1. The anode of the variable capacitance diode D 2 is grounded via the resistor R 8 , and the cathode is connected to the node a of the resonance circuit 3. As a result, the output terminal
The output signal of the amplifier circuit 1 output to 21 is fed back to the node a of the resonance circuit 3 via the variable capacitance diode D 2 .
次に、共振回路３の構成を説明する。共振回路３は前
述の通り増幅回路１の入力側に接続され、構成される。
すなわち、節点ａには共振用可変容量ダイオードD3のカ
ソードとコンデンサC3の一端が接続され、可変容量ダイ
オードD3のアノードには一端が接地されたコンデンサC2
および抵抗R3の他端が接続され、コンデンサC3の他端は
インダクタンスL1とコンデンサC5とを直列に介して接地
される。そして、共振回路３は前述の通りインダクタン
スL1により増幅回路１と結合される。また、この共振回
路３の節点ａは抵抗R2を介して局発周波数制御端子11に
接続されている。従って、可変容量ダイオードD3は、抵
抗R2、R3を介して、この局発周波数制御端子11の局発周
波数制御電圧ＶTUによる直流バイアスを受け、容量値が
制御される。この結果、この局発周波数が制御され、こ
の局部発振回路が使用されているチューナにおける選局
が行われる。Next, the configuration of the resonance circuit 3 will be described. The resonance circuit 3 is connected to the input side of the amplifier circuit 1 and configured as described above.
That is, the cathode of the resonant variable capacitance diode D 3 and one end of the capacitor C 3 are connected to the node a, and the anode of the variable capacitance diode D 3 has one end grounded to the capacitor C 2
And the other end of the resistor R 3 are connected, and the other end of the capacitor C 3 is grounded via the inductance L 1 and the capacitor C 5 in series. Then, the resonance circuit 3 is coupled to the amplifier circuit 1 by the inductance L 1 as described above. The node a of the resonance circuit 3 is connected to the local oscillation frequency control terminal 11 via the resistor R 2 . Thus, the variable capacitance diode D 3 is connected via a resistor R 2, R 3, receives DC bias due to local oscillator frequency control voltage VTU the local oscillation frequency control terminal 11, the capacitance value is controlled. As a result, the local oscillation frequency is controlled, and the tuner in which the local oscillation circuit is used is selected.
ところで、前述した帰還回路２の可変容量ダイオード
D2もカソードが共振回路３の節点ａに接続されているの
で、抵抗R2、R8を介して、局発周波数制御電圧ＶTUによ
る直流バイアスを受け、容量値が制御される。すなわ
ち、可変容量ダイオードD2とD3とは、同一の局発周波数
制御電圧ＶTUによって容量値が制御される。このように
する事で、バンドの全域に渡って帰還量がより均一にな
り発振を安定化させる事が可能となる。By the way, the variable capacitance diode of the feedback circuit 2 described above.
Since the cathode of D 2 is also connected to the node a of the resonance circuit 3, the capacitance value is controlled by receiving the DC bias by the local oscillation frequency control voltage VTU via the resistors R 2 and R 8 . That is, the capacitance values of the variable capacitance diodes D 2 and D 3 are controlled by the same local oscillation frequency control voltage VTU. By doing so, the feedback amount becomes more uniform over the entire band, and the oscillation can be stabilized.
次に、AFT回路４の構成を説明する。AFT回路４は共振
回路３と並列に接続され、構成される。すなわち、節点
ａにはコンデンサC1の一端が接続され、コンデンサC1の
他端には、アノードが接地された微同調用可変容量ダイ
オードD1のカソードが接続され、さらに抵抗R1を介して
微同調制御端子12に接続される。ここで、可変容量ダイ
オードD1は、カソードに抵抗R1を介して、微同調制御端
子12の自動微同調電圧ＶAFTを受け、容量値が制御され
る。Next, the configuration of the AFT circuit 4 will be described. The AFT circuit 4 is connected and configured in parallel with the resonance circuit 3. That is, one end of the capacitor C 1 is connected to the node a, the other end of the capacitor C 1 is connected to the cathode of the fine tuning variable capacitance diode D 1 whose anode is grounded, and further through the resistor R 1. It is connected to the fine tuning control terminal 12. Here, the variable capacitance diode D 1 receives the automatic fine tuning voltage VAFT of the fine tuning control terminal 12 via the resistor R 1 at the cathode, and the capacitance value is controlled.
