CN1980029A - Control circuit with frequency regulation to reduce power supply converter electro-magnetic interference - Google Patents

Control circuit with frequency regulation to reduce power supply converter electro-magnetic interference Download PDF

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CN1980029A
CN1980029A CN 200510128928 CN200510128928A CN1980029A CN 1980029 A CN1980029 A CN 1980029A CN 200510128928 CN200510128928 CN 200510128928 CN 200510128928 A CN200510128928 A CN 200510128928A CN 1980029 A CN1980029 A CN 1980029A
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CN100472925C (en
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杨大勇
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Fairchild Taiwan Corp
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System General Corp Taiwan
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Abstract

The control circuit is in use for reducing electromagnetic interference of a power supply converter. Being coupled to a feedback circuit, a switching circuit is in use for generating switch signal to adjust an output of the power supply converter. A first oscillator is in use for deciding switching frequency of a switch signal. Being coupled to the first oscillator, a second oscillator is in use for modulating switching frequency of the switch signal in order to reduce electromagnetic interference. A digital control resistor is in use for attenuating a feedback signal from a feedback circuit. Output of the second oscillator is coupled the digital control resistor in order to control resistance value of the digital control resistor. Thus, when switching frequency is modulated, output power and output voltage can be kept a fixed value.

Description

Has frequency modulating to reduce the control circuit of power supply changeover device electromagnetic interference
Technical field
The invention relates to a kind of power supply changeover device, and particularly about a kind of control of switch type power converter.
Background technology
Power supply changeover device (power converter) is to be used for converting a unregulated supply to a voltage or an electric current of regulating.Fig. 1 illustrates a conventional power source transducer, and wherein a control circuit 10 is to include a frequency setting end RT, a back coupling end FB, a switching output SW and a current sense end VS, and wherein this control circuit 10 produces a switching signal V SW, switch a transformer 30 in order to control a transistor 20.One resistor 40 is to be used for one of this transformer 30 of sensing to switch electric current I PTo carry out switching controls.One resistor 45 is with a switching frequency that decides this control circuit 10.This back coupling end FB of this control circuit 10 is an output that is connected to a feedback circuit 50.This feedback circuit 50 is to be coupled to the output of power supply changeover device to produce a feedback signal V FBAccording to this feedback signal V FB, this switching signal V SWWork period (duty cycle) be the power that has determined to be sent to the output of power supply changeover device from the input of power supply.Though handoff technique makes that the volume of power supply changeover device is dwindled, (electric andmagnetic interference EMI) has influenced power supply and ancillary equipment thereof to the electromagnetic interference that changeover module produced.Therefore need to dispose the solution (for example electromagnetic interface filter, transformer screen protect etc.) of electromagnetic interference in the power supply changeover device, to reduce electromagnetic interference.Yet the solution of electromagnetic interference but causes the loss of power, has also increased the volume and the cost of power supply changeover device simultaneously.In the immediate development, many known technologies all reduce electromagnetic interference at this frequency of utilization modulation (frequency modulation) or frequency hopping means such as (frequency hopping).Known technology " Reduction of PowerSupply EMI Emission by Switching Frequency Modulation " (IEEE Transactions on Power Electronics for example, VOL.9.No.1.January 1994), " Effects of Switching FrequencyModulation on EMI Performance of a Converter Using SpreadSpectrum Approach " (Applied Power ElectronicsConference and Exposition, 2002,17-Annual, IEEE, Volume 1,10-14, March, 2002, Pages:93-99), United States Patent (USP) announces the 6th, 229, No. 366 " OfflineConverter with Integrated Softstart and FrequencyJitter " (May 8,2001) and United States Patent (USP) announce the 6th, 249, No. 876 " Frequency Jittering Control for Varying theSwitching Frequency of a Power Supply " (Jun.19,2001) or the like.Yet the shortcoming of known technology is that " frequency modulating " can produce unexpected ripple signal (ripple signal) in the output of power supply changeover device.
