CN106209086A - Voltage-controlled oscillator - Google Patents

Voltage-controlled oscillator Download PDF

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Publication number
CN106209086A
CN106209086A CN201610475300.4A CN201610475300A CN106209086A CN 106209086 A CN106209086 A CN 106209086A CN 201610475300 A CN201610475300 A CN 201610475300A CN 106209086 A CN106209086 A CN 106209086A
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CN
China
Prior art keywords
voltage
transistor
delay unit
controlled oscillator
current
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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.)
Pending
Application number
CN201610475300.4A
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Chinese (zh)
Inventor
楼文峰
盛文军
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Micro Electronics (shanghai) Co Ltd
Telink Semiconductor Shanghai Co Ltd
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Micro Electronics (shanghai) Co Ltd
Priority date (The priority date 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 date listed.)
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Application filed by Micro Electronics (shanghai) Co Ltd filed Critical Micro Electronics (shanghai) Co Ltd
Priority to CN201610475300.4A priority Critical patent/CN106209086A/en
Publication of CN106209086A publication Critical patent/CN106209086A/en
Pending legal-status Critical Current

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    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03LAUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00Automatic control of frequency or phase; Synchronisation
    • H03L7/06Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
    • H03L7/08Details of the phase-locked loop
    • H03L7/099Details of the phase-locked loop concerning mainly the controlled oscillator of the loop
    • H03L7/0995Details of the phase-locked loop concerning mainly the controlled oscillator of the loop the oscillator comprising a ring oscillator

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  • Pulse Circuits (AREA)

Abstract

The present invention relates to electronic circuit technology field, disclose a kind of voltage-controlled oscillator, there is high linearity.This voltage-controlled oscillator includes: time delay module, is used for producing oscillator signal;Voltage-to-current conversion circuit, for being converted to driving electric current by control voltage;And current mirror, for by described driven current mirror picture to described time delay module, as the operating current of described time delay module;Wherein, described voltage-to-current conversion circuit be linear voltage to current converter circuit so that the frequency of described oscillator signal and described control voltage linear relation.It addition, the delay unit in time delay module uses output common mode voltage self-stabilization technology, thus obtain stable output common mode level.Voltage-controlled oscillator disclosed by the invention, tool High Linear characteristic and stable output common mode voltage.