以上要約すると、この局部発振回路はコルピッツ型発
振回路の共振回路３に並列するAFT回路４が接続された
構成になっている。In summary, this local oscillator circuit has a configuration in which an AFT circuit 4 in parallel with the resonant circuit 3 of the Colpitts type oscillator circuit is connected.
次に、この局部発振回路の動作を説明する。第５図
は、第４図の局部発振回路における直流バイアス用抵抗
および直流阻止用コンデンサを省略して、発振動作時の
等価回路を表したものである。この回路において、コン
デンサCf1は第４図の帰還用可変容量コンデンサD2に対
応し、コンデンサCf2は第４図のコンデンサC7に対応
し、コンデンサＣTUは第４図の共振用可変容量ダイオー
ドD3に対応し、コンデンサＣAFTは第４図の微同調用可
変容量ダイオードD1に対応し、インダクタンスL1は第４
図の共振用インダクタンスL1に対応する。この等価回路
図によれば、この局部発振回路の局発周波数ｆは次式で
表される。Next, the operation of this local oscillator circuit will be described. FIG. 5 shows an equivalent circuit at the time of oscillating operation by omitting the DC bias resistor and the DC blocking capacitor in the local oscillation circuit of FIG. In this circuit, the capacitor Cf 1 corresponds to the feedback variable capacitor D 2 of FIG. 4, the capacitor Cf 2 corresponds to the capacitor C 7 of FIG. 4, and the capacitor CTU is the resonant variable diode of FIG. Corresponding to D 3 , the capacitor CAFT corresponds to the fine tuning variable capacitance diode D 1 in FIG. 4, and the inductance L 1 corresponds to the fourth.
This corresponds to the resonance inductance L 1 in the figure. According to this equivalent circuit diagram, the local oscillation frequency f of this local oscillator circuit is expressed by the following equation.
この局部発振回路は上式（１）の局発周波数ｆで発振
し、その発振出力は出力端子21を介して後続の混合器に
供給される。混合器ではチューナの入力信号周波数と局
発周波数との差が検出され、これが規定値になるように
第４図の局部発振回路の微同調制御端子12に自動微同調
制御電圧ＶAFTが送られ、局発周波数の自動微調整が行
われる。 This local oscillation circuit oscillates at the local oscillation frequency f of the above formula (1), and its oscillation output is supplied to the subsequent mixer via the output terminal 21. In the mixer, the difference between the input signal frequency of the tuner and the local oscillation frequency is detected, and the automatic fine tuning control voltage VAFT is sent to the fine tuning control terminal 12 of the local oscillation circuit of FIG. Automatic fine adjustment of the local oscillation frequency is performed.
「発明が解決しようとする課題」 ところで、従来の局部発振回路では共振用可変容量ダ
イオードと並列に微同調用可変容量ダイオードが接続さ
れているため、共振用可変容量ダイオードの容量値が小
さい場合、すなわち発振周波数が高い場合には、微同調
用可変容量ダイオードの容量値変化が発振周波数に及ぼ
す影響が大き過ぎ、逆に、同調用可変容量ダイオードの
容量値が大きい場合、すなわち発振周波数が低い場合に
は、微同調用可変容量ダイオードの容量値変化が発振周
波数に及ぼす影響が小さ過ぎる。従って、この局部発振
回路のバンド内において、高域と低域とで、自動微同調
電圧に対する局発周波数の変位量に大きな周波数偏差が
生じてしまうという問題があった。[Problems to be Solved by the Invention] By the way, in the conventional local oscillation circuit, since the fine tuning variable capacitance diode is connected in parallel with the resonance variable capacitance diode, when the capacitance value of the resonance variable capacitance diode is small, That is, when the oscillation frequency is high, the influence of the capacitance value change of the fine tuning variable capacitance diode on the oscillation frequency is too great, and conversely, when the capacitance value of the tuning variable capacitance diode is large, that is, when the oscillation frequency is low. Therefore, the influence of the capacitance value change of the fine tuning variable capacitance diode on the oscillation frequency is too small. Therefore, there is a problem that a large frequency deviation occurs in the amount of displacement of the local oscillation frequency with respect to the automatic fine tuning voltage in the high band and the low band within the band of the local oscillation circuit.