Being produced unexpected ripple signal by frequency modulating will be described as follows.The power output P of power supply changeover device OIt is the output voltage V of power supply changeover device OWith output current I OProduct, its relational expression is:
P O=Vo×Io=η×P IN_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_?_(1)
The input power P of this transformer 30 INWith switch current I PRelation is shown below
P IN = 1 2 × T × L P × I P 2
I P = V IN L P × T ON
Wherein η is the efficient (efficiency) of transformer 30, V INBe the input voltage of transformer 30, L PBe the primary side inductance (primaryinductance) of transformer 30, T is switching signal V SWSwitching cycle (switchingperiod), T ONBe switching signal V SWON time (on-time).
Equation (1) can be rewritten as
P O = η × V IN 2 × T ON 2 2 × L P × T - - - - - - - - - - - - - - - - - - - - - - - - ( 2 )
Owing to switching cycle T changes according to frequency modulating.Shown in equation (2), when switching cycle T changes, power output P OWill change.Therefore, as power output P ODuring change, will produce unexpected ripple signal.
The other shortcoming of known technology is unexpected frequency modulating scope.Its frequency modulating scope is relevant with the setting of switching frequency.Therefore, when setting its switching frequency according to different application, the effect that reduces electromagnetic interference is unclear with making.
Summary of the invention
The purpose of this invention is to provide a kind of control circuit, to reduce the electromagnetic interference (EMI) of power supply changeover device (power converter) with frequency modulating.
Another purpose of the present invention provides a kind of control circuit with frequency modulating, to avoid producing unexpected ripple signal in the output of power supply changeover device.
Based on above-mentioned and other purpose, the present invention proposes a kind of control circuit with frequency modulating, in order to control a power supply changeover device, it is characterized in that, this control circuit comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to produce a clock pulse signal to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the frequency of this clock signal of modulation;
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator includes a coding circuit to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is in order to controlling the switching frequency of this numerical control capacitor with this switching signal of modulation, and in order to control this digit-control resistance device to determine the attenuation rate of this feedback signal.
Wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being formed by many groups of indivedual regulating switch and modulation capacitors of connecting, and those regulating switch are to control its keying by this data signal groups.
Wherein this digit-control resistance device comprises:
Many group convert resistances are right, and those convert resistances are to being connected in parallel to each other, wherein those convert resistances to be by the attenuator switch of many groups of indivedual series connection and damping resistance device couple mutually form, those attenuator switch are to control its keying by this data signal groups.
Wherein this first oscillator comprises:
One charging current source is in order to produce a charging current;
One discharging current source is in order to produce a discharging current;
One oscillating capacitor is to be in parallel with this numerical control capacitor;
One charge switch is to be connected between this charging current source and this oscillating capacitor;
One discharge switch is connected between this discharging current source and this oscillating capacitor;
One first comparator, one first input is supplied by one first reference voltage, and one second input is to be connected to this oscillating capacitor;
One second comparator, one first input is to be connected to this oscillating capacitor, and one second input is supplied by one second reference voltage, and wherein this first reference voltage is to be higher than this second reference voltage;
One first lock, in order to produce this clock signal to determine the switching frequency of this switching signal, wherein one first of this first lock input is an output that is coupled to this first comparator, wherein one of this first lock output is in order to open and close this discharge switch; And
One second lock, its two inputs are connected to this output of this first lock and an output of this second comparator respectively, and an output of this second lock is one second input that is connected to this first lock, wherein one of this second lock output is in order to open and close this charge switch.
Wherein this coding circuit comprises:
A plurality of comparators, the positive input of those comparators are to be connected to this oscillator signal, and the negative input of those comparators is supplied by corresponding many group reference voltages respectively;
A plurality of flip-flops, the input of those flip-flops are the output that is coupled to those comparators respectively, and wherein the input of the clock pulse of those flip-flops is supplied by this clock signal; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
A kind of control circuit with frequency modulating of the present invention, is characterized in that this control circuit comprises in order to control a power supply changeover device:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation;
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator includes an analog-digital converter, in order to produce a data signal groups according to this oscillator signal; And
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; Wherein this data signal groups is controlled the resistance value of capacitance and this digit-control resistance device of this numerical control capacitor.
Wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being that regulating switch and modulation capacitors by many groups of indivedual series connection are formed, and open and close those regulating switch by this data signal groups.
Wherein this digit-control resistance device comprises:
Many group convert resistances are right, and those convert resistances are to being connected in parallel to each other, and wherein those convert resistances are to being that attenuator switch and damping resistance devices by many groups of indivedual series connection are formed, and open and close those attenuator switch by this data signal groups.
Wherein this first oscillator comprises:
One charging current source is in order to produce a charging current;
One discharging current source is in order to produce a discharging current;
One oscillating capacitor is in parallel with this numerical control capacitor;
One charge switch is connected between this charging current source and this oscillating capacitor;
One discharge switch is connected between this discharging current source and this oscillating capacitor;
One first comparator, one first input is provided by one first reference voltage, and one second input is to be connected to this oscillating capacitor;
One second comparator, one first input is connected to this oscillating capacitor, and one second input is provided by one second reference voltage, and wherein this first reference voltage is to be higher than this second reference voltage;
One first lock is coupled to this commutation circuit, and in order to determine the switching frequency of this switching signal, wherein one first of this first lock input is an output that is coupled to this first comparator, and wherein one of this first lock output is in order to open and close this discharge switch; And
One second lock, its two inputs are connected to this output of this first lock and an output of this second comparator respectively, and an output of this second lock is one second input that is connected to this first lock, wherein one of this second lock output is in order to open and close this charge switch.
Wherein this analog-digital converter comprises:
A plurality of comparators, the positive input of those comparators is supplied by this oscillator signal, and the negative input of those comparators is supplied by many groups reference voltage of correspondence respectively;
A plurality of flip-flops, the input of those flip-flops is coupled to the output of those comparators respectively, and wherein the clock pulse of those flip-flops input is that output by this first oscillator is provided; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
A kind of control circuit with frequency modulating of the present invention, is characterized in that this controller comprises in order to control a power supply changeover device:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator comprises a coding circuit, in order to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is in order to control the capacitance of this numerical control capacitor.
Wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being that regulating switch and modulation capacitor by indivedual series connection formed, and open and close those regulating switch by this data signal groups.
Wherein this coding circuit comprises:
A plurality of comparators, the positive input of those comparators is supplied by this oscillator signal, and the negative input of those comparators is then provided by many groups reference voltage of its correspondence respectively;
A plurality of flip-flops, the input of those flip-flops are the output that is coupled to those comparators respectively, and wherein the input of the clock pulse of those flip-flops is the output that is connected to this first oscillator; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
A kind of controller with frequency modulating of the present invention, is characterized in that this controller comprises in order to control a power supply changeover device:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One second oscillator is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation; And
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; Wherein this second oscillator is coupled to this digit-control resistance device, to control the resistance value of this digit-control resistance device.
A kind of control circuit with frequency modulating of the present invention, is characterized in that this control circuit comprises in order to control a power supply changeover device:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator comprises a coding circuit, in order to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is to be coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation.
The present invention because of modulation the switching frequency of this switching signal, therefore launched to switch the frequency spectrum of energy, thereby reduced the electromagnetic interference of power supply changeover device.In addition, because this data signal groups has been controlled the attenuation rate (it is controlling an ON time of this switching signal) of this feedback signal, therefore can compensate its variation by this switching frequency modulation, and keeping power output and output voltage is definite value, to avoid producing unexpected ripple signal in the output of power supply changeover device.
Description of drawings
For above and other objects of the present invention, feature and advantage can be become apparent, preferred embodiment cited below particularly, and conjunction with figs. are described in detail below, wherein:
Fig. 1 illustrates explanation one known power source transducer.
