CN101605416B - LED driving circuit and controller thereof - Google Patents
LED driving circuit and controller thereof Download PDFInfo
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- CN101605416B CN101605416B CN 200810111282 CN200810111282A CN101605416B CN 101605416 B CN101605416 B CN 101605416B CN 200810111282 CN200810111282 CN 200810111282 CN 200810111282 A CN200810111282 A CN 200810111282A CN 101605416 B CN101605416 B CN 101605416B
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Abstract
The invention discloses an LED driving circuit and a controller thereof. The traditional balanced current LED driving circuit does not have a dimming function, a protection function, and the like. The LED driving circuit judges whether the driving of an LED is abnormal or not to determine if a protection mechanism is started according to potential detection signals of the controlled end, the first output/input end and the second output/input end of a semiconductor switch; and the LED driving circuit can also be controlled by dimming signals in any modes to regulate the brightness of the LED.
Description
Technical field
The present invention relates to a kind ofly for LED driving circuit and controller thereof, particularly relate to LED driving circuit and the controller thereof of a kind of tool light modulation and unusual feedback function.
Background technology
Light-emitting diode (Light Emitting Diode, LED) fluorescent tube that mainly throws light on compared to present conduct, there is the life-span long, power saving, low-voltage driving, safety, the advantages such as environmental protection, when especially being applied to the light source of panel of LCD (LCD panel) backlight module, its color saturation is far above cold cathode fluorescent lamp (the Cold Cathode Fluorescent Lamp of present main flow, CCFL), and have environmental protection (not mercurous) concurrently, conform with the standard that harmful substance limits the use of (Restriction of Hazardous Substances, ROHS) fully.Therefore, numerous manufacturers there's no one who doesn't or isn't endeavour to research and develop in the hope of replace other lighting source with light-emitting diode.
As shown in Figure 1, be the schematic circuit diagram of traditional current balance type (Current Balancing) LED driving circuit.One input power AC through one exchange turn direct current transducer 30 and change into first a direct current voltage VDD after, change into required driving voltage Vin through the direct current transducer 40 that circulates always again, to offer LED driving circuit.Wherein, this interchange turns direct current and changes 30 devices and comprise a bridge rectifier (not shown), convert this input power AC to a direct current voltage VDD, by the switching regulator change-over circuit (not shown) in the DC-DC transducer 40 this direct voltage VDD step-down is become driving voltage Vin again.This LED driving circuit has comprised a light-emitting diode (LED) module 10 and a current balancing device 20.Light-emitting diode (LED) module 10 by a plurality of light-emitting diodes parallel connection and being in series, and for the brightness convergence that makes every a string light-emitting diode consistent, need by current balancing device 20, the current balance type that every a string light-emitting diode is flow through unanimously reaches and is close to identical brightness.Current balancing device 20 reaches the current balance type effect with the framework of current mirror, and controls the size of current (electric current I=(VDD-VG)/R, VG is the grid voltage of semiconductor switch) of each light-emitting diode of flowing through by the adjustment of resistance R.
Traditional current balance type LED driving circuit there is no protection mechanism; if circuit has unusually; such as: but short circuit, open circuit, surpass opereating specification etc., and the current balance type LED driving circuit still can continue to operate and cause unnecessary power loss or circuit to damage.And traditional current balance type LED driving circuit also can't provide dimming function, can't cooperate demand to some application scenario (for example: backlight module), so also to some extent restriction on using.
Summary of the invention
In view of this, the invention provides the LED driving circuit of the functions such as a kind of tool light modulation and unusual feedback signal, according to the detection signal of light-emitting diode, judge whether the driving of light-emitting diode has unusually, come starting protection mechanism and decommission or indicating device; And can accept the control of the dim signal of any pattern, adjust the brightness of light-emitting diode.
To achieve these goals, the invention provides a kind of LED driving circuit, comprise a change-over circuit, at least one current control unit, at least one current detecting unit and a driving control unit.Above-mentioned change-over circuit couples an input power to convert a direct current output signal to drive a light-emitting diode (LED) module.Each this current control unit has a controlled pin position, one first import and export pin position and one second import and export pin position, and this first import and export pin position couples this light-emitting diode (LED) module.Each this current detecting unit correspondence couples this second import and export pin position of each this current control unit, to produce at least one detection signal.Above-mentioned driving control unit couples this controlled pin position, this first import and export pin position and this current detecting unit of this current control unit, this driving control unit is adjusted the level of the controlled pin position of this corresponding current control unit based on this detection signal, makes the current stabilization of this light-emitting diode (LED) module of flowing through near a predetermined current value.Wherein, when above-mentioned driving control unit is higher than first predetermined level in arbitrary this first import and export pin position, make this corresponding current control unit cut-off.
To achieve these goals, the present invention also provides another kind of LED driving circuit, comprises a change-over circuit, at least one current control unit, at least one current detecting unit and a driving control unit.Above-mentioned change-over circuit couples an input power to convert a direct current output signal to drive a light-emitting diode (LED) module.Each this current control unit has a controlled pin position, one first import and export pin position and one second import and export pin position, and this first import and export pin position couples this light-emitting diode (LED) module.Each this current detecting unit correspondence couples this second import and export pin position of each this current control unit, to produce at least one detection signal.Above-mentioned driving control unit couples this controlled pin position, this first import and export pin position and this current detecting unit of this current control unit, this driving control unit is adjusted the level of the controlled pin position of this corresponding current control unit based on this detection signal, makes the current stabilization of this light-emitting diode (LED) module of flowing through near a predetermined current value.Wherein, when above-mentioned driving control unit is higher than first predetermined level in arbitrary this first import and export pin position, send a rub-out signal.
