CN102983759A - Controller capable of controlling switch power supply to constantly output current and control method - Google Patents
Controller capable of controlling switch power supply to constantly output current and control method Download PDFInfo
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- CN102983759A CN102983759A CN2012105868134A CN201210586813A CN102983759A CN 102983759 A CN102983759 A CN 102983759A CN 2012105868134 A CN2012105868134 A CN 2012105868134A CN 201210586813 A CN201210586813 A CN 201210586813A CN 102983759 A CN102983759 A CN 102983759A
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Abstract
The invention discloses a controller capable of controlling switch power supply to constantly output current and a control method. The controller comprises a zero-cross detection circuit, a charge-discharge balancing circuit, a first comparator, a second comparator and a logic control circuit that is used for generating a driving signal to control connection and disconnection of a switch tube of a switch power supply. The charge-discharge balancing circuit comprises a switch sequential control circuit, a charge-discharge current balanced structure circuit and a capacitor, wherein the charge-discharge current balanced structure circuit comprises a current balancing module that has a current regulating phase and a charge-discharge phase; the current balancing module can regulate the current at the current regulating phase to generate equal first current and second current, and charge the capacitor by the first current and discharge the capacitor by the second current at the charge-discharge phase.
Description
Technical field
The present invention relates to Switching Power Supply, relate in particular to controller, the control method of control switch constant electrical power output current and the Switching Power Supply that comprises this controller.
Background technology
Switching Power Supply is to keep a kind of power supply of burning voltage or electric current output by the turn-on and turn-off of control switch pipe (such as transistor, field effect transistor, controllable silicon thyratron etc.).Compare with traditional linear power supply, the efficient of Switching Power Supply is higher, loss and heating still less, therefore in electronic technology, be with a wide range of applications.
Traditional inverse-excitation type constant-current switch power source generally includes controller, transformer and switching tube, wherein the former limit winding of transformer is connected with switching tube, controller can be controlled these switching tube alternately turn-on and turn-off the input energy on the transformer primary side winding is passed to the secondary winding of transformer, make this Switching Power Supply be operated in constant current state, thereby stably provide output current wave.The switch power controller of prior art uses different fixed current sources that capacitor is carried out charging and discharging, but when charging and discharging currents has change, will cause the change of switch power supply output current, thereby be difficult to guarantee that switching power circuit has good consistency.
This area needs to control better and to provide the Switching Power Supply of constant current output.
Summary of the invention
The technical problem to be solved in the present invention provides a kind of Switching Power Supply.Particularly, controller and control method that the present invention aims to provide a kind of constant current output Switching Power Supply and controls its constant output current, thus improve the output-consistence of Switching Power Supply.
For solving the problems of the technologies described above, the invention provides a kind of controller for Switching Power Supply, this Switching Power Supply comprises fly-wheel diode, switching tube and is coupled to the sampling resistor of switching tube, this controller can comprise: zero cross detection circuit, for detection of the ON time of this fly-wheel diode to produce the ON time signal; Discharge and recharge balancing circuitry, discharge and recharge signal under the control of this ON time signal, producing; The first comparator is used for that this is discharged and recharged signal and the first reference voltage makes comparisons to produce the first comparative result; The second comparator is used for and will makes comparisons to produce the second comparative result via sampled voltage signal and the second reference voltage that this sampling resistor produces; And logic control circuit, be used for producing the driving signal according to this ON time signal, this first comparative result and this second comparative result, to control the turn-on and turn-off of this switching tube.
This discharges and recharges balancing circuitry and can comprise: the switching sequence control circuit is used for producing the switching sequence control signal according to this ON time signal; Charging and discharging currents balanced structure circuit, it is coupled to this switching sequence control circuit; And capacitor, its first end is coupled to this charging and discharging currents balanced structure circuit and its second end coupling grounding, this charging and discharging currents balanced structure circuit discharges and recharges this capacitor under the control of this switching sequence control signal, and this discharges and recharges balancing circuitry provides this to discharge and recharge signal at the first end of this capacitor.
This charging and discharging currents balanced structure circuit can comprise current balance module, this current balance module has electric current to be regulated the stage and discharges and recharges the stage, this current balance module carries out electric current in the electric current adjusting stage and regulates to produce the first equal electric current and the second electric current, and uses the first electric current that this capacitor is charged and use the second electric current to this discharging capacitors in the stage of discharging and recharging.
In one embodiment, this current balance module is mirror current source, this mirror current source can comprise the first transistor and transistor seconds, the grid of the first transistor is coupled to the grid of transistor seconds, the first electric current the first transistor and the second electric current transistor seconds of flowing through of flowing through, this current balance module is regulated the grid voltage of the first transistor and transistor seconds with the first electric current and the second difference between currents in the electric current adjusting stage, thereby regulate the conducting resistance of the first transistor and transistor seconds, this first electric current of the first transistor of flowing through is equated with this second electric current of the transistor seconds of flowing through.This mirror current source also can comprise inverter, and being used for will be by the voltage coupling of the first electric current and the generation of the second difference between currents grid to the first transistor and transistor seconds.
In one embodiment, this charging and discharging currents balanced structure circuit can comprise a current balance module and comprise fixedly mirror current source, uses fixedly when electric current is regulated the stage when this current balance module is in that mirror current source discharges and recharges this capacitor.
In one embodiment, this charging and discharging currents balanced structure circuit can comprise at least two current balance modules, in each cycle of this ON time signal, this switching sequence control signal makes a current balance module in these at least two current balance modules enter the stage of discharging and recharging and makes other current balance module enter electric current regulates the stage, thereby these at least two current balance module alternatelies discharge and recharge this capacitor.
In one embodiment, this switching sequence control circuit comprises frequency divider and gate circuit, is used for producing the switching sequence control signal according to the ON time signal.
In one embodiment, current balance module uses the first electric current that this capacitor is charged in the stage that discharges and recharges when this fly-wheel diode of ON time signal designation is cut-off, and uses the second electric current to this discharging capacitors when ON time signal designation fly-wheel diode is conducting.
In one embodiment, this logic control circuit can comprise: the first rest-set flip-flop, and its set termination is received the ON time signal, and its reset terminal receives the first comparative result; Inverter, its input is coupled to the output of the first rest-set flip-flop; The second rest-set flip-flop, its set end is coupled to the output of this inverter, and its reset terminal receives the second comparative result; And driver, its input is coupled to the output of the second rest-set flip-flop, and its output produces this driving signal.