Fig. 2 is the circuit diagram that illustrates a control circuit of the present invention.
Fig. 3 is the calcspar that illustrates an oscillating circuit of the present invention.
Fig. 4 is the circuit diagram that illustrates one second oscillator of the present invention.
Fig. 5 is the circuit diagram that illustrates a coding circuit of the present invention.
Fig. 6 is an oscillator signal oscillogram that illustrates this second oscillator of the present invention.
Fig. 7 is the circuit diagram that illustrates one first oscillator of the present invention.
Fig. 8 is a serrated signal and a clock pulse signal waveforms that illustrates this first oscillator of the present invention.
Fig. 9 illustrates the circuit diagram of the present invention in order to two current sources of decision switching frequency.
Embodiment
Fig. 1 illustrates a kind of conventional power source transducer.One control circuit 10 is to be coupled to a feedback circuit 50, switches signal V to produce one SWAnd the output of adjusting power supply changeover device, this feedback circuit 50 is the output that is coupled to power supply changeover device, to produce a feedback signal V FBThis switching signal V wherein SWBe according to this feedback signal V FBAnd change.One of one transformer 30 switches electric current I PBe to be converted into one to switch current signal V via a sense resistor 40 SThis switch current signal V SOffer this control circuit 10, produce this switching signal V according to this SW
Fig. 2 is the circuit diagram that illustrates control circuit 10 of the present invention.In control circuit 10, one switch circuit comprise comparator 71,72, flip-flop 75, inverter 70, with door 73,79, diode 80 and resistor 90,91,92,93.Resistor 90 is in order to draw high a back coupling end FB.This feedbacks end FB with this feedback signal V FBBe connected to resistor 91 via diode 80.Diode 80 makes this feedback signal V FBAccurate bit shift.Resistor the 91,92, the 93rd, this feedback signal that decays V FBTo reduce the feedback loop (feedback loop) of loop gain (loop gain) in order to the stabilized power supply transducer.This resistor 92 is connected between this resistor 91 and this resistor 93, and these resistor 93 ground connection.Resistor 91 and this comparator 71 positive inputs of being connected of 92 produce a decay feedback voltage V FB'.This switch current signal V SIt is the negative input that is supplied to this comparator 71.Via this and door 73, the output of this comparator 71 is replacement ends that are coupled to this flip-flop 75.This switch current signal V SMore be supplied to a negative input of this comparator 72.One positive input of this comparator 72 is by a reference voltage V TSupply.Via this and door 73, one of this comparator 72 is exported this flip-flop 75 that also is used to reset.One clock pulse signal PLS triggers this flip-flop 75 via this inverter 70.One output of this inverter 70 more is connected to this and a door input of 79.Should then be connected to an output of this flip-flop 75 with another input of door 79.Should produce this switching signal V with an output of door 79 SWTherefore, this switching signal V SWSwitch according to this clock signal PLS.In case this switch current signal V SBe higher than this decay feedback voltage V FB' and this reference voltage V T, switching signal V SWTo be closed (turned off) immediately.
One swings circuit 100 produces this clock signal PLS and data signal groups N n~N 0One resistor 45 sees through a link RT and connects this oscillating circuit 100, in order to determine the frequency of oscillation of this clock signal PLS.One digit-control resistance device 101 is in parallel with this resistor 93, in order to set this feedback signal V FBAttenuation rate.This digit-control resistance device 101 comprises that many groups convert resistance parallel with one another is right, and wherein each convert resistance is to being formed by resistor 99~94 and switch 89~84 difference.Wherein switch 84 is connected with resistor 94.Switch 89 is connected with resistor 99.Data signal groups N n~N 0Controlling switch 89~84 via inverter 109~104, to change the resistance value of this digit-control resistance device 101.