Described LED driving circuit, wherein, this current control unit corresponding to described rub-out signal cut-off.
Described LED driving circuit, wherein, described change-over circuit comprises:
One transformer has a primary side and a primary side, and this primary side couples this input power, and this primary side produces this direct-flow output signal through a rectification unit;
One switches switches set, couples this primary side of this transformer, in order to according to control signal switched conductive and a cut-off state;
One output capacitance couples this primary side of this transformer, with the noise of this direct-flow output signal of filtering;
One voltage detection unit couples this primary side of this transformer, produces a voltage detection signal according to this direct-flow output signal; And
One primary side control unit produces this control signal according to this voltage detection signal, and this direct-flow output signal is stable near the predeterminated voltage value.
Described LED driving circuit, wherein, described change-over circuit comprises:
One inductance couples this input power;
One switches switch, couples this inductance, in order to according to control signal switched conductive and a cut-off state;
One rectification unit, an end couple coupling a little of this inductance and this diverter switch, and the other end couples this light-emitting diode (LED) module;
One output capacitance couples coupling a little of this rectification unit and this light-emitting diode (LED) module, so that this direct-flow output signal to be provided;
One voltage detection unit couples one of these light-emitting diode (LED) module two ends, and produces a voltage detection signal according to the level that couples this end; And
One TCU transfer control unit produces this control signal according to this voltage detection signal, makes this end level equalization that this voltage detection unit detects near a predeterminated voltage value.
Described LED driving circuit, wherein, each this current control unit comprises:
One current lens unit, comprise a plurality of semiconductor switchs, each semiconductor switch has a controlled end, one first import and export end and one second import and export end, these controlled ends are coupled to each other with as this controlled pin position, and these the first import and export ends couple this light-emitting diode (LED) module and these the second import and export ends all are coupled to this corresponding current detecting unit; And
One selected cell couples these the first import and export ends of these semiconductor switchs, selects a level signal of these the first import and export ends to export this driving control unit to.
Described LED driving circuit, wherein, described driving control unit receives a conducting pick-off signal, and according to this this at least one current control unit of conducting pick-off signal cut-off.
Described LED driving circuit, wherein, the time of described driving control unit beyond this at least one current control unit of cut-off, detect this at least one controlled pin position, when this at least one controlled pin position arbitrary is lower than second predetermined level, send this rub-out signal.
Described LED driving circuit, wherein, described driving control unit detects this at least one second import and export pin position, continues to be lower than one the 3rd predetermined level above after the scheduled time length time in this at least one the second import and export pin position arbitrary, sends this rub-out signal.
Described LED driving circuit, wherein, described driving control unit also receives a direct current dim signal, and exports accordingly a pulse-width signal.
To achieve these goals, the present invention also provides a kind of LED driving circuit controller, drive light-emitting diode (LED) module to control a LED driving circuit, this LED driving circuit controller comprises electric current regulation and control unit and a signal processing unit.Above-mentioned electric current regulation and control unit produces an electric current adjustment signal according to a current detection signal in order to the size of current of indicating a light-emitting diode (LED) module, to control a power switch that is series at this light-emitting diode (LED) module, make this current detection signal level equalization near a predeterminated voltage value.Above-mentioned signal processing unit detects one of this power switch and this light-emitting diode (LED) module and couples an electric potential signal, and receive this current detection signal, when this current detection signal is lower than one first predetermined level and continues a Preset Time length maybe this couples an electric potential signal and is higher than second predetermined level, export a rub-out signal.
Described LED driving circuit controller, wherein, described signal processing unit also receives a conducting pick-off signal, when this conducting pick-off signal is positioned at the level of representative cut-off, controls this first electric current adjustment signal and makes this first power switch cut-off.
Described LED driving circuit controller, wherein, described signal processing unit receives a direct current dim signal, and exports accordingly a pulse-width signal.
Described LED driving circuit controller, wherein, described signal processing unit is controlled this first electric current adjustment signal according to this pulse-width signal and this first power switch is periodically ended reach dimming function.
Described LED driving circuit controller, wherein, also comprise one second electric current regulation and control unit, one second current detection signal according to the size of current of indicating one second light-emitting diode (LED) module produces one second electric current adjustment signal to control one second power switch of this second light-emitting diode (LED) module of series connection, makes this second current detection signal level equalization near one second predeterminated voltage value.
Described LED driving circuit controller, wherein, described signal processing unit also detects one second of this second power switch and this second light-emitting diode (LED) module and couples an electric potential signal and receive this second current detection signal, when this second current detection signal is lower than this first predetermined level and continues this Preset Time length or this second and couple an electric potential signal and be higher than this second predetermined level, export this rub-out signal.
Described LED driving circuit controller, wherein, described the first predeterminated voltage value equals this second predeterminated voltage value.
Described LED driving circuit controller, wherein, described signal processing unit also receives a conducting pick-off signal, when this conducting pick-off signal is positioned at the level of representative cut-off, control this first electric current adjustment signal, the second electric current adjustment signal makes respectively this first power switch, this second power switch cut-off.
Described LED driving circuit controller, wherein, described signal processing unit is this first electric current adjustment signal of time detecting beyond this conducting pick-off signal is positioned at the level of representative cut-off and the level of this second electric current adjustment signal also, when this first electric current adjustment signal and the arbitrary level of this second electric current adjustment signal are lower than the 3rd predetermined level, export this rub-out signal.
Described LED driving circuit controller, wherein, described signal processing unit is controlled this first electric current adjustment signal and this second electric current adjustment signal according to this pulse-width signal and this first power switch and this second power switch is periodically ended reach dimming function.