The present invention also provides the Switching Power Supply that comprises aforesaid controller.This Switching Power Supply also can comprise: transformer, and the Same Name of Ends of its former limit winding receives input signal, and the different name end of its auxiliary winding is coupled to the input of zero cross detection circuit, the Same Name of Ends coupling grounding of this auxiliary winding; Switching tube, its drain coupled are to the different name end of the former limit winding of this transformer, and its grid receives this driving signal that this controller produces, and its source electrode is via the sampling resistor coupling grounding; And fly-wheel diode, its positive pole is coupled to the different name end of the secondary winding of this transformer, and its negative pole is coupled to Same Name of Ends and the ground connection of secondary winding via output capacitor, and wherein this Switching Power Supply provides output current to the load in parallel with output capacitor.
The present invention also provides a kind of method for the control switch power supply, this Switching Power Supply comprises fly-wheel diode, switching tube and is coupled to the sampling resistor of this switching tube that the method can comprise: detect the ON time of this fly-wheel diode to produce the ON time signal; Under the control of this ON time signal, produce and discharge and recharge signal; This is discharged and recharged signal and the first reference voltage makes comparisons to produce the first comparative result; To make comparisons to produce the second comparative result via sampled voltage signal and the second reference voltage that sampling resistor produces; And according to this ON time signal, the first comparative result and the second comparative result generation driving signal, to control the turn-on and turn-off of this switching tube.
In one embodiment, produce and to discharge and recharge signal and can comprise: produce the switching sequence control signal according to the ON time signal; And with this switching sequence control signal control charging and discharging currents balanced structure circuit capacitor is discharged and recharged, the first end of this capacitor is coupled to this charging and discharging currents balanced structure circuit and its second end coupling grounding, and wherein the first end at this capacitor provides this to discharge and recharge signal.
In one embodiment, this charging and discharging currents balanced structure circuit can comprise current balance module, this switching sequence control signal is controlled this current balance module and is entered electric current adjusting stage or the stage of discharging and recharging, this current balance module carries out electric current in the electric current adjusting stage and regulates to produce the first equal electric current and the second electric current, and uses the first electric current that this capacitor is charged and use the second electric current to this discharging capacitors in the stage of discharging and recharging.
In one embodiment, this current balance module is mirror current source, this mirror current source comprises the first transistor and transistor seconds, the grid of the first transistor is coupled to the grid of transistor seconds, the first electric current the first transistor and the second electric current transistor seconds of flowing through of flowing through, wherein carrying out the electric current adjusting comprises: the grid voltage of regulating the first transistor and transistor seconds with the first electric current and the second difference between currents, thereby regulate the conducting resistance of the first transistor and transistor seconds, the first electric current of the first transistor of flowing through is equated with the second electric current of the transistor seconds of flowing through.
In one embodiment, the method also can comprise: use fixedly when electric current is regulated the stage when this current balance module is in that mirror current source discharges and recharges this capacitor.
In one embodiment, this charging and discharging currents balanced structure circuit comprises at least two current balance modules, the method also can comprise: in each cycle of ON time signal, this switching sequence control signal makes a current balance module in these at least two current balance modules enter the stage of discharging and recharging and makes other current balance module enter electric current regulates the stage, thereby these at least two current balance module alternatelies discharge and recharge this capacitor.
In one embodiment, the grid voltage of regulating the first transistor and transistor seconds comprises: will be by the voltage coupling of the first electric current and the generation of the second difference between currents grid to the first transistor and transistor seconds.
In one embodiment, the method can comprise: discharging and recharging the stage, when ON time signal designation fly-wheel diode is cut-off, this current balance module uses the first electric current that this capacitor is charged, and when ON time signal designation fly-wheel diode was conducting, this current balance module used the second electric current to this discharging capacitors.
Compared with prior art, the present invention has the following advantages: the controller of control switch constant electrical power output current of the present invention can accurately be controlled the ratio of charging and discharging currents in the course of the work, eliminated owing to the output-consistence problem that charging and discharging currents does not mate and the reasons such as current error that pass to produce in time cause, and especially be fit to the charging current occasion identical with discharging current.
Description of drawings
Fig. 1 illustrates a kind of circuit diagram of traditional Switching Power Supply;
Fig. 2 illustrates the signal waveforms of the Switching Power Supply of Fig. 1;
Fig. 3 illustrates the according to an embodiment of the invention circuit diagram of Switching Power Supply;
Fig. 4 illustrates the according to an embodiment of the invention circuit diagram of switching sequence control circuit;
Fig. 5 illustrates the signal waveforms of the switching sequence control circuit of Fig. 4;
Fig. 6 A illustrates the according to an embodiment of the invention circuit diagram of charging and discharging currents balancing circuitry;
Fig. 6 B illustrates the according to another embodiment of the present invention circuit diagram of charging and discharging currents balancing circuitry;
Fig. 7 illustrates according to an embodiment of the invention adjustable mirror image current source structure.
Embodiment
The invention will be further described below in conjunction with specific embodiments and the drawings, but it will be apparent to one skilled in the art that the following description and drawings only are exemplary, and should not limit protection scope of the present invention.The element that has same or similar Reference numeral in the accompanying drawing can operate similarly.
Fig. 1 illustrates a kind of traditional inverse-excitation type constant current driving switch power supply.This Switching Power Supply mainly comprises: alternating current source (AC) 102, rectification circuit 101, input capacitor (Cin) 103, isolating transformer (T) 105, switching tube 106, fly-wheel diode (D1) 107, output capacitor (Cbulk) 108, Switching Power Supply constant-current controller 100 and sampling resistor Rs etc.Isolating transformer 105 comprises former limit winding L 1, secondary winding L 2 and auxiliary winding L 3.The former limit winding L 1 of transformer 105 is via switching tube 106 and sampling resistor Rs ground connection; Secondary winding L 2 provides electric current output via fly-wheel diode 107 and output capacitor 108; And auxiliary winding L 3 output feedback signal FB are to controller 100.Controller 100 produces driving signal GD according to the sampled voltage Vcs at feedback signal FB and sampling resistor Rs two ends, the turn-on and turn-off that are used for control switch pipe 106, thereby by isolating transformer 105 the input energy is passed to output, produces stable output current wave at output.
