KR20000018545U - Single transistor type vco - Google Patents
Single transistor type vco Download PDFInfo
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- KR20000018545U KR20000018545U KR2019990004585U KR19990004585U KR20000018545U KR 20000018545 U KR20000018545 U KR 20000018545U KR 2019990004585 U KR2019990004585 U KR 2019990004585U KR 19990004585 U KR19990004585 U KR 19990004585U KR 20000018545 U KR20000018545 U KR 20000018545U
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- 230000010355 oscillation Effects 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 2
- 230000002238 attenuated effect Effects 0.000 abstract 1
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- 239000003990 capacitor Substances 0.000 description 1
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Classifications
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- 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
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- 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
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/099—Details of the phase-locked loop concerning mainly the controlled oscillator of the loop
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- 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
- H03B2202/00—Aspects of oscillators relating to reduction of undesired oscillations
- H03B2202/02—Reduction of undesired oscillations originated from natural noise of the circuit elements of the oscillator
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- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
Abstract
본 고안은 PLL회로에서 입력전원에 의해 공진주파수가 결정되어 다수의 상이한 주파수를 발생하는 VCO, 특히, 트랜지스터가 단일형이고 출력단의 LPF가 이단인 트랜지스터 단일형 VCO에 관한 것으로서, 본 고안에 의한 트랜지스터 단일형 VCO에 의하면, 하나의 트랜지스터만 사용하고 이에 따라 발생되는 2차 하모닉 성분을 오차 로패스필터를 사용하여 감쇠시키는 구성이므로 기존의 트랜지스터 두 개를 사용할 때와 비교할 때 동일한 출력특성을 얻으면서 부품단가를 줄이수 있고, 회로를 단순화 할 수 있다는 뛰어난 효과가 있다.The present invention relates to a VCO in which a resonant frequency is determined by an input power source in a PLL circuit to generate a plurality of different frequencies, in particular, a transistor single type VCO in which the transistor is a single type and the LPF of the output stage is two-stage. According to the present invention, since only one transistor is used and the second harmonic component generated by the transistor is attenuated using an error low pass filter, the component cost can be reduced while obtaining the same output characteristics as compared with two conventional transistors. There is an excellent effect that the circuit can be simplified.
Description
본 고안은 PLL회로에서 입력전원에 의해 공진주파수가 결정되어 다수의 상이한 주파수를 발생하는 VCO에 관한 것으로, 특히, 트랜지스터가 단일형이고 출력단의 LPF가 이단인 트랜지스터 단일형 VCO에 관한 것이다.The present invention relates to a VCO in which a resonant frequency is determined by an input power source in a PLL circuit to generate a plurality of different frequencies. More particularly, the present invention relates to a transistor single VCO in which a transistor is a single type and a LPF at the output stage is two-stage.
일반적인 PLL(PHASE LOCKED OSCILLATOR, 이하 PLL이라 명명함)회로는 도 1에 도시한 바와같이 주파수제어신호를 입력받는 동시에 후술되는 VCO(VOLTAGE CONTROLLED OSCILLATOR, 이하 VCO라 명명함; 300)로부터 피드백되는 주파수신호를 입력받아 위상이 고정된 주파수 튜닝전압을 출력하는 PLL IC(100)와, 상기 PLL IC(100)에서 주파수 튜닝전압을 입력받아 AC성분을 제거하는 루프필터(LOOP FILTER; 200)와, 상기 루프필터(200)에서 주파수 튜닝전압을 입력받아 결정된 공진 주파수신호를 발생하는 VCO(300)로 구성되어 있다.A general PLL (PHASE LOCKED OSCILLATOR, hereinafter referred to as PLL) circuit receives a frequency control signal as shown in FIG. A PLL IC (100) for receiving a phase-locked frequency tuning voltage, a loop filter (LOOP FILTER) 200 for removing an AC component by receiving a frequency tuning voltage from the PLL IC 100, and the loop The VCO 300 is configured to receive the frequency tuning voltage from the filter 200 and generate a determined resonant frequency signal.