With reference to figure 3, this oscillating circuit 100 comprises one first oscillator 300 and second oscillator 200.This first oscillator 300 produces this clock signal PLS, and this second oscillator then produces data signal groups N n~N 0This link RT is connected to this first oscillator 300.Fig. 4 is the circuit diagram that illustrates this second oscillator 200 of the present invention.This second oscillator 200 comprises a current source 225, and in order to produce a charging current, 226 of current sources produce a discharging current.One switch 227 is to be connected between this current source 225 and the capacitor 210.One switch 228 is to be connected between this current source 226 and this capacitor 210.Therefore on this capacitor 210, produce an oscillator signal WAV.Reference voltage V on one first HSOne first input to a comparator 230 is provided.One second input of this comparator 230 is connected to this capacitor 210.One first time reference voltage V LSOne second input to a comparator 235 is provided.One first input of this comparator 235 is to be connected to this capacitor 210.This reference voltage V on first HSBe to be higher than this first time reference voltage V LSOne output of this comparator 230 is one first inputs that are connected to a NAND gate 240, and an output of this NAND gate 240 is in order to keying (turn on/off) this switch 228, and this output of this NAND gate 240 more sees through an inverter 220 in order to open and close this switch 227.Two inputs of one NAND gate 245 are connected to this output of this NAND gate 240 and an output of this comparator 235 respectively.One output of NAND gate 245 is one second inputs that are connected to this NAND gate 240.One coding circuit 250 is to produce this data signal groups N according to this oscillator signal WAV n~N 0
Fig. 5 is the circuit diagram that illustrates this coding circuit 250 of the present invention.Operation at this this coding circuit 250 can be considered an analog-digital converter.This coding circuit 250 comprises comparator 251~255, and the quantity of comparator 251~255 can the arbitrary decision according to needs.The positive input of comparator 251~255 is supplied by oscillator signal WAV.Reference voltage V R1~V R5Be supplied to the negative input of comparator 251~255 respectively.The input of flip-flop 261~265 is coupled to the output of comparator 251~255 respectively.The clock pulse input of flip-flop 261~265 is supplied by this clock signal PLS.Therefore the output state of comparator 251~255 promptly is latched respectively in flip-flop 261~265 according to this clock signal PLS.One encoder 270 is the output that is coupled to flip-flop 261~265, in order to produce data signal groups N n~N 0
Fig. 6 is the oscillogram that illustrates this oscillator signal WAV of the present invention.Data signal groups N n~N 0Be to produce according to this oscillator signal WAV.T among the figure HThe cycle of representing this oscillator signal WAV.
Fig. 7 is the circuit diagram that illustrates this first oscillator 300 of the present invention.First oscillator 300 comprises a current source 325, in order to produce a charging current I 325326 of one current sources are used for producing a discharging current I 326One capacitor 320 is in parallel with a numerical control capacitor 500.This numerical control capacitor 500 is to composing in parallel by many groups switch-capacitor.Each switch-capacitor is to being to be connected respectively with switch 351~359 and formed by capacitor 311~319, and wherein switch 351~359 is respectively according to data signal groups N n~N 0And open and close.Therefore, for the modulation switching frequency, the capacitance of numerical control capacitor 500 can be by data signal groups N n~N 0And set.
One switch 327 is to be connected between this current source 325 and this capacitor 320.One switch 328 is to be connected between this current source 326 and this capacitor 320.Reference voltage V on one second HMBe supplied to one first input of a comparator 330.One second input of this comparator 330 is to be connected to this capacitor 320.One second time reference voltage V LMBe supplied to one second input of a comparator 335.One first input of this comparator 335 is to be connected to this capacitor 320.This reference voltage V on second HMBe higher than this second time reference voltage V LmOne NAND gate 340 is in order to produce this clock signal PLS, to determine this switching signal V SWSwitching frequency.One output play of this comparator 330 is coupled to one first input of this NAND gate 340.This output of this NAND gate 340 is in order to open and close this switch 328.Two inputs of one NAND gate 345 are connected to this output of this NAND gate 340 and an output of this comparator 335 respectively.This output of this NAND gate 345 is one second input that is connected to this NAND gate 340.This output of this NAND gate 345 is in order to open and close this switch 327.Therefore on capacitor 320, produce a serrated signal SAW.