Switching Power Supply constant-current controller 100 can comprise: zero cross detection circuit 129, discharge and recharge balancing circuitry 200, comparator 121, logic control circuit 120, comparator 124 and lead-edge-blanking circuit (LEB) 125.As example, discharge and recharge balancing circuitry 200 and can comprise current source I1 and current source I2, inverter 104, switch S 1 and S2 and capacitor C1.Logic control circuit 120 can comprise rest-set flip-flop 122, inverter 123, rest-set flip-flop 126 and driver 128.
At work, the ac input signal AC that alternating current source 102 produces is through rectification circuit 101 rectifications and through producing input signal Vin after input capacitor 103 filtering, and it transfers to the Same Name of Ends of the former limit winding L 1 of isolating transformer 105.When switching tube 106 conducting, the Same Name of Ends voltage of the former limit winding L 1 of transformer 105 is higher than the different name terminal voltage, and fly-wheel diode 107 is in cut-off state, thus in the winding L 1 of former limit storage power.Switching tube 106 closes has no progeny, and isolating transformer 105 instead swashs, fly-wheel diode 107 conductings, and the output energy is to output, and this moment, the induced voltage (being feedback signal FB) of auxiliary winding L 3 was positive voltage.The electric current that flows through fly-wheel diode 107 constantly reduces, until vanishing, the feedback signal FB that this moment, auxiliary winding L 3 was sensed serves as reasons and just becomes negatively, and next parasitic oscillation occurs.Therefore, can detect by auxiliary winding L 3 time of afterflow of fly-wheel diode 107, this function can be finished by zero cross detection circuit 129.
Zero cross detection circuit 129 receives the feedback signal FB of auxiliary winding L 3 outputs, for detection of the ON time (that is, time of afterflow) of the fly-wheel diode 107 of this Switching Power Supply, thereby produces ON time signal Tdemag.Discharge and recharge balancing circuitry 200 under the control of ON time signal Tdemag, produce discharge and recharge the voltage that signal Vc(is capacitor C1 two ends).When ON time signal Tdemag was high level, switch S 1 disconnected and switch S 2 conductings, and capacitor C1 discharges to ground through switch S 2 and current source I2; When ON time signal Tdemag was low level, capacitor C1 was charged through switch S 1 by current source I1.
The first comparator 121 will discharge and recharge signal Vc and make comparisons to produce the first comparative result with the first reference voltage V refa that presets.The sampled voltage Vcs at the sampling resistor Rs two ends that the second comparator 124 will receive via lead-edge-blanking circuit 125 and the second default reference voltage V refb make comparisons to produce the second comparative result.Logic control circuit 120 produces according to ON time signal Tdemag, the first comparative result and the second comparative result and drives signal GD, drives the turn-on and turn-off that signal GD is used for the switching tube 106 of this Switching Power Supply of control.
Fig. 2 is the signal timing diagram of circuit shown in Figure 1 under the constant current operating state.The workflow of the Switching Power Supply shown in Fig. 1 is described below in conjunction with Fig. 2.Suppose that this Switching Power Supply had entered the constant current operating state before time t1 and switching tube 106 is in conducting state.
At time t1, switching tube 106 turn-offs, and isolating transformer 105 instead swashs, thus so fly-wheel diode 107 conductings and detected the ON time signal Tdemag that produces high level by zero cross detection circuit 129.After this electric current that flows through fly-wheel diode 107 constantly reduces, until in time t2 vanishing.During fly-wheel diode 107 ON time, (it is the degaussing time of isolating transformer 105, t1 to t2), ON time signal Tdemag(for example, high level) control discharges and recharges switch S 2 conductings and switch S 1 disconnection of balancing circuitry 200, thereby capacitor C1 discharges to ground through switch S 2, discharging current is provided by current source I2, until discharge into Vc minimum point voltage when time t2.
At time t2, the time of afterflow of fly-wheel diode 107 finishes, and ON time signal Tdemag becomes low level, so that switch S 1 conducting and switch S 2 disconnect, current source I1 provides charging current to charge via 1 couple of capacitor C1 of switch S, and Vc increases gradually.
At time t3, as Vc during greater than Vrefa, logic control circuit 120 produces and for example drives signal GD(, high level accordingly), this driving signal GD makes switching tube 106 conductings.After switching tube 106 conductings, it is large that the electric current of the former limit winding L 1 of isolating transformer 105 becomes, auxiliary winding L 3 induced voltages (being feedback voltage FB) are negative voltage, and the electric current on the former limit winding L 1 obtains sampled voltage Vcs by sampling resistor Rs sampling, and sampled voltage Vcs also increases gradually.
At time t4, when sampled voltage Vcs reached reference voltage V refb, the output switching activity of comparator 124 became low level through rest-set flip-flop 126, driver 128 so that drive signal GD, thus on-off switching tube 106.Before switching tube 106 turn-offed, current source I1 charged to capacitor C1 always.Can find out, the length of the ON time of switching tube 106, (on the former limit winding L 1) inductance peak current of being determined by reference voltage V refb determines, it is very little or be transfused to voltage compensation to suppose to open delay, then the inductance peak current is Vrefb/Rs, wherein Vrefb is the magnitude of voltage of reference voltage V refb, and Rs is the resistance value of sampling resistor Rs.
Have no progeny in switching tube 106 passes, fly-wheel diode 107 conductings, the as above described process of reference time t1 to t4 that circulates, thus reach the purpose of controlling constant current.
When stablizing, being in the constant current loop circuit state at circuit, Vc level (being the voltage at capacitor C1 two ends) is triangular wave, in the up and down fluctuation of reference voltage V refa.The balance that discharges and recharges of capacitor C1 has following relation:
I
1·（T-T
demag）=I
2·T
demag
Wherein T is switch periods, T
DemagBe the degaussing time (being the time of afterflow of fly-wheel diode 107) of transformer secondary winding, I
1And I
2Be respectively current source I1 among Fig. 1 and the output current of I2.
That is, constant current duty ratio is:
And to reverse excitation circuit:
Wherein: n is the turn ratio of transformer primary secondary winding, I
PkThe peak current of former limit winding, I
OutAverage output current for transformer.