この発明は上述した事情に鑑みてなされたもので、自
動微同調電圧に対する局発周波数の変位量の偏差が小さ
い局部発振回路を提供することを目的としている。The present invention has been made in view of the above circumstances, and an object thereof is to provide a local oscillation circuit in which the deviation of the displacement amount of the local oscillation frequency from the automatic fine tuning voltage is small.
「課題を解決するための手段」 この発明は、 （ａ）局発周波数制御電圧を与えられて電極間容量が制
御される共振用可変容量ダイオードを有する共振回路
と、 （ｂ）前記共振回路の出力信号を増幅する増幅回路と、 （ｃ）前記局発周波数制御電圧によって電極間容量が制
御され、前記増幅回路の出力信号を前記同調回路に帰還
する帰還用可変容量ダイオードと、 （ｄ）前記増幅回路の出力端と接地間に介挿されて、前
記局発周波数制御電圧に対して独立な自動微同調電圧を
与えられて電極間容量が制御される微同調用可変容量ダ
イオードと、 を具備する事を特徴としている。"Means for Solving the Problem" The present invention provides: (a) a resonance circuit having a resonance variable capacitance diode in which a local oscillation frequency control voltage is applied to control the inter-electrode capacitance; and (b) the resonance circuit. An amplifier circuit for amplifying an output signal; (c) a variable capacitance diode for feedback, in which an interelectrode capacitance is controlled by the local oscillation frequency control voltage, and an output signal of the amplifier circuit is fed back to the tuning circuit; A fine tuning variable capacitance diode which is inserted between the output terminal of the amplifier circuit and the ground, and is provided with an automatic fine tuning voltage independent of the local oscillation frequency control voltage to control the interelectrode capacitance. It is characterized by doing.
「作用」 上記構成によれば、微同調用可変容量ダイオードが帰
還用可変容量ダイオードの容量値に略比例して共振用可
変容量ダイオードに結合され、局発周波数を決定せしめ
る。しかも、この時の帰還用可変容量ダイオードの容量
値は、共振用可変容量ダイオードの容量値に連動して制
御される。従って、微同調用可変容量ダイオードは、共
振用可変容量ダイオードの容量値に略比例した割合で共
振用可変容量ダイオードに結合される。[Operation] According to the above configuration, the fine tuning variable capacitance diode is coupled to the resonance variable capacitance diode substantially in proportion to the capacitance value of the feedback variable capacitance diode to determine the local oscillation frequency. Moreover, the capacitance value of the feedback variable capacitance diode at this time is controlled in association with the capacitance value of the resonance variable capacitance diode. Therefore, the fine tuning variable capacitance diode is coupled to the resonance variable capacitance diode at a rate substantially proportional to the capacitance value of the resonance variable capacitance diode.
「実施例」 以下、図面を参照して本発明の一実施例について説明
する。Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
第１図はこの発明の一実施例による局部発振器の回路
図である。この局部発振回路は、第４図に示す従来の局
部発振回路においてAFT回路４が共振回路３に並列に接
続されていたのに対し、AFT回路４が増幅回路１の出力
端子21に接続されている点のみが異なる。FIG. 1 is a circuit diagram of a local oscillator according to an embodiment of the present invention. In this local oscillator circuit, the AFT circuit 4 is connected in parallel to the resonance circuit 3 in the conventional local oscillator circuit shown in FIG. 4, whereas the AFT circuit 4 is connected to the output terminal 21 of the amplifier circuit 1. The only difference is that
次に、この局部発振回路の動作を説明する。第２図
は、第１図の局部発振回路における直流バイアス用抵抗
および直流阻止用コンデンサを省略して、発振動作時の
等価回路を表したものである。この回路において、コン
デンサCf1、コンデンサCf2、コンデンサＣTU、コンデン
サＣAFT、インダクタンスL1は前述した第５図と同じも
のである。この等価回路図によれば、この局部発振回路
の局発周波数ｆは次式で表される。Next, the operation of this local oscillator circuit will be described. FIG. 2 shows an equivalent circuit at the time of oscillating operation by omitting the DC bias resistor and the DC blocking capacitor in the local oscillation circuit of FIG. In this circuit, the capacitor Cf 1 , the capacitor Cf 2 , the capacitor CTU, the capacitor CAFT, and the inductance L 1 are the same as those in FIG. 5 described above. According to this equivalent circuit diagram, the local oscillation frequency f of this local oscillator circuit is expressed by the following equation.