Fig. 8 is the example oscillogram that illustrates this serrated signal SAW of the present invention and this clock signal PLS.T among the figure SWThe cycle of representing this serrated signal SAW.The frequency of this serrated signal SAW and this clock signal PLS is by this charging current I 325, this discharging current I 326, this capacitor 320 determines with numerical control capacitor 500.At this, this charging current I 325With this discharging current I 326Produced by circuit shown in Figure 9.
Fig. 9 is the circuit diagram that this current source 325 and current source 326 are described according to the embodiment of the invention.This current source 325 includes with this current source 326: amplifier 360, transistor 361, resistor 45 and current mirror.This current mirror is made up of 362~366 in transistor.In the embodiment of Fig. 9, resistor 45 is in order to the decision switching frequency.Amplifier 360 is according to an electric current I that is connected in the resistor 45 generation transistors 361 on the frequency setting end RT 361According to the preset ratio of this current mirror, this electric current I 361To go out this charging current I by a transistor 364 and a transistor 366 mirrors respectively 325With this discharging current I 326
Data signal groups N n~N 0Be to change data signal groups N according to the oscillator signal WAV of this two oscillator 200 n~N 0Change be that the switching frequency that sets with this first oscillator 300 is irrelevant.When by data signal groups N n~N 0When setting this numerical control capacitor 500, promptly accordingly modulation this switching signal V SWSwitching frequency.The frequency spectrum that switches energy promptly is unfolded, and has reduced the electromagnetic interference of power supply changeover device.Please refer to equation (2), changed the power output of power supply changeover device owing to the modulation of switching cycle T.Data signal groups N n~N 0More controlled this feedback signal V FBAttenuation rate, and then control this switching signal V SWON time T ONTherefore, compensating its variation by the switching frequency modulation, is certain value to keep power output and output voltage.
Though the present invention discloses as above with preferred embodiment; right its is not in order to limit the present invention; anyly have the knack of this operator; without departing from the spirit and scope of the present invention; when can doing a little change and retouching, so protection scope of the present invention is when looking accompanying being as the criterion that claim defines.

Claims (15)

1. the control circuit with frequency modulating in order to control a power supply changeover device, is characterized in that, this control circuit comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to produce a clock pulse signal to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the frequency of this clock signal of modulation;
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator includes a coding circuit to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is in order to controlling the switching frequency of this numerical control capacitor with this switching signal of modulation, and in order to control this digit-control resistance device to determine the attenuation rate of this feedback signal.
2. the control circuit with frequency modulating as claimed in claim 1 is characterized in that, wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being formed by many groups of indivedual regulating switch and modulation capacitors of connecting, and those regulating switch are to control its keying by this data signal groups.
3. the control circuit with frequency modulating as claimed in claim 1 is characterized in that, wherein this digit-control resistance device comprises:
Many group convert resistances are right, and those convert resistances are to being connected in parallel to each other, wherein those convert resistances to be by the attenuator switch of many groups of indivedual series connection and damping resistance device couple mutually form, those attenuator switch are to control its keying by this data signal groups.
4. the control circuit with frequency modulating as claimed in claim 1 is characterized in that, wherein this first oscillator comprises:
One charging current source is in order to produce a charging current;
One discharging current source is in order to produce a discharging current;
One oscillating capacitor is to be in parallel with this numerical control capacitor;
One charge switch is to be connected between this charging current source and this oscillating capacitor;
One discharge switch is connected between this discharging current source and this oscillating capacitor;
One first comparator, one first input is supplied by one first reference voltage, and one second input is to be connected to this oscillating capacitor;
One second comparator, one first input is to be connected to this oscillating capacitor, and one second input is supplied by one second reference voltage, and wherein this first reference voltage is to be higher than this second reference voltage;
One first lock, in order to produce this clock signal to determine the switching frequency of this switching signal, wherein one first of this first lock input is an output that is coupled to this first comparator, wherein one of this first lock output is in order to open and close this discharge switch; And
One second lock, its two inputs are connected to this output of this first lock and an output of this second comparator respectively, and an output of this second lock is one second input that is connected to this first lock, wherein one of this second lock output is in order to open and close this charge switch.
5. the control circuit with frequency modulating as claimed in claim 1 is characterized in that, wherein this coding circuit comprises:
A plurality of comparators, the positive input of those comparators are to be connected to this oscillator signal, and the negative input of those comparators is supplied by corresponding many group reference voltages respectively;
A plurality of flip-flops, the input of those flip-flops are the output that is coupled to those comparators respectively, and wherein the input of the clock pulse of those flip-flops is supplied by this clock signal; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
6. the control circuit with frequency modulating in order to control a power supply changeover device, is characterized in that, this control circuit comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation;
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator includes an analog-digital converter, in order to produce a data signal groups according to this oscillator signal; And
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; Wherein this data signal groups is controlled the resistance value of capacitance and this digit-control resistance device of this numerical control capacitor.
7. the control circuit with frequency modulating as claimed in claim 6 is characterized in that, wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being that regulating switch and modulation capacitors by many groups of indivedual series connection are formed, and open and close those regulating switch by this data signal groups.
8. the control circuit with frequency modulating as claimed in claim 6 is characterized in that, wherein this digit-control resistance device comprises:
Many group convert resistances are right, and those convert resistances are to being connected in parallel to each other, and wherein those convert resistances are to being that attenuator switch and damping resistance devices by many groups of indivedual series connection are formed, and open and close those attenuator switch by this data signal groups.
9. the control circuit with frequency modulating as claimed in claim 6 is characterized in that, wherein this first oscillator comprises:
One charging current source is in order to produce a charging current;
One discharging current source is in order to produce a discharging current;
One oscillating capacitor is in parallel with this numerical control capacitor;
One charge switch is connected between this charging current source and this oscillating capacitor;
One discharge switch is connected between this discharging current source and this oscillating capacitor;
One first comparator, one first input is provided by one first reference voltage, and one second input is to be connected to this oscillating capacitor;
One second comparator, one first input is connected to this oscillating capacitor, and one second input is provided by one second reference voltage, and wherein this first reference voltage is to be higher than this second reference voltage;
One first lock is coupled to this commutation circuit, and in order to determine the switching frequency of this switching signal, wherein one first of this first lock input is an output that is coupled to this first comparator, and wherein one of this first lock output is in order to open and close this discharge switch; And
One second lock, its two inputs are connected to this output of this first lock and an output of this second comparator respectively, and an output of this second lock is one second input that is connected to this first lock, wherein one of this second lock output is in order to open and close this charge switch.
10. the control circuit with frequency modulating as claimed in claim 6 is characterized in that, wherein this analog-digital converter comprises:
A plurality of comparators, the positive input of those comparators is supplied by this oscillator signal, and the negative input of those comparators is supplied by many groups reference voltage of correspondence respectively;
A plurality of flip-flops, the input of those flip-flops is coupled to the output of those comparators respectively, and wherein the clock pulse of those flip-flops input is that output by this first oscillator is provided; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
11. the control circuit with frequency modulating in order to control a power supply changeover device, is characterized in that, this controller comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One numerical control capacitor is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator comprises a coding circuit, in order to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is in order to control the capacitance of this numerical control capacitor.
12. the control circuit with frequency modulating as claimed in claim 11 is characterized in that, wherein this numerical control capacitor comprises:
Many group switch-capacitors are right, and those switch-capacitors are to being connected in parallel to each other, and wherein those switch-capacitors are to being that regulating switch and modulation capacitor by indivedual series connection formed, and open and close those regulating switch by this data signal groups.
13. the control circuit with frequency modulating as claimed in claim 11 is characterized in that, wherein this coding circuit comprises:
A plurality of comparators, the positive input of those comparators is supplied by this oscillator signal, and the negative input of those comparators is then provided by many groups reference voltage of its correspondence respectively;
A plurality of flip-flops, the input of those flip-flops are the output that is coupled to those comparators respectively, and wherein the input of the clock pulse of those flip-flops is the output that is connected to this first oscillator; And
One encoder is coupled to the output of those flip-flops, in order to produce this data signal groups.
14. the controller with frequency modulating in order to control a power supply changeover device, is characterized in that, this controller comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal;
One second oscillator is coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation; And
One digit-control resistance device is coupled to this feedback circuit, in order to this feedback signal that decays; Wherein this second oscillator is coupled to this digit-control resistance device, to control the resistance value of this digit-control resistance device.
15. the control circuit with frequency modulating in order to control a power supply changeover device, is characterized in that, this control circuit comprises:
One switches circuit, is coupled to a feedback circuit, switches signal to regulate an output of this power supply changeover device in order to produce one, and wherein this feedback circuit is this output that is coupled to this power supply changeover device, so that a feedback signal of this switching signal of control to be provided;
One first oscillator is coupled to this commutation circuit, in order to determine the switching frequency of this switching signal; And
One second oscillator, in order to produce an oscillator signal, wherein this second oscillator comprises a coding circuit, in order to produce a data signal groups according to this oscillator signal; Wherein this data signal groups is to be coupled to this first oscillator, in order to the switching frequency of this switching signal of modulation.
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CN102361396A (en) * 2011-09-02 2012-02-22 陕西源能微电子有限公司 Special pseudorandom sequence dither frequency control oscillator
CN102638159A (en) * 2012-05-09 2012-08-15 崇贸科技股份有限公司 Electromagnetic interference reducing circuit and electromagnetic interference reducing method
CN101741250B (en) * 2008-11-04 2012-10-03 友顺科技股份有限公司 Pulse width modulation control circuit reducing electromagnetic interference by frequency modulation of commercial power and method thereof
US8330735B2 (en) 2009-07-14 2012-12-11 Sonix Technology Co., Ltd. Capacitive touch circuit
CN101621291B (en) * 2009-08-05 2013-06-12 松翰科技股份有限公司 Capacitance type touch control induction circuit
RU2529871C1 (en) * 2013-06-18 2014-10-10 Общество с ограниченной ответственностью "Центр энергетических технологий" Arc current adaptive regulator
CN107749285A (en) * 2017-11-14 2018-03-02 深圳市华星光电技术有限公司 One kind electric leakage flow control circuit and control method

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101741250B (en) * 2008-11-04 2012-10-03 友顺科技股份有限公司 Pulse width modulation control circuit reducing electromagnetic interference by frequency modulation of commercial power and method thereof
US8330735B2 (en) 2009-07-14 2012-12-11 Sonix Technology Co., Ltd. Capacitive touch circuit
CN101621291B (en) * 2009-08-05 2013-06-12 松翰科技股份有限公司 Capacitance type touch control induction circuit
CN102361396A (en) * 2011-09-02 2012-02-22 陕西源能微电子有限公司 Special pseudorandom sequence dither frequency control oscillator
CN102361396B (en) * 2011-09-02 2013-11-20 陕西源能微电子有限公司 Special pseudorandom sequence dither frequency control oscillator
CN102638159A (en) * 2012-05-09 2012-08-15 崇贸科技股份有限公司 Electromagnetic interference reducing circuit and electromagnetic interference reducing method
RU2529871C1 (en) * 2013-06-18 2014-10-10 Общество с ограниченной ответственностью "Центр энергетических технологий" Arc current adaptive regulator
CN107749285A (en) * 2017-11-14 2018-03-02 深圳市华星光电技术有限公司 One kind electric leakage flow control circuit and control method

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