As from the foregoing, as long as guarantee to discharge and recharge balance, guarantee that simultaneously peak current is constant, just can guarantee the constant-current characteristics of circuit.
Yet, because the peak current of output current and transformer primary side winding L 1, the ratio of charging and discharging currents that discharges and recharges balancing circuitry 200 are relevant, therefore the ratio when charging and discharging currents slightly has change, will cause the change of output current, thereby cause being difficult to guarantee that switching power circuit has good consistency.
Fig. 3 illustrates the according to an embodiment of the invention circuit structure of improved Switching Power Supply, and it can strictly control the ratio of charging and discharging currents, has avoided can not accurately controlling and affecting the switching power circuit consistency owing to the ratio of charging and discharging currents.In addition, this improved Switching Power Supply also is particularly useful for the identical occasion of charging and discharging currents, can eliminate owing to charging and discharging currents does not mate the consistency problem that causes.For simplicity's sake, element, connection and the operation identical with Fig. 1 will be omitted or only sketch in the switch power supply line structure of Fig. 3.
With reference to figure 3, this Switching Power Supply mainly comprises: alternating current source 102, rectification circuit 101(for example, rectifier bridge), input capacitor 103, isolating transformer 105, fly-wheel diode 107, output capacitor 108, controller 30, switching tube 306 and sampling resistor Rs etc.Switching tube 306 can be any switch module that is applicable to Switching Power Supply, such as transistor, field effect transistor, controllable silicon thyratron etc.This Switching Power Supply can comprise different or other element, and those skilled in the art can design according to system's needs, for for simplicity not at this detailed description.The ac input signal AC that alternating current source 102 produces produces input signal Vin through rectification circuit 101 rectifications and after input capacitor 103 filtering.The Same Name of Ends of the former limit winding L 1 of transformer 105 is used for receiving input Vin, and its different name end is coupled to the drain electrode of switching tube 306.The grid of switching tube 306 receives the driving signal GD that is produced by controller 30, and its source electrode is via sampling resistor Rs ground connection, wherein the electric current (for example, peak current) of the former limit winding L 1 of sampling resistor Rs sampling transformer 105.The Same Name of Ends of the secondary winding L 2 of transformer 105 is coupled to an end and the ground connection of output capacitor 108, and the different name end of secondary winding L 2 is coupled to the positive pole of fly-wheel diode 107, and the negative pole of fly-wheel diode 107 is coupled to the other end of output capacitor 108.Transformer 105 provides output current by secondary winding L 2 thus, and to reduce ripple, load (for example, load LED etc.) can be in parallel to receive this output current with output capacitor 108 via output capacitor 108 filtering for this output current.The Same Name of Ends coupling grounding of the auxiliary winding L 3 of transformer 105, and its different name end output feedback signal FB is to controller 30.Controller 30 produces according to feedback signal FB and via the sampled voltage signal Vcs that sampling resistor Rs detects and drives signal GD, is used for the turn-on and turn-off of control switch pipe 306.Isolating transformer 105, fly-wheel diode 107 and switching tube 306 etc. can such as above with reference to the isolating transformer 105 among Fig. 1, fly-wheel diode 107 and switching tube 106 description ground work, and under the control of controller 30, be operated in the constant current loop circuit state.For example, the output current of fly-wheel diode 107 can be triangular wave, and the average current in each cycle keeps constant.
Below describe structure and the operation of controller 30 in detail.
In one embodiment, controller 30 can comprise: zero cross detection circuit 329, discharge and recharge balancing circuitry 300, the first comparator 321, logic control circuit 320, the second comparator 324 and lead-edge-blanking circuit (LEB) 325.
Zero cross detection circuit 329 receives the feedback signal FB by auxiliary winding L 3 outputs of transformer 105, and the ON time for detection of the fly-wheel diode 107 of this Switching Power Supply produces ON time signal Tdemag.As an example, ON time signal Tdemag is 107 conductings of high level indication fly-wheel diode, and be 107 cut-offs of low level indication fly-wheel diode, vice versa, perhaps also can use other suitable signal level to indicate respectively conducting and the cut-off of fly-wheel diode 107.
Discharging and recharging balancing circuitry 300 can comprise: switching sequence control circuit 302, charging and discharging currents balanced structure circuit 303 and capacitor C1, wherein switching sequence control circuit 302 is used for producing the switching sequence control signal according to ON time signal Tdemag, 303 couples of capacitor C1 discharge and recharge with control charging and discharging currents balanced structure circuit, thereby discharge and recharge signal Vc in the first end generation of capacitor C1.Charging and discharging currents balanced structure circuit 303 can comprise at least one current balance module, such as the mirror current source of being realized by transistor circuit, each mirror current source can produce separately the first equal electric current and the second electric current and periodically enter electric current regulates the stage to guarantee that its first electric current and the second electric current are equal.For example, the first electric current flow through transistor seconds of this mirror current source of the first transistor of mirror current source and the second electric current of flowing through, the first and second transistorized grids are coupled, this mirror current source is regulated the grid voltage of the first transistor and transistor seconds with the first electric current and the second difference between currents in the electric current adjusting stage, thereby regulate the conducting resistance of the first transistor and transistor seconds, this first electric current of the first transistor of flowing through is equated with this second electric current of the transistor seconds of flowing through.In cycle, switching sequence control circuit 302 makes one of them current balance module discharge and recharge capacitor C1 at each ON time signal Tdemag.For example, at fly-wheel diode 107 conduction periods (for example, ON time signal Tdemag is high level), this current balance module uses its second electric current that capacitor C1 is discharged; Fly-wheel diode 107 blocking intervals (for example, ON time signal Tdemag is low level), this current balance module uses its first electric current that capacitor C1 is charged.Because used the image current that equates during each discharges and recharges, just can accurately control the charging and discharging currents ratio is 1:1, thereby improve the consistency of output current.
The first comparator 321 first input end receive discharge and recharge balancing circuitry 300 outputs discharge and recharge signal Vc, receive the first default reference voltage V refa at the second input, and produce the first comparative result at output.The sampled voltage Vcs(that the second comparator 324 receives sampling resistor Rs two ends via lead-edge-blanking circuit 325 at first input end for example, crest voltage), receive the second default reference voltage V refb at the second input, and produce the second comparative result at output.