상기 VCO(300)는 상기 루프필터(200)에서 입력받은 주파수 튜닝전압에 의해 커패시턴스가 가변되어 공진주파수를 결정하도록 가변콘덴서(VC1,VC2), L1 및 C1으로 구성된 주파수 결정부(310)와, 상기 주파수 결정부(310)에 의해 결정된 공진주파수를 발생하며 상기 PLL IC(100)로 피트백 주파수를 출력하는 TR2와, 상기 주파수 결정부(310)에 의해 결정된 공진주파수를 발생하며, 출력단으로 공진주파수를 출력하는 TR1과, 상기 TR1에서 발생되는 공진주파수에서 노이즈성분을 제거하도록 상기 TR1의 컬렉터단에 접속되는 발진주파수 정류부(320)와, 상기 TR1의 컬렉터단을 통해 출력되는 공진주파수에서 고주파성분을 제거하도록 상기 TR1의 컬렉터단에 대해 서로 병렬접속된 L3 및 C3로 구성된 LPF(350)로 구성되어 있었다.The VCO 300 includes a frequency determining unit 310 including variable capacitors VC1 and VC2, L1 and C1 so that the capacitance is varied by the frequency tuning voltage input from the loop filter 200 to determine the resonance frequency. Generates a resonance frequency determined by the frequency determiner 310 and outputs a pitback frequency to the PLL IC 100, and generates a resonance frequency determined by the frequency determiner 310 and resonates to an output terminal. A high frequency component at a resonant frequency output through a TR1 outputting a frequency, an oscillation frequency rectifying unit 320 connected to a collector end of the TR1 to remove a noise component from the resonant frequency generated by the TR1, and a collector end of the TR1 LPF 350 composed of L3 and C3 connected in parallel with each other to the collector end of TR1 to remove the current.
이에 대해, 본출원인은 상기 종래 VCO의 구조에 있어서, 두 개의 트랜지스터를 한 개의 트랜지스터로 구성하면서 동일한 출력특성을 구현하기 위한 방안을 모색하여 부품단가를 줄이며 회로구성을 단순화하려고 하였다.On the other hand, the present applicant has attempted to reduce the unit cost and simplify the circuit configuration by finding a method for realizing the same output characteristics while configuring two transistors in the structure of the conventional VCO.
따라서, 본 고안은 상기와 같은 방안에 착안하여 이루어진 것으로서, 본 고안의 목적은 동일한 출력특성을 얻으면서 부품단가를 줄이는 동시에 회로를 단순화 할 수 있는 트랜지스터 단일형 VCO를 제공하는 데 있다.Accordingly, the present invention has been made in view of the above-described schemes, and an object of the present invention is to provide a single transistor VCO capable of simplifying a circuit while reducing component cost while obtaining the same output characteristics.
상기와 같은 목적을 달성하기 위해 본 고안의 트랜지스터 단일형 VCO는 PLL IC에서 출력되는 주파수 튜닝전압에 의해 결정된 공진주파수신호를 발생하는 VCO에 있어서, 상기 주파수 튜닝전압을 입력받아 공진주파수를 결정하는 주파수 결정부와, 상기 주파수 결정부에 의해 공진주파수가 결정되어 이에 상응하는 공진주파수신호를 발생하여 증폭시키는 동시에 상기 PLL IC로 그 공진주파수신호를 피드백시키는 트랜지스터와, 상기 트랜지스터에서 발생되는 노이즈를 제거하도록 상기 트랜지스터의 컬렉터단에 접속되는 발진주파수 정류부와, 상기 트랜지스터에서 공진주파수신호를 입력받아 이단으로 고주파성분 특히 2차하모닉 성분을 제거하는 오차 로패스필터를 구비한 것을 특징으로 한다.In order to achieve the above object, the single transistor VCO of the present invention is a VCO for generating a resonant frequency signal determined by a frequency tuning voltage output from a PLL IC. The frequency determination voltage is determined by receiving the frequency tuning voltage. A resonant frequency determined by the frequency determiner to generate and amplify a corresponding resonant frequency signal, and to feed back the resonant frequency signal to the PLL IC, and to remove noise generated from the transistor. An oscillation frequency rectifying unit connected to the collector stage of the transistor, and an error low pass filter for receiving a resonant frequency signal from the transistor and removing a high frequency component, in particular, a second harmonic component, in two stages.
도 1은 종래기술에 의한 두 개의 트랜지스터가 구비된 VCO가 적용된 PLL회로도,1 is a PLL circuit diagram to which a VCO with two transistors according to the prior art is applied.
도 2는 본 고안의 일실시예에 의한 트랜지스터 단일형 VCO가 적용된 PLL회로도,2 is a PLL circuit diagram to which a single transistor VCO is applied according to an embodiment of the present invention;
도 3은 종래 두 개의 트랜지스터를 사용하는 VCO의 출력단에서 측정한 노이즈특성과 본 고안의 일실시예에 의한 트랜지스터 단일형 VCO의 출력단에서 측정한 노이즈특성비교표.3 is a noise characteristic measured at the output terminal of the conventional VCO using two transistors and noise characteristics measured at the output terminal of the transistor-type VCO according to an embodiment of the present invention.