Described LED driving circuit controller, wherein, it is poor to have a Preset Time between the cut-off of described the first power switch and this second power switch.
Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.
Description of drawings
Fig. 1 is the schematic circuit diagram of traditional current balance type LED driving circuit;
Fig. 2 is the circuit diagram of LED driving circuit according to a preferred embodiment of the present invention;
Fig. 3 is the circuit diagram according to the driving control unit of one embodiment of the invention;
Fig. 4 is the circuit diagram of driving control unit according to another embodiment of the present invention;
Fig. 5 is according to the again circuit diagram of the driving control unit of an embodiment of the present invention; And
Fig. 6 is the circuit diagram of LED driving circuit according to still another embodiment of the invention.
The Reference numeral of prior art:
Light-emitting diode (LED) module 10
Current balancing device 20
Interchange turns direct current transducer 30
DC-DC transducer 40
Input power AC
Resistance R
Direct voltage VDD
Driving voltage Vin
Reference numeral among the present invention:
Light-emitting diode (LED) module 110,110a, 110b, 110c
Current detecting unit 122,122a, 122b, 122c
Driving control unit 130
Electric current regulation and control unit 134,134a, 134b, 134c
Divide facies unit 136
Or door 138
Change-over circuit 200,200 '
Converting unit 210 '
Auxiliary rectifier unit 214 '
Auxiliary output capacitance 216 '
Primary side control unit 220
TCU transfer control unit 220 '
Voltage detection unit 230,230 '
Comparator 302,304,306,308
With door 310
Or door 312
Time filtering unit 314,316,318
Input power AC
Bridge rectifier BD
Frequency signal Clock
Inhibit signal Delay
Rub-out signal FAULT, FAULTa, FAULTb, FAULTc
Conducting pick-off signal ONOFF
Direct current dim signal PWMDC
Pulse-width signal PWM, PWMa, PWMb, PWMc
Resistance R
Driving voltage VDD
Direct-current input power supplying Vdc
Direct-flow output signal Vout
The first predetermined level Vref1
The second predetermined level Vref2
The 3rd predetermined level Vref3
The 4th predetermined level Vref4
Current detection signal S1
Couple an electric potential signal S2
Controlled pin position electric potential signal S3
Diverter switch group SW
Transformer T
Embodiment
Below in conjunction with the drawings and specific embodiments technical scheme of the present invention is made further more detailed description.
LED driving circuit with fixed voltage driving light-emitting diode does not have light modulation and protection mechanism at present.LED driving circuit of the present invention also can be carried out light modulation according to a dim signal except the circuit abnormality protection mechanism can be provided, and reaches the function of the synchronous light modulation of multi-group light-emitting diode drive circuit by output light modulation pulse-width signal.Below will technology of the present invention be described with a plurality of embodiment.
Please refer to Fig. 2, be the circuit diagram of according to a preferred embodiment of the present invention LED driving circuit.This LED driving circuit comprises a change-over circuit 200, a current control unit 120, a current detecting unit 122, a driving control unit 130.This change-over circuit 200 couples an input power AC to convert a direct current output signal Vout to drive a light-emitting diode (LED) module 110.This current control unit 120 comprises the semiconductor switch, and has a controlled pin position, one first import and export pin position and one second import and export pin position.The first import and export pin position of this current control unit 120 couples this light-emitting diode (LED) module 110 and forms series connection.This current detecting unit 122 can be a resistance, couples this second import and export pin position of this current control unit 120, produces a current detection signal S1 with the size of current according to this light-emitting diode (LED) module 110 of flowing through.This driving control unit 130 couples this controlled pin position, this first import and export pin position and this current detecting unit 122 of this current control unit 120, and adjust the level of this controlled pin position of this current control unit 120 based on this detection signal S1, to adjust the equivalent resistance size of this current control unit 120, make the current stabilization of this light-emitting diode (LED) module 110 of flowing through near a predetermined current value.
Above-mentioned change-over circuit 200 can be flyback power-switching circuit, forward type power-switching circuit, push-pull type power-switching circuit, semibridge system power-switching circuit, full-bridge type power-switching circuit or DC-to-DC switching circuit, at this embodiment the present invention is described as an example of the flyback power-switching circuit example.This flyback power-switching circuit comprises a transformer T, and switches switches set SW(at feedback reverting circuit, the diverter switch group comprises the semiconductor switch, and at other type conversion circuit, as: semibridge system, full-bridge type may comprise several semiconductor switchs), an output capacitance 216, a voltage detection unit 230 and a primary side control unit 220.This transformer T has a primary side and a primary side, and this primary side couples this input power AC by a bridge rectifier BD, and this primary side produces this direct-flow output signal Vout through a rectification unit 214.This diverter switch group SW couples this primary side of this transformer T, to switch to conducting and cut-off state according to a control signal.This output capacitance 216 couples this primary side of this transformer T, with the noise of this direct-flow output signal of filtering Vout, makes the voltage stabilization of direct-flow output signal Vout.Voltage detection unit 230 couples this primary side of this transformer T, and the level height that detects this direct-flow output signal Vout to be producing a voltage detection signal, and is sent to this primary side control unit 220 by an isolated location 232 again.By isolated location 232, can effectively isolate primary side and the primary side of this transformer T.This primary side control unit 220 confirms according to this voltage detection signal of feedback whether this direct-flow output signal Vout is too high or too low, to adjust the pulsewidth of this control signal that is produced, this direct-flow output signal Vout is stable near the predeterminated voltage value.