Logic control circuit 320 can comprise rest-set flip-flop 322, inverter 323, rest-set flip-flop 326 and driver 328.The set end (S) of rest-set flip-flop 322 receives the ON time signal Tdemag by zero cross detection circuit 329 outputs, and its reset terminal (R) receives the first comparative result by 321 outputs of the first comparator.The output of rest-set flip-flop 322 is coupled to the set end of rest-set flip-flop 326 via inverter 323, and the reset terminal of rest-set flip-flop 326 receives the second comparative result by 324 outputs of the second comparator.Driver 328 receives the output of rest-set flip-flop 326 and produces driving signal GD at its output.Therefore, logic control circuit 320 produces according to ON time signal Tdemag, the first comparative result and the second comparative result and drives signal GD, with the turn-on and turn-off of the switching tube 306 that is used for the control switch power supply.As an example, drive when signal GD is high level and control switching tube 306 conductings, when being low level, signal GD controls switching tube 306 shutoffs and drive, and vice versa.Those skilled in the art are to be understood that, logic control circuit 320 can have the circuit structure of other replacement, as long as can produce the corresponding turn-on and turn-off that signal GD comes the switching tube 306 of control switch power supply that suitably drive according to ON time signal Tdemag, the first comparative result and the second comparative result.
The sequential chart of the Switching Power Supply shown in Fig. 3 can be similar to the sequential chart shown in Fig. 2, but signal period and signal level can have different value.
Fig. 4 illustrates the according to an embodiment of the invention circuit diagram of switching sequence control circuit 302, and Fig. 5 illustrates the signal waveforms of circuit shown in Figure 4.In this embodiment, switching sequence control circuit 302 for example can comprise frequency divider 401, inverter 402, a plurality of gate circuit 403-406(, NAND gate).Frequency divider 401 receives ON time signal Tdemag, and the output frequency division signal is to gate circuit 403-406, thereby produces a plurality of switching sequence control signals, for example S11, S12, S13, S14, S21, S22, S23, S24.Fig. 4 and Fig. 5 have provided the two divided-frequency signal as example, but can use as required any other n fractional frequency signal in various realizations, and wherein n is positive integer, for example 4 frequency divisions, 6 frequency divisions etc.In addition, it will be appreciated by those skilled in the art that, frequency divider 401 shown in Fig. 4 and Fig. 5, inverter 402, gate circuit 403-406 illustrate as example, in concrete practice, can produce required switching sequence control signal with more or less frequency divider 401, inverter 402, gate circuit 403-406 or different circuit structures.
Fig. 6 A shows the according to an embodiment of the invention circuit diagram of charging and discharging currents balancing circuitry 303.For ease of describing, each switch among Fig. 6 A is controlled by the switching sequence control signal S11 to S24 that has same numeral among Fig. 4 and Fig. 5.In this embodiment, charging and discharging currents balancing circuitry 300 comprises two current balance modules 601 and 602, two mirror current sources for example, and they are coupled to the first end Vc of capacitor C1 as shown in Figure 3 by switching circuit.Wherein current balance module 601 is for generation of electric current I 11=I12, and current balance module 602 is for generation of electric current I 21=I22, and wherein I11 and I12 can equal or be not equal to I21 and I22.
In one embodiment, current balance module 601 can comprise PMOS pipe MP11 and MP12, NMOS pipe MN11 and MN12, inverter N11 and a plurality of switch S 11, S12, S13, S14.Vb is an inner bias voltage, and it offers PMOS pipe MP12 to produce bias current.Equally, Va is an inner bias voltage, and it offers NMOS pipe MN12 to produce bias current.Va and Vb can be the mirror image bias voltages that is produced by current mirror.Similarly, current balance module 602 can comprise PMOS pipe MP21 and MP22, NMOS pipe MN21 and MN22, inverter N21 and a plurality of switch S 21, S22, S23, S24.The current difference of the metal-oxide-semiconductor that causes in order to reduce drain terminal voltage difference, metal-oxide-semiconductor MP12, MN12, MP22, MN22 can be replaced by the mirror current source of accordion structure, according to an embodiment of the invention adjustable mirror image current source structure as shown in Figure 7.Be simple meter, take MP12 as example, with reference to figure 7, MP12 can be folded by two PMOS pipes MP12a, MP12b and consist of, bias voltage Vb becomes Vba, Vbb, these voltages are produced by bias current Ibias resistance R 701, PMOS pipe MP13b, the PMOS pipe MP13a that flows through, and can come by the gate voltage of regulating MP11 the size of regulation output electric current I 11.Those skilled in the art can adopt similar replacing structure to other metal-oxide-semiconductor among Fig. 6 A (for example, MN12, MP22, MN22), to improve circuit stability.It will be appreciated by those skilled in the art that each current balance module can use various suitable circuit structures (for example, mirror current source) to produce separately two equal electric currents, is not limited to the embodiment shown in Fig. 6 A.
Describe the operation of the charging and discharging currents balancing circuitry 303 shown in Fig. 6 A referring to Fig. 5, suppose before time t1, to have entered the constant current operating state.
During time t1 to t2, switch S 13 conductings and switch S 14 disconnect, and current balance module 601 is in the stage of discharging and recharging and is coupled to the first end Vc of capacitor C1, thereby with identical electric current I 11 and I12 capacitor C1 is discharged and recharged.With reference to figure 3 and Fig. 5, during this stage, at time t1, switching tube 306 turn-offs, isolating transformer 105 instead swashs, fly-wheel diode 107 conductings, and ON time signal Tdemag becomes high level, thereby switch S 11 disconnects and switch S 12 conductings, and current balance module 601 is by 12 pairs of capacitor C1 discharges of electric current I.After this, the electric current of fly-wheel diode 107 constantly reduces until vanishing, this moment, fly-wheel diode 107 was in cut-off state, thereby ON time signal Tdemag becomes low level, therefore switch S 11 conductings and switch S 12 disconnect, current balance module 601 is by 11 pairs of capacitor C1 chargings of electric current I, so that the voltage Vc of capacitor C1 increases.When the voltage Vc of capacitor C1 surpasses threshold voltage Vrefa, driving signal GD control switch pipe 306 conductings of logic control circuit 320 outputs, thus sampled voltage Vcs increases gradually.When at time t2, when voltage Vcs surpassed threshold voltage Vrefb, the driving signal GD control switch pipe 306 of logic control circuit 320 outputs turn-offed.