Description

Voltage-controlled oscillator
Technical field
The present invention relates to electronic circuit technology field, particularly to a kind of voltage-controlled oscillator, there is High Linear Spend and stablize common mode output voltage.
Background technology
Agitator (oscillator) is a kind of energy conversion device, direct current energy can be converted to have certain frequency AC energy.Agitator can be as RF SoC (radio frequency system on chip, RF_SOC) Pith, and be chip provide clock signal or for receiving-transmitting chain provide local carrier signal.According to division, agitator can To be divided into outer Induced Oscillation device and interior Induced Oscillation device, its China and foreign countries' Induced Oscillation device is also called " Control of Voltage agitator or Control of Voltage Agitator ", and the agitator that the interior i.e. no-voltage of Induced Oscillation device controls.Wherein, voltage-controlled oscillator can be divided into again Control of Voltage Ring oscillator and Control of Voltage inductor-capacitor agitator, both are applied to different occasions according to different requirements.Wherein, Ring oscillator is widely used in the application of clock type and low frequency or MF communication.It is typically by several phases Same delay unit one loop of composition, delay unit therein can use single-ended format or difference form, specifically distinguish As shown in Fig. 1 (a) and Fig. 1 (b).
Present inventor is applied to phaselocked loop (phase locked in practice, it has been found that work as ring oscillator Loop, PLL) in frequency synthesizer, during to produce stable output frequency, ring oscillator, by the Control of Voltage of loop, is formed Voltage-controlled oscillator.Now, it is desirable to voltage-controlled oscillator (the most annular voltage controlled oscillating circuit) is in the control of work Voltage range processed can have the preferable linearity, thus ensures the preferable loop stability of PLL and performance.But, current Voltage-controlled oscillator does not has characteristics that, therefore the real necessity having improvement of prior art.
Summary of the invention
It is an object of the invention to provide a kind of voltage-controlled oscillator, there is preferable linear characteristic.
For solving above-mentioned technical problem, embodiments of the present invention provide a kind of voltage-controlled oscillator, comprise: Time delay module, is used for producing oscillator signal;Voltage-to-current conversion circuit, for being converted to driving electric current by control voltage;With And current mirror, for by described driven current mirror picture to described time delay module, as the operating current of described time delay module;Its In, described voltage-to-current conversion circuit be linear voltage to current converter circuit so that the frequency of described oscillator signal with Described control voltage linear relation.
Present embodiment in terms of existing technologies, by linear voltage-to-current conversion circuit, improves vibration The frequency of signal and the linear relationship controlling voltage, thus obtain the voltage-controlled oscillator of high linearity.
It addition, described voltage-to-current conversion circuit includes: the first transistor, its grid terminates described control voltage, its Drain electrode terminates described current mirror;And resistor, one terminates the source electrode of described the first transistor, other end ground connection.This implements In mode, voltage-to-current conversion circuit adds the structure of resistance by transistor, improves frequency and the control electricity of oscillator signal The linear relationship of pressure.
It addition, described resistor is rheostat, then can be adjusted by the resistance adjusting described rheostat The linearity between frequency and the described control voltage of described oscillator signal.
It addition, the source electrode of described the first transistor is connected with the substrate of described the first transistor, to reduce this transistor Threshold voltage, such that it is able to extension output controls the excursion of voltage, and improves the linearity of this transistor.
Described time delay module includes: the delay unit of multiple series connection, and described current mirror is for by described driving electric current respectively There is provided to described delay unit;
It addition, the linear relationship between the frequency of described oscillator signal and described control voltage is:
f o s c ∝ V s R v C × V s w
Wherein, foscFor the frequency of described oscillator signal, VsFor described control voltage, RvResistance for described rheostat Value, Vsw is the amplitude of oscillation of the output voltage of described delay unit, and C is the parasitic capacitance of the outfan of described delay unit.
It addition, the plurality of delay unit is the delay unit of differential-input differential output form.
It addition, the plurality of delay unit all uses the feedback form of local Commom-mode feedback.This embodiment, employing office The feedback form of portion's Commom-mode feedback, can improve the stability of structure, and realize low power dissipation design.
It addition, each delay unit in the plurality of delay unit all includes: transistor seconds;Third transistor, its Grid couples with the grid of described transistor seconds, the source electrode of its source electrode and described transistor seconds and couple;4th is brilliant Body pipe, its drain electrode is connected with the drain electrode of described second crystal, and its grid is the positive input of this delay unit;5th crystal Pipe, its drain electrode is connected with the drain electrode of described 3rd crystal, and its grid is the negative input of described delay unit, its source electrode and institute The output of the source electrode and described current mirror of stating the 4th transistor couples;Second resistor;And the 3rd resistor, described second Resistor and described 3rd resistor string are connected on described in described 4th transistor between the drain electrode of the 5th transistor, and described second The junction point of resistor and described 3rd resistor is additionally coupled to the grid of described transistor seconds.
Accompanying drawing explanation
Fig. 1 (a) be in existing ring oscillator delay unit use single-ended format structural representation;
Fig. 1 (b) is the structural representation that in existing ring oscillator, delay unit uses difference form;
Fig. 2 is the structural representation of the voltage-controlled oscillator according to first embodiment of the invention;
Fig. 3 is the structural representation of the voltage-controlled oscillator according to second embodiment of the invention;
Fig. 4 is the structural representation of delay unit in Fig. 3.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with the accompanying drawing each reality to the present invention The mode of executing is explained in detail.But, it will be understood by those skilled in the art that in each embodiment of the present invention, In order to make reader be more fully understood that, the application proposes many ins and outs.But, even if there is no these ins and outs and base Many variations and amendment in following embodiment, it is also possible to realize the application each claim technical side required for protection Case.
First embodiment of the present invention relates to a kind of voltage-controlled oscillator.Concrete structure is as shown in Figure 2.This electricity Voltage-controlled ring oscillator processed 2, comprises: time delay module 21, voltage-to-current conversion circuit 22 and current mirror 23.
Wherein, voltage-to-current conversion circuit 22 will be for controlling voltage VctrlBe converted to drive electric current I.Current mirror 23, For driving electric current I mirror image that voltage-to-current conversion circuit 22 is changed to time delay module 21, using as time delay module 21 Operating current is (such as Idelay).Wherein, time delay module 21, under the driving effect of operating current, produces oscillator signal, and this vibration is believed Number frequency can depend on that this driving electric current, i.e. voltage-to-current conversion circuit 22 are current generated.For the technology of the present invention For personnel, understanding that time delay module, how under the driving of operating current, produces oscillator signal, therefore this process is the most detailed Repeat.
Present embodiment, voltage-to-current conversion circuit 22 can be linear circuit, so that what time delay module 21 produced The frequency of oscillator signal and control voltage VctrlIn the highest linear relationship, thus obtain the Control of Voltage annular of high linearity Agitator.
Second embodiment of the present invention relates to a kind of voltage-controlled oscillator, as shown in Figure 3.Second embodiment It it is the further refinement to circuit module each in the first embodiment.Specifically, as it is shown on figure 3, voltage is to electric current conversion electricity Road 22 includes: transistor M1, and it can be N-type MOS (metal-oxide semiconductor (MOS)) transistor;And resistor RV, it is permissible For rheostat.
As it is shown on figure 3, the grid termination of transistor M1 controls voltage Vctrl, drain electrode termination current mirror 23.And resistor RV's The source electrode of one termination transistor M1, other end ground connection (such as reference).In the example shown, the source electrode of transistor M1 connects substrate, thus Reduce the threshold voltage (V of transistor M1th), and then extend the excursion of output control voltage and improve the line of transistor M1 Property degree.
It addition, resistor RVCan resistance adjustable, such that it is able to by adjust rheostat RVResistance adjust this voltage Control frequency and the control voltage V of the oscillator signal of ring oscillator 2 outputctrlBetween the linearity.
Wherein, the mutual conductance expression formula of transistor M1 is:From this expression formula, variable resistance When the Rv transimpedance compared to transistor M1 is much bigger, effective mutual conductance of transistor M1 is linear with Rv.By adjusting Whole resistor RVResistance can change the value of effective mutual conductance of this transistor M1
Continue as it is shown on figure 3, time delay module 21 includes: the delay unit of multiple series connection, such as delay unit 211, time delay list Unit 212 and delay unit 213, it should be noted that the quantity of delay unit is not so limited in time delay module 21.
As it is shown on figure 3, delay unit 211, delay unit 212 and delay unit 213 are provided work by current mirror 23 for it Make electric current, and vibrate under the effect of this electric current, the oscillator signal needed for producing.
Bear as it is shown on figure 3, the feedback system of delay unit 211, delay unit 212 and delay unit 213 is local common mode Feedback.So-called local common-mode feedback is exactly that the differential signal of circuit self directly oneself feeds back, it is not necessary to external common-mode is joined Examine what voltage carried out feeding back.This kind of feedback system, it is not necessary to external common-mode voltage, therefore can reduce power consumption, meet lower powered Design requirement.
As it is shown on figure 3, current mirror 23 is mainly made up of multiple transistors, the plurality of transistor can be p-type MOS crystal Managing, and the grid of these transistors is coupled together, source electrode is both coupled to supply voltage (VDD), and drains and be respectively coupled to Different parts, as shown in the drain electrode of leftmost transistor be coupled to the drain electrode of transistor M1.On the right of in diagram three Transistor is respectively delay unit 211, delay unit 212 and delay unit 213 and provides delaying current Idelay°
In the present embodiment, between frequency and the control voltage of the oscillator signal of whole voltage-controlled oscillator 2 Linear relationship can be expressed as:
f o s c ∝ 1 T d ∝ I d e l a y C × V s w ∝ V s / R v C × V s w = V s R v C × V s w
Wherein, foscFor the frequency of described oscillator signal, Td is delay time (namely the work of the delay unit of ring oscillation Make the discharge and recharge time of electric current), IdelayFor the operating current of delay unit, VsFor controlling voltage (Vctrl), C is that delay unit is defeated Going out the parasitic capacitance at two ends or fixing load capacitance, Vsw is the amplitude of oscillation of delay unit output voltage, RvFor rheostat Resistance.
Third embodiment of the present invention relates to a kind of delay unit, as shown in Figure 4.3rd embodiment is real to second Execute the further refinement of delay unit in mode, comprising: transistor MN1, transistor MN2, transistor MP1, transistor MP2, Resistance R1 and resistance R2.Transistor MN1 and transistor MN2 is N-type metal-oxide-semiconductor, and transistor MP1 and transistor MP2 is p-type MOS Pipe.
Wherein, the grid of transistor MP1 is the positive input INP of this delay unit, and the grid of transistor MP2 is time delay The negative input INN of unit.The grid of transistor MN2 couples with the grid of transistor MN1, transistor MN2 source electrode and crystal The source electrode of pipe MN1 and couple.The drain electrode of transistor MP1 is connected with the drain electrode of transistor MN1.The drain electrode of transistor MP2 with The drain electrode of transistor MN2 connects, and the source electrode of transistor MP2 couples with the source electrode of transistor MP1 and the outfan of current mirror.
Wherein, resistance R1 and resistance R2 is serially connected between the drain electrode of transistor MP1 and transistor MP2, and resistance R1 and electricity The junction point of resistance R2 is additionally coupled to the grid of transistor MN1.
It addition, also concatenated filter capacitor C1 between the grid and ground of transistor MN1, for feedback common-mode voltage is entered Row filtering.
The embodiment of the present invention, voltage-controlled oscillator therein is compared to existing voltage-controlled oscillator Speech, has the high linearity and stable output common mode voltage.
It is noted that each module involved in present embodiment is logic module, in actual applications, one Individual logical block can be a physical location, it is also possible to be a part for a physical location, it is also possible to multiple physics lists The combination of unit realizes.Additionally, for the innovative part highlighting the present invention, will be with solution institute of the present invention in present embodiment The unit that the technical problem relation of proposition is the closest introduces, but this is not intended that in present embodiment the list that there is not other Unit.
It will be understood by those skilled in the art that the respective embodiments described above are to realize the specific embodiment of the present invention, And in actual applications, can to it, various changes can be made in the form and details, without departing from the spirit and scope of the present invention.

Claims (10)

1. a voltage-controlled oscillator, it is characterised in that comprise:
Time delay module, is used for producing oscillator signal;
Voltage-to-current conversion circuit, for being converted to driving electric current by control voltage;And
Current mirror, for by described driven current mirror picture to described time delay module, as the operating current of described time delay module;
Wherein, described voltage-to-current conversion circuit is linear voltage to current converter circuit, so that described oscillator signal Frequency and described control voltage linear relation.
Voltage-controlled oscillator the most according to claim 1, it is characterised in that described voltage-to-current conversion circuit Including:
The first transistor, its grid terminates described control voltage, and its drain electrode terminates described current mirror;And
Resistor, one terminates the source electrode of described the first transistor, other end ground connection.
Voltage-controlled oscillator the most according to claim 2, it is characterised in that described resistor is variable resistance Device, adjusts the pass between the frequency of described oscillator signal and described control voltage by the resistance adjusting described rheostat System.
Voltage-controlled oscillator the most according to claim 2, it is characterised in that the source electrode of described the first transistor with The substrate of described the first transistor connects.
Voltage-controlled oscillator the most according to claim 3, it is characterised in that described time delay module includes: multiple The delay unit of series connection, described current mirror is for providing described driving electric current respectively to described delay unit;
Wherein, the linear relationship between frequency and the described control voltage of described oscillator signal is:
f o s c ∝ V s R v C × V s w
Wherein, foscFor the frequency of described oscillator signal, VsFor described control voltage, RvFor the resistance of described rheostat, Vsw For the amplitude of oscillation of the output voltage of described delay unit, C is parasitic capacitance or the load capacitance of the outfan of described delay unit.
Voltage-controlled oscillator the most according to any one of claim 1 to 4, it is characterised in that described time delay mould Block includes: the delay unit of multiple series connection, and described current mirror is for providing described driving electric current respectively to described delay unit.
Voltage-controlled oscillator the most according to claim 6, it is characterised in that the plurality of delay unit is difference Divide the delay unit of input difference output form.
Voltage-controlled oscillator the most according to claim 6, it is characterised in that the plurality of delay unit all uses The locally feedback form of Commom-mode feedback.
Voltage-controlled oscillator the most according to claim 7, it is characterised in that every in the plurality of delay unit Individual delay unit all includes:
Transistor seconds;
Third transistor, its grid couples with the grid of described transistor seconds, its source electrode and the source electrode of described transistor seconds And couple;
4th transistor, its drain electrode is connected with the drain electrode of described second crystal, and its grid is the positive input of this delay unit;
5th transistor, its drain electrode is connected with the drain electrode of described 3rd crystal, and its grid is the negative sense input of described delay unit End, its source electrode couples with the described source electrode of the 4th transistor and the output of described current mirror;
Second resistor;And
3rd resistor, described second resistor and described 3rd resistor string are connected on the 5th crystal described in described 4th transistor Between the drain electrode of pipe, and the junction point of described second resistor and described 3rd resistor is additionally coupled to described transistor seconds Grid.
Voltage-controlled oscillator the most according to claim 9, it is characterised in that described transistor seconds and described Third transistor is N-type metal-oxide-semiconductor, and described 4th transistor and described 5th transistor are p-type metal-oxide-semiconductor.
CN201610475300.4A 2016-06-26 2016-06-26 Voltage-controlled oscillator Pending CN106209086A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106888004A (en) * 2017-01-10 2017-06-23 西安紫光国芯半导体有限公司 A kind of ring oscillator
CN109167571A (en) * 2018-08-13 2019-01-08 中科芯集成电路股份有限公司 A kind of low-power consumption ring oscillator and its implementation
CN110365332A (en) * 2019-05-30 2019-10-22 芯创智(北京)微电子有限公司 A kind of number/voltage-controlled oscillator of low supply voltage
CN113794446A (en) * 2021-09-17 2021-12-14 上海磐启微电子有限公司 RC oscillator with frequency not changing with temperature and power supply voltage
TWI800644B (en) * 2018-07-13 2023-05-01 南韓商三星電子股份有限公司 Digitally-controlled oscillators
WO2023155485A1 (en) * 2022-02-21 2023-08-24 华为技术有限公司 Ring voltage-controlled oscillator and driving method therefor, phase-locked loop, and electronic device

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CN1627628A (en) * 2003-12-10 2005-06-15 上海贝岭股份有限公司 Annular voltage controlled oscillator operated in differential signal and low voltage
US20080197932A1 (en) * 2007-02-20 2008-08-21 Elpida Memory, Inc. Voltage controlled oscillator
CN101527567A (en) * 2008-03-06 2009-09-09 瑞昱半导体股份有限公司 Clock and data recovery circuit
CN103036558A (en) * 2011-09-30 2013-04-10 中芯国际集成电路制造(上海)有限公司 Voltage-controlled oscillator
CN104300971A (en) * 2013-07-17 2015-01-21 北京兆易创新科技股份有限公司 Frequency stabilized ring oscillator

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1627628A (en) * 2003-12-10 2005-06-15 上海贝岭股份有限公司 Annular voltage controlled oscillator operated in differential signal and low voltage
US20080197932A1 (en) * 2007-02-20 2008-08-21 Elpida Memory, Inc. Voltage controlled oscillator
CN101527567A (en) * 2008-03-06 2009-09-09 瑞昱半导体股份有限公司 Clock and data recovery circuit
CN103036558A (en) * 2011-09-30 2013-04-10 中芯国际集成电路制造(上海)有限公司 Voltage-controlled oscillator
CN104300971A (en) * 2013-07-17 2015-01-21 北京兆易创新科技股份有限公司 Frequency stabilized ring oscillator

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106888004A (en) * 2017-01-10 2017-06-23 西安紫光国芯半导体有限公司 A kind of ring oscillator
TWI800644B (en) * 2018-07-13 2023-05-01 南韓商三星電子股份有限公司 Digitally-controlled oscillators
CN109167571A (en) * 2018-08-13 2019-01-08 中科芯集成电路股份有限公司 A kind of low-power consumption ring oscillator and its implementation
CN110365332A (en) * 2019-05-30 2019-10-22 芯创智(北京)微电子有限公司 A kind of number/voltage-controlled oscillator of low supply voltage
CN113794446A (en) * 2021-09-17 2021-12-14 上海磐启微电子有限公司 RC oscillator with frequency not changing with temperature and power supply voltage
CN113794446B (en) * 2021-09-17 2023-10-27 上海磐启微电子有限公司 RC oscillator with frequency not changing with temperature and power supply voltage
WO2023155485A1 (en) * 2022-02-21 2023-08-24 华为技术有限公司 Ring voltage-controlled oscillator and driving method therefor, phase-locked loop, and electronic device

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