The primary side of above-mentioned transformer T can comprise an input capacitance 212, initial drive circuit 222 and a primary side ancillary coil.Input capacitance 212 is in order to stablize the level through the direct current input voltage of bridge rectifier BD.This initial drive circuit 222 comprises a resistance, an electric capacity and a diode.After this input power AC connects this bridge rectifier BD, begin this capacitor charging by this resistance.When the voltage of this electric capacity reached a triggering level, this primary side control unit 220 came into operation, and controlled the switching of this diverter switch group SW.The primary side ancillary coil will be stored in the energy of transformer T by this capacitor charging of diode pair of initial drive circuit 222, and compare for fixing because of the coil of this primary side ancillary coil with this primary side, when this direct-flow output signal Vout is stable near the predeterminated voltage value, this capacitance voltage of this initial drive circuit 222 also will be stable near the magnitude of voltage.In addition, the primary side of transformer T also can comprise a primary side ancillary coil.In like manner, have under the fixing coil ratio in this primary side ancillary coil and this secondary side coil, the voltage that charges to an auxiliary output capacitance 216 ' through an auxiliary rectifier unit 214 ' also is stable at a magnitude of voltage, drives this driving control unit 130 so that a driving voltage VDD to be provided.
Driving control unit 130 comprises a signal processing unit 132 and electric current regulation and control unit 134.The electric current of light-emitting diode (LED) module 110 of the flowing through current detecting unit 122 of can flowing through simultaneously, current detecting unit 122 thereby produce this in order to the current detection signal S1 of the size of current that indicates light-emitting diode (LED) module 110.Electric current regulation and control unit 134 can be a comparator, adjust the electric current adjustment signal of its output by comparing current detection signal S1 and one first predetermined level Vref1, with the current potential of the controlled pin position of regulating and control semiconductor switch in this current control unit 120, namely grid potential.So, the equivalent resistance of this semiconductor switch of capable of regulating, and make this current detection signal S1 level equalization near this first predetermined level Vref1, the electric current of the light-emitting diode (LED) module 110 of namely flowing through can be stable at a predetermined current value.The controlled pin position electric potential signal S3 and one that this signal processing unit 132 receives this current detection signal S1, this current control unit 120 couples an electric potential signal S2 (electric potential signal of the second import and export pin position of current control unit 120), one second predetermined level Vref2, one the 3rd predetermined level Vref3, one the 4th predetermined level Vref4, a conducting pick-off signal ONOFF, a direct current dim signal PWMDC and a frequency signal Clock.This signal processing unit 132 judges based on these above-mentioned signals whether LED driving circuit is unusual, if have and unusually then send a rub-out signal FAULT, this rub-out signal is sent to primary side control unit 220 as can be as shown in Figure 2, is determined whether to stop the running of LED driving circuit by primary side control unit 220.Perhaps, also may be output to the microprocessor of system, for example: the image microprocessor of liquid crystal screen display determines processing mode by microprocessor; Or via a User's Interface assembly, for example: the mistake indicator light, notify the user, there is the user to determine whether to stop the running of LED driving circuit.The detailed running of driving control unit 130 and internal circuit are with following explanation.
Please refer to Fig. 3, be the circuit diagram according to the driving control unit of one embodiment of the invention.Driving control unit 130 comprises a signal processing unit 132 and electric current regulation and control unit 134.Signal processing unit 132 comprises comparator 302,304,306 and 308, one and door 310, one or door 312, time filtering unit 314,316 and 318, an and ramp signal generator 320.Electric current regulation and control unit 134 can be comparator, relatively current detection signal S1 and the first predetermined level Vref1.When current detection signal S1 is lower than this first predetermined level Vref1, heighten the level of the electric current adjustment signal of exporting, it is the grid potential of the semiconductor switch in the current control unit 120, the equiva lent impedance of semiconductor switch is descended, improve the size of current of light-emitting diode (LED) module 110 and the level of current detection signal S1; When current detection signal S1 is higher than this first predetermined level Vref1, turn down the level of the electric current adjustment signal of exporting, the equiva lent impedance of semiconductor switch is risen, reduce the size of current of light-emitting diode (LED) module 110 and the level of current detection signal S1.By above-mentioned feedback control mechanism, make the current stabilization of light-emitting diode (LED) module 110 near the predetermined current value.
Comparator 302 in the signal processing unit 132 relatively the 3rd predetermined level Vref3 and this current control unit 120 and this light-emitting diode (LED) module 110 couple an electric potential signal S2, the i.e. electric potential signal of the second import and export pin position of this current control unit 120.Under normal condition, this couples an electric potential signal S2 and can drop in the ESD protection area (SOA, safe operating area), and in other words, this couples an electric potential signal S2 can be lower than the 3rd predetermined level Vref3.The setting of the 3rd predetermined level Vref3 considers to be that this couples an electric potential signal S2 and whether surpasses voltage that this current control unit 120 can bear or too high and cause conversion efficiency not high, and it can be produced or provided by the outside by driving control unit 130 is inner.For example: this current control unit 120 is by 30 volts of withstand voltage manufacture method mades, the 3rd predetermined level Vref3 can be set in 25 volts, perhaps direct-flow output signal Vout is 30 volts, and under conversion efficiency was consideration more than 80%, the 3rd predetermined level Vref3 can be set in 6 volts.The situation that has light-emitting diode to damage short circuit or other short circuit in light-emitting diode (LED) module 110 occurs and causes the cross-pressure on the light-emitting diode (LED) module 110 to reduce, make this couple the potential rise of electric potential signal S2 and surpass the 3rd predetermined level Vref3, the unusual high level signal of these comparator 302 output representatives to or door 312.It is noted that what this coupled an electric potential signal S2 more also can set two or more comparative levels simultaneously, for example 6 volts in the above-mentioned example and 25 volts, and different suitable processing can be provided under different conditions.