Obviously, (t1 to t2) is identical with I12 by the charging and discharging currents I11 that current balance module 601 provides during this discharges and recharges the stage, has realized the accurate control to the charging and discharging currents ratio.
During time t2 to t3, switch S 13 disconnects and the S14 conducting, and current balance module 601 is in electric current and regulates the stage.In this stage, all the time conducting of switch S 11, S12 is also passed through switch S 14 formation closed circuits.If this moment electric current I 11 and electric current I 12 different (for example because at work in time passing produced error), then electric current I 11 produces voltage with the difference of electric current I 12 at the input of inverter N11, so that can regulate by the closed circuit in the current balance module 601 gate voltage of MP11, MN11, thereby regulate the conducting resistance of MP11, MN11, force the electric current I 11 of the MP12 that flows through identical with the electric current I 12 of the MN12 that flows through.Other way of also can sampling is carried out the electric current adjusting so that two electric currents of current balance module 601 equate.
Electric current at current balance module 601 is regulated the stage (t2 to t3), comes capacitor C1 is discharged and recharged control with current balance module 602.Current balance module 602 is similar with the operating principle of current balance module 601, but it is in the electric current adjusting stage at time t1 to t2, and uses electric current I 21=I22 that capacitor C1 is discharged and recharged at time t2 to t3.
As described above, current balance module 601 and current balance module 602 discharge and recharge capacitor C1 in turn, and when one of them current balance module discharged and recharged, another current balance module self carries out electric current to be regulated.Namely regulate the stage at the electric current of current balance module 601, utilize electric current I 11=I12 that capacitor C1 is discharged and recharged by current balance module 602, and regulate the stage at the electric current of current balance module 602, current balance module 601 utilizes electric current I 21=I22 that capacitor C1 is discharged and recharged.Like this, discharge and recharge the cycle (ON time signal Tdemag cycle) at any, just can accurately control the charging and discharging currents ratio is 1:1, thereby has improved the consistency of output current.Simultaneously, each current balance module periodically carries out electric current to be regulated, and has effectively proofreaied and correct the current error that produces at work, has guaranteed to produce two equal electric currents so that capacitor C1 is discharged and recharged.
It is to set according to time of 1:1 that two current balance modules 601,602 that Fig. 4 and Fig. 5 provide take turns to operate.Those skilled in the art can understand, can be that current balance module 601,602 is set other any time scales that discharges and recharges by suitable switching sequence control circuit, for example current balance module 601 discharges and recharges in the cycle at a plurality of Tdemag continuously, then enter electric current and regulate the stage and discharged and recharged in the cycle at one or continuous a plurality of Tdemag by current balance module 602, can reach equally accurate control charging and discharging currents ratio.
Fig. 6 B shows the according to another embodiment of the present invention circuit diagram of charging and discharging currents balancing circuitry 303.Charging and discharging currents balancing circuitry 303 can comprise aforesaid current balance module 601 and can comprise fixedly mirror current source 603.In this embodiment, only can adopt a current balance module 601 to improve the precision of charging and discharging currents ratio, wherein current balance module 601 can be controlled constantly in the cycle at a plurality of continuous T demag capacitor C1 is discharged and recharged.In this case, current balance module 601 can enter primary current every certain Tdemag cycle and regulate the stage, and comes capacitor C1 is discharged and recharged with additional fixedly mirror current source 603 in this electric current adjusting stage.Fixedly mirror current source 603 can adopt any current source technology known in the art to realize producing basic two electric current I 21 that equate and I22, even can be two current sources independently.For example, fixedly mirror current source 603 can comprise PMOS pipe MP22, NMOS pipe MN22 and a plurality of switch S 21, S22, S23.When current balance module 601 was in electric current and regulates the stage, fixedly mirror current source 603 was connected to capacitor C1 by switch S 23 and discharges and recharges.Particularly, fixedly mirror current source 603 available current I22 come to come capacitor C1 is charged to capacitor C1 discharge and with electric current I21.In one embodiment, this electric current adjusting stage can be arranged to have the short period.For example, 100 input ON time signal Tdemag cycles can be used as the stage that 601 couples of capacitor C1 of current balance module discharge and recharge, ensuing 1 Tdemag cycle can be used as electric current and regulates the stage, and using fixedly in this electric current adjusting stage, 603 couples of capacitor C1 of mirror current source discharge and recharge.It also is possible that the stage that discharges and recharges of any other ratio and electric current are regulated the stage.The electric current of current balance module 601 is regulated the stage and discharged and recharged the control in stage can be by suitable switching sequence control circuit control.When current balance module 601 is in electric current and regulates the stage, switching sequence control circuit 302 switch S 13 is disconnected and fixedly mirror current source 603 be coupled to Vc so that C1 is discharged and recharged.Be in when discharging and recharging the stage at current balance module 601, switching sequence control circuit 302 disconnects switch S 14 and makes switch S 13 conductings to be discharged and recharged by 601 couples of C1 of current balance module as described above.Significantly reduce in this case circuit complexity and cost, and still can reach high-precision charging and discharging currents ratio.
In addition, can adopt two above current balance modules in turn capacitor C1 to be discharged and recharged, in any Tdemag the cycle, one of them current balance module discharges and recharges (when Tdemag is high level discharge and charge) to capacitor C1 when Tdemag is low level.For example, when a current balance module is in the electric current adjusting during stage, by another current balance module capacitor C1 is discharged and recharged, and be in when discharging and recharging the stage when a current balance module, other current balance module is in the free time or electric current is regulated the stage.The operation of a plurality of current balance modules can be similarly by 302 controls of switching sequence control circuit.
It will be appreciated by those skilled in the art that the various signal levels that illustrate are exemplary, can make amendment as required herein in concrete practice.Although the present invention has described better exemplary embodiment in detail, these embodiment are intended to limit the present invention.Protection scope of the present invention should be as the criterion with claims.Those skilled in the art can carry out possible change and modification to each embodiment without departing from the spirit and scope of the present invention, and these changes and modification all drop within protection scope of the present invention.
Claims (15)
1. controller that is used for Switching Power Supply, described Switching Power Supply comprises fly-wheel diode, switching tube and is coupled to the sampling resistor of described switching tube that described controller comprises:
Zero cross detection circuit, for detection of the ON time of described fly-wheel diode to produce the ON time signal;
Discharge and recharge balancing circuitry, discharge and recharge signal under the control of described ON time signal, producing;
The first comparator is used for discharging and recharging signal and the first reference voltage makes comparisons to produce the first comparative result with described;
The second comparator is used for and will makes comparisons to produce the second comparative result via sampled voltage signal and the second reference voltage that described sampling resistor produces; And
Logic control circuit is used for producing according to described ON time signal, described the first comparative result and described the second comparative result and drives signal, controlling the turn-on and turn-off of described switching tube,
The wherein said balancing circuitry that discharges and recharges comprises:
The switching sequence control circuit is used for producing the switching sequence control signal according to described ON time signal;
Charging and discharging currents balanced structure circuit, it is coupled to described switching sequence control circuit; And
Capacitor, its first end is coupled to described charging and discharging currents balanced structure circuit and its second end coupling grounding, described charging and discharging currents balanced structure circuit discharges and recharges described capacitor under the control of described switching sequence control signal, the described balancing circuitry that discharges and recharges provides the described signal that discharges and recharges at the first end of described capacitor
Wherein said charging and discharging currents balanced structure circuit comprises current balance module, described current balance module has electric current to be regulated the stage and discharges and recharges the stage, described current balance module carries out electric current in the described electric current adjusting stage and regulates to produce the first equal electric current and the second electric current, and discharges and recharges the stage and use described the first electric current that described capacitor is charged and use described the second electric current to described discharging capacitors described.
2. controller as claimed in claim 1, it is characterized in that, described current balance module is mirror current source, described mirror current source comprises the first transistor and transistor seconds, the grid of described the first transistor is coupled to the grid of described transistor seconds, described the first electric current described the first transistor and described the second electric current described transistor seconds of flowing through of flowing through, described current balance module is regulated the grid voltage of described the first transistor and described transistor seconds with described the first electric current and described the second difference between currents in the described electric current adjusting stage, thereby regulate the conducting resistance of described the first transistor and described transistor seconds, described first electric current of the described the first transistor of flowing through is equated with described second electric current of the described transistor seconds of flowing through.
3. controller as claimed in claim 1 or 2, it is characterized in that, described charging and discharging currents balanced structure circuit comprises a current balance module and comprises fixedly mirror current source, uses described fixedly mirror current source that described capacitor is discharged and recharged when described current balance module is in when described electric current is regulated the stage.
4. controller as claimed in claim 1 or 2, it is characterized in that, described charging and discharging currents balanced structure circuit comprises at least two current balance modules, in each cycle of described ON time signal, described switching sequence control signal make a current balance module in described at least two current balance modules enter described discharge and recharge the stage and make other current balance module enter described electric current regulate the stage, thereby described at least two current balance module alternatelies discharge and recharge described capacitor.
5. controller as claimed in claim 1 or 2 is characterized in that, described switching sequence control circuit comprises frequency divider and gate circuit, is used for producing described switching sequence control signal according to described ON time signal.
6. controller as claimed in claim 2 is characterized in that, described mirror current source also comprises inverter, is used for the extremely grid of described the first transistor and described transistor seconds of the voltage coupling that will be produced by described the first electric current and described the second difference between currents.
7. controller as claimed in claim 1, it is characterized in that, discharge and recharge the stage described, when the described fly-wheel diode of described ON time signal designation is cut-off, described current balance module uses described the first electric current that described capacitor is charged, and when the described fly-wheel diode of described ON time signal designation was conducting, described current balance module used described the second electric current to described discharging capacitors.
8. controller as claimed in claim 1 is characterized in that, described logic control circuit comprises:
The first rest-set flip-flop, its set termination is received described ON time signal, and its reset terminal receives described the first comparative result;
Inverter, its input is coupled to the output of described the first rest-set flip-flop;
The second rest-set flip-flop, its set end is coupled to the output of described inverter, and its reset terminal receives described the second comparative result; And
Driver, its input is coupled to the output of described the second rest-set flip-flop, and its output produces described driving signal.
9. Switching Power Supply comprises that described Switching Power Supply also comprises such as each described controller in the claim 1 to 8:
Transformer, the Same Name of Ends of its former limit winding receives input signal, and the different name end of its auxiliary winding is coupled to the input of described zero cross detection circuit, the Same Name of Ends coupling grounding of described auxiliary winding;
Switching tube, its drain coupled are to the different name end of the described former limit winding of described transformer, and its grid receives the described driving signal that described controller produces, and its source electrode is via described sampling resistor coupling grounding; And
Fly-wheel diode, its positive pole is coupled to the different name end of the secondary winding of described transformer, its negative pole is coupled to Same Name of Ends and the ground connection of described secondary winding via output capacitor, and wherein said Switching Power Supply provides output current to the load in parallel with described output capacitor.
10. method that is used for the control switch power supply, described Switching Power Supply comprises fly-wheel diode, switching tube and is coupled to the sampling resistor of described switching tube that described method comprises:
Detect the ON time of described fly-wheel diode to produce the ON time signal;
Under the control of described ON time signal, produce and discharge and recharge signal;
Discharge and recharge signal and the first reference voltage makes comparisons to produce the first comparative result with described;
To make comparisons to produce the second comparative result via sampled voltage signal and the second reference voltage that described sampling resistor produces; And
Produce according to described ON time signal, described the first comparative result and described the second comparative result and to drive signal, controlling the turn-on and turn-off of described switching tube,
Wherein produce and discharge and recharge signal and comprise:
Produce the switching sequence control signal according to described ON time signal; And
With described switching sequence control signal control charging and discharging currents balanced structure circuit capacitor is discharged and recharged, the first end of described capacitor is coupled to described charging and discharging currents balanced structure circuit and its second end coupling grounding, wherein the first end at described capacitor provides the described signal that discharges and recharges
Wherein said charging and discharging currents balanced structure circuit comprises current balance module, described switching sequence control signal is controlled described current balance module and is entered electric current adjusting stage or the stage of discharging and recharging, described current balance module carries out electric current in the described electric current adjusting stage and regulates to produce the first equal electric current and the second electric current, and discharges and recharges the stage and use described the first electric current that described capacitor is charged and use described the second electric current to described discharging capacitors described.