＜도면의 주요부분에 대한 부호의 설명＞<Description of the code | symbol about the principal part of drawing>
100 : PLL IC 200 : 루프필터100: PLL IC 200: loop filter
3000 : VCO 3100 : 주파수 결정부3000: VCO 3100: Frequency Determination Unit
3200 : 노이즈제거부 3500 : 오차 로패스필터3200: noise canceller 3500: error low pass filter
이하, 본 고안의 실시예에 의한 트랜지스터 단일형 VCO에 대해 첨부된 도면을 참조하여 상세히 기술하기로 한다.Hereinafter, a single transistor VCO according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
도 2는 본 고안의 일실시예에 의한 트랜지스터 단일형 VCO가 적용된 PLL회로도로서, 종래와 동일한 부분에 대해서는 동일부호를 붙인다.FIG. 2 is a PLL circuit diagram in which a single transistor VCO is applied according to an embodiment of the present invention, and the same reference numerals are assigned to the same parts as in the related art.
본 고안의 일실시예에 의한 트랜지스터 단일형 VCO는 도 2에 도시한 바와같이 PLL IC(100)가 루프필터(200)를 통해 출력한 주파수 튜닝전압에 의해 결정된 공진주파수신호를 발생하기 위한 것으로, 주파수 결정부(3100), TR3, 발진주파수 정류부(3200) 및 오차 로패스필터(3500)를 구비하고 있다.Transistor single VCO according to an embodiment of the present invention is to generate a resonant frequency signal determined by the frequency tuning voltage output from the PLL IC 100 through the loop filter 200, as shown in FIG. The decision unit 3100, TR3, oscillation frequency rectifier 3200, and error low pass filter 3500 are provided.
상기 주파수 결정부(3100)는 상기 루프필터(200)에서 주파수튜닝전압을 입력받아 상기 TR3의 공진주파수를 결정하는 역할을 하며, 그 구성은 상기 루프필터(3100)에서 수신된 주파수튜닝전압에 반비례하여 커패시턴스값이 가변되는 VC1 및 VC2와, 상기 VC1과 병렬접속된 C1, L1으로 이루어져 있다.The frequency determiner 3100 receives a frequency tuning voltage from the loop filter 200 and determines a resonance frequency of the TR3, and its configuration is inversely proportional to the frequency tuning voltage received from the loop filter 3100. VC1 and VC2 having a variable capacitance value, and C1 and L1 connected in parallel with VC1.
상기 TR3는 상기 주파수 결정부(3100)에 의해 결정된 공진주파수신호를 발생하여 증폭시키는 동시에 상기 PLL IC(100)로 그 공진주파수신호를 피드백시키는 역할을 하며, 베이스단에는 상기 주파수 결정부(3100)가 접속되는 동시에 4.3V 직류전원단에 접속되고, 컬렉터단은 상기 발진주파수 정류부(3200)를 매개로하여 상기 4.3V의 직류전원단과 접속되는 한편, 상기 PLL IC(100)의 피드백 주파수입력단과 접속되어 있다.The TR3 generates and amplifies the resonant frequency signal determined by the frequency determiner 3100, and feeds the resonant frequency signal back to the PLL IC 100, and at the base end, the frequency determiner 3100. Is connected to the 4.3V DC power supply terminal, the collector terminal is connected to the 4.3V DC power supply terminal via the oscillation frequency rectifying unit 3200, and is connected to the feedback frequency input terminal of the PLL IC 100. It is.
상기 발진주파수 정류부(3200)는 R1, L2, L3가 상기 4.3V의 전원단 및 상기 TR3의 컬렉터단에 대해 서로 병렬접속된 형태를 가지며 TR3에서 발생되는 노이즈를 제거하는 역할을 한다.The oscillation frequency rectifier 3200 has a form in which R1, L2, and L3 are connected in parallel to the 4.3V power terminal and the collector terminal of TR3, and removes noise generated in TR3.
상기 오차 로패스필터(3500)는 상기 TR3에서 출력되는 공진주파수를 2단으로 필터링하여 고주파성분 제거하는 특히 2차하모닉성분을 감쇠시키는 역할을 하며, 그 구성은 상기 TR3의 컬렉터단에 대해 서로 병렬접속된 C4 및 L4와, 상기 L4와 각각 병렬 및 직렬접속된 C5 및 L5와, 상기 L5와 병렬접속된 C6로 구성되어 있다.The error low pass filter 3500 serves to attenuate secondary harmonic components, in particular, to remove high frequency components by filtering the resonance frequency output from the TR3 in two stages, and the configuration is parallel to each other with respect to the collector stage of the TR3. C4 and L4 connected, C5 and L5 connected in parallel and series with L4, respectively, and C6 connected in parallel with L5.
상기와 같은 구성을 가지는 본 고안의 일실시예에 의한 트랜지스터 단일형 VCO에 대한 작용을 첨부된 도면을 참조하여 설명하기로 한다.With reference to the accompanying drawings will be described the operation of the transistor unitary VCO according to an embodiment of the present invention having the configuration as described above.