Under normal condition, the semiconductor switch of this current control unit 120 can operate in linear zone, to reach the effect of the equiva lent impedance of adjusting this current control unit 120 by the current potential of adjusting controlled pin position.So, when conducting pick-off signal ONOFF is the low level signal of representative cut-off, the electric current adjustment signal will be in low level and make this current control unit 120 be cut-off, and detect this controlled pin position electric potential signal S3 this moment will misjudgment.So comparator 306 decommissions, and be positioned at the level of level this electric current adjustment signal of time detecting in addition of representative cut-off in this conducting pick-off signal when this conducting pick-off signal ONOFF is positioned at the level of representative cut-off.When this current control unit 120 is damaged and during short circuit, in any case controlled pin position electric potential signal S3 turns down the size of current that can't reduce light-emitting diode (LED) module 110, this moment, the controlled pin position electric potential signal S3 of this current control unit 120 can be lower than the 4th predetermined level Vref4, and comparator 306 will be exported the unusual high level signal of representative.For avoiding this conducting pick-off signal ONOFF to cause the possible erroneous judgement of comparator 306 at conversion process, but by the possible erroneous judgement of time filtering unit 318 filterings.
When or door 312 when receiving in the comparators 302,304 and 306 arbitrary abnormal signal that transmits, namely represent the unusual and output error signal FAULT of circuit operation.In addition, when circuit operation unusual and when sending rub-out signal FAULT, can be as shown in Figure 3 as, by closing the operation of driving control unit 130 with door 310, other microprocessor or user of reporting system only perhaps as above-mentioned.Certainly, in the practical application, can according to the reason of circuit abnormality process and be not limited to the present invention for the application mode of embodiment.
Dim signal also may be the direct current dim signal except being the pulse signal as above-mentioned.As shown in Figure 3, the ramp signal that comparator 308 reception direct current dim signal PWMDC and ramp signal generator 320 produce, and export accordingly a pulse-width signal PWMOUT.By this, the driving control unit of other group LED driving circuit reaches this pulse-width signal PWMOUT the function of synchronous light modulation as conducting pick-off signal ONOFF input.If without above-mentioned synchronisation requirement, this pulse-width signal PWMOUT can be failed back former driving control unit 130 as conducting pick-off signal ONOFF and periodically end this current control unit 120 and reach dimming function.On the practice output of this pulse-width signal PWMOUT of driving control unit 130 and the input of conducting pick-off signal ONOFF are packaged into respectively two different pins, when dim signal is direct current light modulation and during without synchronisation requirement, above-mentioned two pins are connected get final product.
Please refer to Fig. 4, be the circuit diagram of according to another embodiment of the present invention driving control unit.The embodiment of Fig. 4 and the embodiment of Fig. 3 compare, and main difference is in current control unit 120.Current control unit 120 shown in Figure 4 comprises a current lens unit 124 and a selected cell 126.This current lens unit 124 comprises a plurality of semiconductor switchs, each semiconductor switch has a controlled end, one first import and export end and one second import and export end, these controlled ends are coupled to each other with the controlled pin position as this current control unit 120, and these the first import and export ends couple this light-emitting diode (LED) module 110 and these the second import and export ends all are coupled to this corresponding current detecting unit 122 with the second import and export pin position as this current control unit 120.This selected cell 126 couples the first import and export end of these semiconductor switchs of this current lens unit 124, selects these the first import and export ends of output level signal wherein to export this driving control unit 130 to as coupling an electric potential signal S2.This selected cell 126 can comprise a plurality of diodes, the anode of these diodes is corresponding first import and export ends that are coupled to the semiconductor switch in this current lens unit 124 respectively, and the negative terminal of these diodes then is coupled to each other as the first import and export pin position of this current control unit 120.So, this selected cell 126 can have maximum potential person in the first import and export end of these semiconductor switchs of output, when namely causing the undesired rising of the first import and export end of a certain semiconductor switch when unusual generation is arranged, driving control unit 130 can be declared and know and output error signal FAULT.By this, driving control unit of the present invention can be driven and have more the application many and light-emitting diode (LED) modules of going here and there more.
Please refer to Fig. 5, be the again circuit diagram of the driving control unit of an embodiment according to the present invention.Compared to embodiment shown in Figure 4, the driving control unit 130 of Fig. 5 is judged and the execute exception protection mechanism individually with the signal processing unit 132 that a plurality of signal processor 132a, 132b, 132c are consisted of.In Fig. 5, the assembly that has an identical function with the assembly of embodiment shown in Figure 3 will give the same components numbering and add a, b according to corresponding control group, c is distinguished.Because the operation of the inter-module of each control group only illustrates the signal relation of respectively controlling between group as the explanation of Fig. 3 at this.In the present embodiment, switch when avoiding semiconductor switch 120a, 120b, 120c and cause larger mains ripple (volatge ripple), by one minute facies unit 136, it produces pulse-width signal PWMa, PWMb, PWMc according to inhibit signal Delay and controls respectively electric current regulation and control unit 134a, 134b, 134c, makes conducting and the cut-off of these semiconductor switchs 120a, 120b, 120c have the time difference.This inhibit signal Delay can be by external signal or by driving control unit 130 inner generations.When judging corresponding LED driving circuit, any signal processor 132a, 132b, 132c have unusually, for example: the controlled pin position of semiconductor switch 120a, 120b, 120c is arbitrary Vref4 when being lower than the 4th predetermined level; The arbitrary of the second import and export pin position continues to be lower than one second predetermined level Vref2 above a scheduled time length; Appointing of the first import and export pin position is higher than one the 3rd predetermined level Vref3, driving control unit 130 can be selected only to end semiconductor switch 120a, 120b in this corresponding current control unit or 120c and close the running of unusual LED driving circuit, or end semiconductor switch 120a, 120b and 120c in this whole current control units, and then by or door 138 send rub-out signal FAULT.The pulse light modulation signal that minute facies unit 136 receives is except can being the above-mentioned conducting pick-off signal ONOFF, can also be a direct current dim signal PWMDC, and by arbitrary signal processor 132a, 132b, 132c, the pulse light modulation signal that signal processor 132c as shown in Figure 5 converts to.Divide facies unit 136 and will export a pulse-width signal PWMOUT as the synchronous usefulness of other circuit.In addition, light-emitting diode (LED) module 110a, 110b, 110c can be identical light-emitting diode or different light-emitting diodes, for example are respectively red light emitting diodes module, green LED module, blue LED module.When being identical light-emitting diode (LED) module, the first predetermined level Vref1 that each electric current regulation and control unit 134a, 134b, 134c receive can be for identical; And when being different light-emitting diode (LED) module, these first predetermined level Vref1 can be difference.
Please refer to Fig. 6, be the circuit diagram of according to still another embodiment of the invention LED driving circuit.Compared to the above embodiments, change-over circuit 200 ' in the LED driving circuit of Fig. 6 is the DC-DC voltage up converting circuit, its ratio of boosting (output voltage/input voltage) is determined by the duty ratio of the control signal of PDM keyer, but not is determined to be compared by coil as transformer.Change-over circuit 200 ' shown in Figure 6 comprises a converting unit 210 ', a TCU transfer control unit 220 ' (being PDM keyer) and a voltage detection unit 230 '.This converting unit 210 ' comprises an inductance, a rectification unit, an electric capacity and a switching switch.This inductance couples a direct current input power Vdc, and this diverter switch couples this inductance, switches between conducting and cut-off state in order to the control signal that produces according to TCU transfer control unit 220 '.One end of this rectification unit couples coupling a little of this inductance and this diverter switch, and the other end couples a light-emitting diode (LED) module 110.This electric capacity couples coupling a little of this rectification unit and this light-emitting diode (LED) module 110, so that this direct-flow output signal Vout to be provided.This voltage detection unit 230 ' couples one of these light-emitting diode (LED) module 110 two ends, and produces a voltage detection signal according to the level that couples this end.TCU transfer control unit 220 ' produces this control signal according to this voltage detection signal, makes this end level equalization that this voltage detection unit 230 ' detects near a predeterminated voltage value.As shown in Figure 6, this voltage detection unit 230 ' couples the negative terminal of this light-emitting diode (LED) module 110, be the first import and export pin position of current control unit 120, the voltage stabilization that can make by this this first import and export pin position is on a predetermined magnitude of voltage and guarantee the conversion efficiency of LED driving circuit.
Certainly; the present invention also can have other various embodiments; in the situation that does not deviate from spirit of the present invention and essence thereof; those of ordinary skill in the art work as can make according to the present invention various corresponding changes and distortion, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the present invention.
Claims (20)
1. a LED driving circuit is characterized in that, comprises:
One change-over circuit couples an input power to convert a direct current output voltage to drive a light-emitting diode (LED) module;
At least one current control unit, each current control unit comprises the semiconductor switch, and this current control unit has a controlled pin position, one first import and export pin position and one second import and export pin position, and this first import and export pin position couples this light-emitting diode (LED) module;
At least one current detecting unit couples this second import and export pin position of at least one this current control unit, to produce at least one detection voltage according to the size of current of this light-emitting diode (LED) module of flowing through is corresponding; And
One driving control unit, couple this controlled pin position of this current control unit, this the first import and export pin position and this current detecting unit, this driving control unit is adjusted the level of this controlled pin position of this corresponding current control unit according at least one this detection voltage that receives, make the current stabilization of this light-emitting diode (LED) module of flowing through near a predetermined current value, and this driving control unit also receives a dim signal, and reaches dimming function according to this semiconductor switch running of at least one this current control unit of the corresponding control of this dim signal with the electric current that periodically ends this light-emitting diode (LED) module;
Wherein, when the voltage of this driving control unit in arbitrary this first import and export pin position is higher than first pre-set threshold value, send a rub-out signal.
2. LED driving circuit according to claim 1 is characterized in that, this current control unit corresponding to described rub-out signal cut-off.
3. LED driving circuit according to claim 1 and 2 is characterized in that, described change-over circuit comprises:
One transformer has a primary side and a primary side, and this primary side couples this input power, and this primary side produces this VD through a rectification unit;
One switches switches set, couples this primary side of this transformer, in order to according to control signal switched conductive and a cut-off state;
One output capacitance couples this primary side of this transformer, with the noise of this VD of filtering;
One voltage detection unit couples this primary side of this transformer, produces a voltage detection signal according to this VD; And
One primary side control unit produces this control signal according to this voltage detection signal, and this VD is stable near the predeterminated voltage value.
4. LED driving circuit according to claim 1 and 2 is characterized in that, described change-over circuit comprises:
One inductance couples this input power;
One switches switch, couples this inductance, in order to according to control signal switched conductive and a cut-off state;
One rectification unit, an end couple coupling a little of this inductance and this diverter switch, and the other end couples this light-emitting diode (LED) module;
One output capacitance couples coupling a little of this rectification unit and this light-emitting diode (LED) module, so that this direct-flow output signal to be provided;
One voltage detection unit couples one of these light-emitting diode (LED) module two ends, and produces a voltage detection signal according to the level that couples this end; And
One TCU transfer control unit produces this control signal according to this voltage detection signal, makes this end level equalization that this voltage detection unit detects near a predeterminated voltage value.