式（２）により、微同調用可変容量ダイオードD1の容
量値ＣAFTが△ＣAFTだけ変化したとすると、その局発周
波数ｆへの影響は帰還用可変容量ダイオードD2の容量値
Cf1の値に応じて制御される事がわかる。 Assuming that the capacitance value CAFT of the fine tuning variable capacitance diode D 1 is changed by ΔCAFT from the formula (2), the influence on the local oscillation frequency f is the capacitance value of the feedback variable capacitance diode D 2 .
It can be seen that it is controlled according to the value of Cf 1 .
第３図は、第１図に示すこの発明の一実施例による局
部発振回路と第４図に示す従来の局部発振回路とで、微
同調制御電圧ＶAFTに対する微同調周波数変位量△ｆを
示したものである。この図より、本発明の局部発振回路
の方が全バンド内において微同調制御電圧ＶAFTに対す
る微同調周波数変位量△ｆが安定している事がわかる。FIG. 3 shows the fine tuning frequency displacement amount Δf with respect to the fine tuning control voltage VAFT in the local oscillation circuit according to the embodiment of the present invention shown in FIG. 1 and the conventional local oscillation circuit shown in FIG. It is a thing. From this figure, it is understood that the local oscillation circuit of the present invention is more stable in the fine tuning frequency displacement amount Δf with respect to the fine tuning control voltage VAFT in all bands.
「発明の効果」 以上説明したように、この発明によれば、微同調用可
変容量ダイオードは、共振用可変容量ダイオードに連動
して容量値が制御される帰還用可変容量ダイオードを介
して共振用可変容量ダイオードに結合されるため、その
結合度は共振用可変容量ダイオードの容量値に略比例し
たものとなる。従って、局発周波数全域において自動微
同調電圧に対する局発周波数変位量を安定化する事がで
きる効果がある。[Advantages of the Invention] As described above, according to the present invention, the fine tuning variable capacitance diode is used for resonance via the feedback variable capacitance diode whose capacitance value is controlled in association with the resonance variable capacitance diode. Since it is coupled to the variable capacitance diode, the degree of coupling is approximately proportional to the capacitance value of the resonant variable capacitance diode. Therefore, there is an effect that the local oscillation frequency displacement amount with respect to the automatic fine tuning voltage can be stabilized over the entire local oscillation frequency.
第１図はこの発明の一実施例による局部発振回路の構成
図、第２図は同実施例の局部発振回路の発振時の等価回
路図、第３図はこの発明の一実施例による局部発振回路
および従来の局部発振回路における自動微同調電圧に対
する局発周波数の変化を示す図、第４図は従来の局部発
振回路の構成図、第５図は従来の局部発振回路の発振時
の等価回路図である。 D1……微同調用可変容量ダイオード、D2……帰還用可変
容量ダイオード、D3……共振用可変容量ダイオード。FIG. 1 is a block diagram of a local oscillator circuit according to an embodiment of the present invention, FIG. 2 is an equivalent circuit diagram of the local oscillator circuit of the same embodiment during oscillation, and FIG. 3 is a local oscillator according to an embodiment of the present invention. Circuit and conventional local oscillator circuit showing changes in local oscillation frequency with respect to automatic fine tuning voltage, FIG. 4 is a block diagram of a conventional local oscillator circuit, and FIG. 5 is an equivalent circuit of the conventional local oscillator circuit during oscillation. It is a figure. D 1 …… Variable capacitance diode for fine tuning, D 2 …… Variable capacitance diode for feedback, D 3 …… Variable capacitance diode for resonance.