먼저, 루프필터(200)를 통해 주파수튜닝전압이 VCO(3000)에 입력되면 주파수 결정부(3100)의 VC1 및 VC2의 커패시턴스값이 변화되고 이에 따라 주파수 결정부(3100)에서 TR3의 공진주파수가 변화되어 결정된다.First, when the frequency tuning voltage is input to the VCO 3000 through the loop filter 200, capacitance values of VC1 and VC2 of the frequency determiner 3100 are changed, and accordingly, the resonant frequency of TR3 is changed by the frequency determiner 3100. It is changed and determined.
이어서, TR3는 증폭된 상기 공진주파수신호를 출력단으로 출력하는 한편, PLL IC(100)의 피드백주파수입력단으로 피드백시켜준다.TR3 then outputs the amplified resonant frequency signal to an output terminal and feeds it back to the feedback frequency input terminal of the PLL IC 100.
이때, 출력단을 통해 출력되는 공진주파수신호는 발진주파수 정류부(3200)에서 일부 노이즈성분이 제거된후 오차 로패스필터(3500)로 입력되어, 고주파성분 특히 2차하모닉 성분이 제거된후 외부로 출력된다.In this case, the resonant frequency signal output through the output terminal is input to the error low pass filter 3500 after some noise components are removed from the oscillation frequency rectifying unit 3200, and the high frequency components, especially the secondary harmonic components are removed, and then output to the outside. do.
이와같이 트랜지스터 하나만을 사용함에 따라 발생되는 고주파성분 특히, 2차하모닉성분이 상기 오차 로패스필터에서 급격한 감소를 보인다.As such, the high frequency component, in particular, the second harmonic component generated by using only one transistor shows a sharp decrease in the error low pass filter.
도 3은 종래 두 개의 트랜지스터를 사용하는 VCO의 출력단에서 측정한 노이즈특성과 본 고안의 일실시예에 의한 트랜지스터 단일형 VCO의 출력단에서 측정한 노이즈특성을 비교한 표를 도시한 것으로서, PHASE 노이즈 및 PHASE 에러에 있어서는 트랜지스터 두개를 사용것에 비해 하나를 사용할 때 약간 특성이 떨어지는 경향이 있으나 기준 스펙(SPEC)이상의 좋은 결과를 보이며, 2차 하모닉레벨(HARMONIC LEVER)에 있어서는 트랜지스터 두 개를 사용할 때 보다 하나를 사용할 때 더 좋은 결과를 보여준다.3 is a table comparing noise characteristics measured at an output terminal of a conventional VCO using two transistors and noise characteristics measured at an output terminal of a transistor-type VCO according to an embodiment of the present invention. In terms of error, the characteristics tend to be slightly lower when using two transistors compared to the use of two transistors, but the result is better than the SPEC, and in the second harmonic level (HARMONIC LEVER), one is used when using two transistors. Better results when used.
상술한 바와같이 본 고안에 의한 트랜지스터 단일형 VCO에 의하면, 하나의 트랜지스터만 사용하고, 이에 따라 발생되는 2차 하모닉 성분을 오차 로패스필터를 사용하여 감쇠시키는 구성이므로 기존의 트랜지스터 두 개를 사용할 때에 비해 동일한 출력특성을 얻으면서 부품단가를 줄이수 있고, 회로를 단순화 할 수 있다는 뛰어난 효과가 있다.As described above, the single transistor VCO according to the present invention uses only one transistor and attenuates the secondary harmonic component generated by using an error low pass filter. The same output characteristics can reduce the unit cost and the circuit can be simplified.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019990004585U KR20000018545U (en) | 1999-03-22 | 1999-03-22 | Single transistor type vco |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019990004585U KR20000018545U (en) | 1999-03-22 | 1999-03-22 | Single transistor type vco |
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| Publication Number | Publication Date |
|---|---|
| KR20000018545U true KR20000018545U (en) | 2000-10-16 |
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| Application Number | Title | Priority Date | Filing Date |
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| KR2019990004585U KR20000018545U (en) | 1999-03-22 | 1999-03-22 | Single transistor type vco |
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| KR (1) | KR20000018545U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109022286A (en) * | 2017-06-12 | 2018-12-18 | 天津科技大学 | A kind of preparation method of the fermenting agent for reducing grain fruits and vegetables content of beary metal |
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1999
- 1999-03-22 KR KR2019990004585U patent/KR20000018545U/en not_active Application Discontinuation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109022286A (en) * | 2017-06-12 | 2018-12-18 | 天津科技大学 | A kind of preparation method of the fermenting agent for reducing grain fruits and vegetables content of beary metal |
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