11. method as claimed in claim 10, it is characterized in that, described current balance module is mirror current source, described mirror current source comprises the first transistor and transistor seconds, the grid of described the first transistor is coupled to the grid of described transistor seconds, described the first electric current described the first transistor and described the second electric current described transistor seconds of flowing through of flowing through, wherein carry out electric current and regulate and comprise:
Regulate the grid voltage of described the first transistor and described transistor seconds with described the first electric current and described the second difference between currents, thereby regulate the conducting resistance of described the first transistor and described transistor seconds, described first electric current of the described the first transistor of flowing through is equated with described second electric current of the described transistor seconds of flowing through.
12. such as claim 10 or 11 described methods, it is characterized in that, also comprise:
When being in, described current balance module uses fixedly when described electric current is regulated the stage that mirror current source discharges and recharges described capacitor.
13., it is characterized in that described charging and discharging currents balanced structure circuit comprises at least two current balance modules such as claim 10 or 11 described methods, described method also comprises:
In each cycle of described ON time signal, described switching sequence control signal make a current balance module in described at least two current balance modules enter described discharge and recharge the stage and make other current balance module enter described electric current regulate the stage, thereby described at least two current balance module alternatelies discharge and recharge described capacitor.
14. method as claimed in claim 11 is characterized in that, the grid voltage of regulating described the first transistor and described transistor seconds comprises:
The voltage coupling that will be produced by described the first electric current and described the second difference between currents is to the grid of described the first transistor and described transistor seconds.
15. method as claimed in claim 10 is characterized in that, also comprises:
Discharge and recharge the stage described, when the described fly-wheel diode of described ON time signal designation is cut-off, described current balance module uses described the first electric current that described capacitor is charged, and when the described fly-wheel diode of described ON time signal designation was conducting, described current balance module used described the second electric current to described discharging capacitors.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105228287A (en) * | 2014-05-27 | 2016-01-06 | 昆山启达微电子有限公司 | For line voltage compensation circuit and the LED illumination circuit of LED illumination |
| CN105246207A (en) * | 2015-10-30 | 2016-01-13 | 上海晶丰明源半导体有限公司 | Starting circuit of chip, LED driver, LED drive circuit, and starting method of chip |
| CN105610337A (en) * | 2016-03-01 | 2016-05-25 | 北京京仪椿树整流器有限责任公司 | Method for controlling output voltage balancing of L-Boost multi-level circuit through peak current |
| CN106992699A (en) * | 2016-01-21 | 2017-07-28 | 华润矽威科技（上海）有限公司 | A kind of primary side feedback constant-current and constant-voltage control circuit and method |
| CN113131749A (en) * | 2021-03-16 | 2021-07-16 | 广州金升阳科技有限公司 | Flyback converter and control method |
| CN115800767A (en) * | 2023-01-31 | 2023-03-14 | 深圳市芯茂微电子有限公司 | Control method of switching power supply and switching power supply |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10215566A (en) * | 1997-01-30 | 1998-08-11 | Toshiba Corp | Power supply device |
| US6744649B1 (en) * | 2002-12-27 | 2004-06-01 | System General Corp. | Zero switching power converter operable as asymmetrical full-bridge converter |
| CN102364991A (en) * | 2011-02-01 | 2012-02-29 | 杭州士兰微电子股份有限公司 | Switching power supply controller for constant current driving of LED by primary side control and method for constant current driving of LED |
| CN203014693U (en) * | 2012-12-28 | 2013-06-19 | 杭州士兰微电子股份有限公司 | Controller for controlling switch power supply to output current constantly |
-
2012
- 2012-12-28 CN CN201210586813.4A patent/CN102983759B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10215566A (en) * | 1997-01-30 | 1998-08-11 | Toshiba Corp | Power supply device |
| US6744649B1 (en) * | 2002-12-27 | 2004-06-01 | System General Corp. | Zero switching power converter operable as asymmetrical full-bridge converter |
| CN102364991A (en) * | 2011-02-01 | 2012-02-29 | 杭州士兰微电子股份有限公司 | Switching power supply controller for constant current driving of LED by primary side control and method for constant current driving of LED |
| CN203014693U (en) * | 2012-12-28 | 2013-06-19 | 杭州士兰微电子股份有限公司 | Controller for controlling switch power supply to output current constantly |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105228287A (en) * | 2014-05-27 | 2016-01-06 | 昆山启达微电子有限公司 | For line voltage compensation circuit and the LED illumination circuit of LED illumination |
| CN105228287B (en) * | 2014-05-27 | 2018-02-23 | 昆山启达微电子有限公司 | Line voltage compensation circuit and LED illumination circuit for LED illumination |
| CN105246207A (en) * | 2015-10-30 | 2016-01-13 | 上海晶丰明源半导体有限公司 | Starting circuit of chip, LED driver, LED drive circuit, and starting method of chip |
| CN105246207B (en) * | 2015-10-30 | 2018-03-20 | 上海晶丰明源半导体股份有限公司 | The start-up circuit of chip, LED driver, the startup method of LED drive circuit and chip |
| CN106992699A (en) * | 2016-01-21 | 2017-07-28 | 华润矽威科技（上海）有限公司 | A kind of primary side feedback constant-current and constant-voltage control circuit and method |
| CN105610337A (en) * | 2016-03-01 | 2016-05-25 | 北京京仪椿树整流器有限责任公司 | Method for controlling output voltage balancing of L-Boost multi-level circuit through peak current |
| CN105610337B (en) * | 2016-03-01 | 2019-04-30 | 北京京仪椿树整流器有限责任公司 | A method of it is pressed by the output of peak value comparison method L-Boost multi-level circuit |
| CN113131749A (en) * | 2021-03-16 | 2021-07-16 | 广州金升阳科技有限公司 | Flyback converter and control method |
| CN115800767A (en) * | 2023-01-31 | 2023-03-14 | 深圳市芯茂微电子有限公司 | Control method of switching power supply and switching power supply |
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|---|---|
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