5. LED driving circuit according to claim 1 and 2 is characterized in that, described driving control unit receives a conducting cut-ff voltage, and according at least one this current control unit of this conducting cut-ff voltage cut-off.
6. LED driving circuit according to claim 5, it is characterized in that, the time of described driving control unit beyond at least one this current control unit of cut-off, detect at least one this controlled pin position, when at least one this controlled pin position arbitrary is lower than second pre-set threshold value, send this rub-out signal.
7. LED driving circuit according to claim 5, it is characterized in that, described driving control unit detects at least one this second import and export pin position, in the time of after at least one this second import and export pin position arbitrary continues to be lower than one the 3rd pre-set threshold value to surpass a scheduled time length, send this rub-out signal.
8. LED driving circuit according to claim 1 and 2 is characterized in that, described dim signal is a direct current dim signal, and described driving control unit is exported a pulse-width signal according to this direct current dim signal.
9. a LED driving circuit is characterized in that, comprises: a change-over circuit, at least one current control unit, at least one current detecting unit and a driving control unit; Each this current control unit comprises a current lens unit and a selected cell;
This change-over circuit couples an input power to convert a direct current output voltage to drive a light-emitting diode (LED) module;
This current lens unit, comprise a plurality of semiconductor switchs, each semiconductor switch has a controlled end, one first import and export end and one second import and export end, these controlled ends are coupled to each other with as controlled pin position, these the first import and export ends couple this light-emitting diode (LED) module, and these the second import and export ends all are coupled to this corresponding current detecting unit;
This selected cell couples these the first import and export ends of these semiconductor switchs, selects a level signal of these the first import and export ends to export this driving control unit to;
This at least one current detecting unit couples these the second import and export ends of at least one this current control unit, to produce at least one detection voltage according to the size of current of this light-emitting diode (LED) module of flowing through is corresponding; And
This driving control unit, couple this controlled pin position of this current control unit, this the first import and export pin position and this current detecting unit, this driving control unit is adjusted the level of this controlled pin position of this corresponding current control unit according at least one this detection voltage that receives, make the current stabilization of this light-emitting diode (LED) module of flowing through near a predetermined current value, and this driving control unit also receives a dim signal, and reaches dimming function according to these semiconductor switch runnings of at least one this current control unit of the corresponding control of this dim signal with the electric current that periodically ends this light-emitting diode (LED) module; Wherein, when the voltage of this driving control unit in arbitrary this first import and export pin position is higher than first pre-set threshold value, send a rub-out signal.
10. controller that is used for LED driving circuit claimed in claim 1, it is characterized in that, the controller of this LED driving circuit is controlled this LED driving circuit and is driven this light-emitting diode (LED) module, and the controller of this LED driving circuit comprises:
One first electric current regulation and control unit, one first detect voltage and produce one first electric current adjustment signal to control one first semiconductor switch in this corresponding first current control unit according to what the size of current of this light-emitting diode (LED) module of flowing through produced according to one first corresponding at least one this current detecting unit current detecting unit, make this first detect voltage stabilization near one first predeterminated voltage value; And
One signal processing unit, detecting one first of this first semiconductor switch and this light-emitting diode (LED) module couples an electric potential signal and receives this first detection voltage, first when detecting voltage and being lower than one second pre-set threshold value and continuing a Preset Time length or this first and couple an electric potential signal and be higher than the 3rd pre-set threshold value, export this rub-out signal in this.
11. the controller of LED driving circuit according to claim 10, it is characterized in that, described signal processing unit also receives a conducting cut-ff voltage, when this conducting cut-ff voltage is the level of representative cut-off, controls this first electric current adjustment signal and makes this first semiconductor switch cut-off.
12. the controller of LED driving circuit according to claim 10 is characterized in that, described signal processing unit receives a direct current dim signal, and exports accordingly a pulse-width signal.
13. the controller of LED driving circuit according to claim 12, it is characterized in that described signal processing unit is controlled this first electric current adjustment signal according to this pulse-width signal and this first semiconductor switch periodically ended reach dimming function.
14. the controller of LED driving circuit according to claim 10, it is characterized in that, also comprise one second electric current regulation and control unit, one second detect voltage and produce one second electric current adjustment signal with one second semiconductor switch of this light-emitting diode (LED) module of control series connection according to what one second corresponding at least one this current detecting unit current detecting unit produced, make this second detect voltage stabilization near one second predeterminated voltage value.
15. the controller of LED driving circuit according to claim 14, it is characterized in that, described signal processing unit also detects one second of this second semiconductor switch and this light-emitting diode (LED) module and couples an electric potential signal and receive this second detection voltage, second when detecting voltage and being lower than this second pre-set threshold value and continuing this Preset Time length or this second and couple an electric potential signal and be higher than the 3rd pre-set threshold value, export this rub-out signal in this.
16. the controller of LED driving circuit according to claim 14 is characterized in that, described the first predeterminated voltage value equals this second predeterminated voltage value.
17. the controller of LED driving circuit according to claim 14, it is characterized in that, described signal processing unit also receives a conducting cut-ff voltage, when this conducting cut-ff voltage is the level of representative cut-off, control this first electric current adjustment signal, the second electric current adjustment signal makes respectively this first semiconductor switch, this second semiconductor switch cut-off.
18. the controller of LED driving circuit according to claim 14, it is characterized in that, described signal processing unit is this first electric current adjustment signal of time detecting beyond this conducting cut-ff voltage is the level of representative cut-off and the level of this second electric current adjustment signal also, when this first electric current adjustment signal and the arbitrary level of this second electric current adjustment signal are lower than the 4th pre-set threshold value, export this rub-out signal.
19. the controller of LED driving circuit according to claim 14, it is characterized in that described signal processing unit is controlled this first electric current adjustment signal and this second electric current adjustment signal according to a pulse-width signal and this first semiconductor switch and this second semiconductor switch periodically ended reach dimming function.
20. according to claim 17 or the controller of 19 described LED driving circuit, it is characterized in that it is poor to have a Preset Time between described the first semiconductor switch and the cut-off of this second semiconductor switch.
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| CN 200810111282 CN101605416B (en) | 2008-06-13 | 2008-06-13 | LED driving circuit and controller thereof |
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| CN 200810111282 CN101605416B (en) | 2008-06-13 | 2008-06-13 | LED driving circuit and controller thereof |
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Families Citing this family (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9030122B2 (en) | 2008-12-12 | 2015-05-12 | O2Micro, Inc. | Circuits and methods for driving LED light sources |
| US9232591B2 (en) | 2008-12-12 | 2016-01-05 | O2Micro Inc. | Circuits and methods for driving light sources |
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| US8330388B2 (en) * | 2008-12-12 | 2012-12-11 | O2Micro, Inc. | Circuits and methods for driving light sources |
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| CN102014540B (en) | 2010-03-04 | 2011-12-28 | 凹凸电子（武汉）有限公司 | Drive circuit and controller for controlling electric power of light source |
| US8508150B2 (en) | 2008-12-12 | 2013-08-13 | O2Micro, Inc. | Controllers, systems and methods for controlling dimming of light sources |
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| US8698419B2 (en) | 2010-03-04 | 2014-04-15 | O2Micro, Inc. | Circuits and methods for driving light sources |
| US8247992B2 (en) * | 2010-03-23 | 2012-08-21 | Green Mark Technology Inc. | LED driver circuit |
| CN102244952A (en) * | 2010-05-11 | 2011-11-16 | 登丰微电子股份有限公司 | Feedback control circuit and power conversion circuit |
| JP5595126B2 (en) * | 2010-06-03 | 2014-09-24 | ローム株式会社 | LED driving device and electronic apparatus equipped with the same |
| US8111017B2 (en) | 2010-07-12 | 2012-02-07 | O2Micro, Inc | Circuits and methods for controlling dimming of a light source |
| US10057952B2 (en) * | 2010-12-15 | 2018-08-21 | Cree, Inc. | Lighting apparatus using a non-linear current sensor and methods of operation thereof |
| TWI523568B (en) * | 2011-02-15 | 2016-02-21 | 力林科技股份有限公司 | Light emitting diode driving apparatus |
| CN102098855B (en) * | 2011-02-20 | 2013-10-23 | 苏州达方电子有限公司 | Light-emitting diode (LED) driving device |
| TW201238388A (en) | 2011-03-02 | 2012-09-16 | Green Solution Tech Co Ltd | LED driving circuit and short-circuit protection circuit |
| CN102685969B (en) * | 2011-03-15 | 2015-03-11 | 登丰微电子股份有限公司 | LED (Light-Emitting Diode) drive circuit and short-circuit protection circuit |
| CN102750913B (en) * | 2011-04-18 | 2015-04-29 | 青岛海信电器股份有限公司 | Driving circuit and liquid crystal television |
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| CN102957136B (en) * | 2011-08-19 | 2015-01-14 | 登丰微电子股份有限公司 | Load driving circuit with inrush current protection |
| CN103248031B (en) * | 2012-02-07 | 2015-10-07 | 登丰微电子股份有限公司 | There is the load driving circuits of impulse current protection |
| CN103298189B (en) * | 2012-03-01 | 2018-01-19 | 欧司朗股份有限公司 | Lighting device |
| CN102646402B (en) * | 2012-04-20 | 2014-04-16 | 青岛海信电器股份有限公司 | Backlight driving voltage control device, backlight driving voltage control method and television |
| CN102833916B (en) * | 2012-08-23 | 2014-10-15 | 冠捷显示科技（厦门）有限公司 | DC (direct current) dimming type LED (Light Emitting Diode) drive circuit |
| CN102982771B (en) * | 2012-11-28 | 2016-01-13 | 深圳市华星光电技术有限公司 | A kind of backlight drive circuit and liquid crystal display |
| CN105388199A (en) * | 2015-12-25 | 2016-03-09 | 张萍 | Electrode blood glucose meter with telecommunication function and high antijamming capability |
| CN112953229A (en) * | 2019-12-10 | 2021-06-11 | 产晶积体电路股份有限公司 | Dynamic multifunctional power supply controller |
| CN114141207B (en) * | 2021-12-14 | 2023-04-18 | 深圳市康冠科技股份有限公司 | Constant current backlight and balanced inductor |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1521720A (en) * | 2003-01-29 | 2004-08-18 | 胜园科技股份有限公司 | Digital drive method and apparatus for active organic light-emitting diode display |
| CN101056485A (en) * | 2006-04-11 | 2007-10-17 | 硕颉科技股份有限公司 | Driving circuit of backlight device with the protection module group |
| JP2008027688A (en) * | 2006-07-20 | 2008-02-07 | Sharp Corp | Surface light source device |
-
2008
- 2008-06-13 CN CN 200810111282 patent/CN101605416B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1521720A (en) * | 2003-01-29 | 2004-08-18 | 胜园科技股份有限公司 | Digital drive method and apparatus for active organic light-emitting diode display |
| CN101056485A (en) * | 2006-04-11 | 2007-10-17 | 硕颉科技股份有限公司 | Driving circuit of backlight device with the protection module group |
| JP2008027688A (en) * | 2006-07-20 | 2008-02-07 | Sharp Corp | Surface light source device |
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