Claims (1)
極間容量が制御される共振用可変容量ダイオードを有す
る共振回路と、 （ｂ）前記共振回路の出力信号を増幅する増幅回路と、 （ｃ）前記局発周波数制御電圧によって電極間容量が制
御され、前記増幅回路の出力信号を前記共振回路に帰還
する帰還用可変容量ダイオードと、 （ｄ）前記増幅回路の出力端と接地間に介挿されて、前
記局発周波数制御電圧に対して独立な自動微同調電圧を
与えられて電極間容量が制御される微同調用可変容量ダ
イオードと、 を具備する事を特徴とする局部発振回路。1. A resonance circuit having a variable capacitance diode for resonance in which a capacitance between electrodes is controlled by being supplied with a local oscillation frequency control voltage, and (b) an amplification circuit for amplifying an output signal of the resonance circuit. , (C) a variable capacitance diode for feedback whose capacitance between electrodes is controlled by the local oscillation frequency control voltage and which feeds back an output signal of the amplifier circuit to the resonance circuit, (d) between an output end of the amplifier circuit and ground A fine tuning variable-capacitance diode, which is inserted into the fine tuning diode to control the inter-electrode capacitance by applying an automatic fine tuning voltage independent of the local oscillation frequency control voltage. circuit.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63026856A JP2693959B2 (en) | 1988-02-08 | 1988-02-08 | Local oscillation circuit |
| KR1019880013292A KR910001649B1 (en) | 1988-02-08 | 1988-10-12 | Local oscillator |
| GB8902366A GB2223903B (en) | 1988-02-08 | 1989-02-03 | Local oscillating circuits |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63026856A JP2693959B2 (en) | 1988-02-08 | 1988-02-08 | Local oscillation circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01202013A JPH01202013A (en) | 1989-08-15 |
| JP2693959B2 true JP2693959B2 (en) | 1997-12-24 |
Family
ID=12204919
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63026856A Expired - Fee Related JP2693959B2 (en) | 1988-02-08 | 1988-02-08 | Local oscillation circuit |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP2693959B2 (en) |
| KR (1) | KR910001649B1 (en) |
| GB (1) | GB2223903B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004530360A (en) * | 2001-04-11 | 2004-09-30 | キョウセラ ワイヤレス コーポレイション | Tunable multiplexer |
| US6801097B2 (en) * | 2002-07-18 | 2004-10-05 | Qualcomm Incorporated | Wideband VCO resonant circuit method and apparatus |
| JP5027472B2 (en) * | 2005-11-09 | 2012-09-19 | ルネサスエレクトロニクス株式会社 | Oscillator and information device using the same |
| DE102006009467A1 (en) | 2006-03-01 | 2007-09-06 | Rohde & Schwarz Gmbh & Co. Kg | Oscillator with entrained amplifier |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4846251A (en) * | 1971-10-14 | 1973-07-02 | ||
| JPS5895419A (en) * | 1981-12-01 | 1983-06-07 | Matsushita Electric Ind Co Ltd | Electronic tuning tuner |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61151415U (en) * | 1985-03-12 | 1986-09-19 |
-
1988
- 1988-02-08 JP JP63026856A patent/JP2693959B2/en not_active Expired - Fee Related
- 1988-10-12 KR KR1019880013292A patent/KR910001649B1/en not_active IP Right Cessation
-
1989
- 1989-02-03 GB GB8902366A patent/GB2223903B/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4846251A (en) * | 1971-10-14 | 1973-07-02 | ||
| JPS5895419A (en) * | 1981-12-01 | 1983-06-07 | Matsushita Electric Ind Co Ltd | Electronic tuning tuner |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2223903A (en) | 1990-04-18 |
| KR910001649B1 (en) | 1991-03-16 |
| GB8902366D0 (en) | 1989-03-22 |
| JPH01202013A (en) | 1989-08-15 |
| KR890013885A (en) | 1989-09-26 |
| GB2223903B (en) | 1992-01-08 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |