CN203086782U - LED illuminating controller, driver, illuminating device, and display device - Google Patents

LED illuminating controller, driver, illuminating device, and display device Download PDF

Info

Publication number
CN203086782U
CN203086782U CN2012206771095U CN201220677109U CN203086782U CN 203086782 U CN203086782 U CN 203086782U CN 2012206771095 U CN2012206771095 U CN 2012206771095U CN 201220677109 U CN201220677109 U CN 201220677109U CN 203086782 U CN203086782 U CN 203086782U
Authority
CN
China
Prior art keywords
led
levels
current
signal
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn - After Issue
Application number
CN2012206771095U
Other languages
Chinese (zh)
Inventor
宋振宇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
iWatt Integraged Circuits Technology Tianjin Ltd
Original Assignee
iWatt Integraged Circuits Technology Tianjin Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by iWatt Integraged Circuits Technology Tianjin Ltd filed Critical iWatt Integraged Circuits Technology Tianjin Ltd
Priority to CN2012206771095U priority Critical patent/CN203086782U/en
Application granted granted Critical
Publication of CN203086782U publication Critical patent/CN203086782U/en
Anticipated expiration legal-status Critical
Withdrawn - After Issue legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

Landscapes

  • Circuit Arrangement For Electric Light Sources In General (AREA)

Abstract

The utility model provides a light emitting diode (LED) illuminating controller, a driver, an illuminating device, and a display device. According to the embodiments provided by the utility model, the LED illuminating controller comprises one or more output ends, each of which can be connected with an LED channel regulator; an illumination controller, which can be used to generate digital current level signals and current level output control signals; and a signal conversion unit, which can be used to convert the digital current level signals into analog current level signals, and can be used to output the analog current level signals by one output end or one of the output ends based on the current level output control signals. According to the embodiments provided by the utility model, the device size and the power dissipation of the LED driver can be effectively reduced, therefore the LED illuminating controller is especially suitable for the application requiring the small device size and/or the small power dissipation.

Description

LED light emission controller, driver, lighting apparatus and display device
Technical field
Execution mode of the present utility model relates to the technical field of light-emitting diode (LED) illumination, the lighting apparatus and the display device that relate more particularly to a kind of LED light emission controller, led driver and comprise led driver.
Background technology
LED has been widely used in the multiple electronic application, the backlight and photoflash lamp of for example architectural lighting, vehicle head taillight, liquid crystal display etc.With compare as the conventional light source of incandescent lamp and fluorescent lamp and so on, LED has many remarkable advantages.These advantages comprise efficient height, good directionality, color stability height, reliability height, the life-span is long, volume is little and have environmental safety.
LED itself is a kind of current-driven apparatus, and therefore the electric current of regulating by LED is one of important control technology.In order to drive a big led array from a direct current (DC) voltage source, need usually to use such as boost or the buck-boost transducer the DC-DC switch power converter so that provide head rail (top rail) voltage for a plurality of LED strings.In the LCD (LCD) of using LED-backlit is used, use controller to control a plurality of LED strings usually, and each LED string all have independently electric current setting.Therefore this controller can be controlled the brightness of LCD different piece independently.In addition, this controller can also open or cut out the different piece of LCD in mode regularly.
By Xuecheng, people such as Jin have proposed a kind of self-adaptive switch pattern led driver in the U.S. Patent application 12/558,275 of application on September 11st, 2009.For purpose of explanation, in Fig. 1, schematically show self-adaptive switch pattern led driver according to this scheme.
As shown in Figure 1, this self-adaptive switch pattern led driver 300 comprises power management module 301, and it for example is a boost converter.This power management module 301 is configured to and receives input voltage vin and produce the output voltage V boost that is used to drive each LED string.In each LED passage, LED goes here and there 302 and channel switch Q PBe connected in series this channel switch Q POpen or close corresponding LED string 302 according to the duty cycle signals that applies on it.In addition, in each LED passage, also be connected to channel switch Q such as the passages regulate device 304 of low dropout regulator (LDO) P, and be configured to the levels of current signal that receives programming, and according to the electric current of the levels of current Signal Regulation of programming through the LED string.
Illumination controller 310 can be configured to produce a corresponding program current horizontal signal in the finite aggregate with programmable current level at each LED string, so that control electric current by corresponding LED string by each passages regulate device.Illumination controller 310 produces the duty cycle signals as the function of the levels of current of programming in addition, and this duty cycle signals is provided for channel switch Q PSo that the unlatching of control LED string or close.Illumination controller 310 can be provided with the electric current of different programmings for the different LED string, and different duty ratios is set for each LED string, with current difference between the compensation LED string and different I-E characteristics, can drive a plurality of LED strings thus with different I-E characteristics.
Shown in self-adaptive switch pattern led driver 300 in, illumination controller 310 is digital devices, its generation be the signal of digital form, and are analogue devices as the operational amplifier 306 of the parts among the LDO, it needs the signal of analog form to import as it.For this reason, in circuit shown in Figure 1, adopted a DAC circuit at each passages regulate device, so that the levels of current conversion of signals of the digital form that illumination controller 310 is produced becomes the levels of current signal of analog form and offers passages regulate device 304, to be regulated the electric current by corresponding LED string by it.
Yet along with the increase of LED number of active lanes, the circuit size and the power dissipation of self-adaptive switch pattern led driver all will sharply increase.For this reason, exist in this area for circuit size that reduces led driver and the demand that reduces power dissipation.
The utility model content
In view of this, this paper has proposed a kind of new LED Driving technique so that solve to the small part or alleviate the subproblem at least that exists in the prior art.
According to first aspect of the present utility model, provide a kind of LED light emission controller.This LED light emission controller can comprise: one or more outputs, each described output can be operated to be connected to a LED passages regulate device; The illumination controller can be operated levels of current signal and levels of current output control signal to produce digital form; And signal conversion unit, can grasp the levels of current signal that becomes analog form with levels of current conversion of signals with described digital form, and based on described levels of current output control signal, at the levels of current signal of the described analog form of one of them place's output of described one or more outputs.
In one embodiment, described signal conversion unit can comprise: digital to analog converter is configured to the levels of current conversion of signals of described digital form is become the levels of current signal of described analog form; And one or more samplings and holding unit, each described sampling can be operated to be connected to an output with the output that keeps list, and can operate with levels of current output control signal based on input, levels of current signal to described analog form is sampled, and keeps the levels of current signal sample.
In another embodiment, each value that can be configured in response to the levels of current of described input output control signal of described one or more sampling and holding unit is low, levels of current signal to described analog form is sampled, and be height in response to the value of the levels of current of described input output control signal, the levels of current signal of described analog form is kept.
In another execution mode, the number of described digital to analog converter is less than the number of described sampling and holding unit.
In another execution mode, the number of described digital to analog converter is 1.
In another embodiment, wherein said one or more sampling and holding unit be following wherein any one or multiple: the mos field effect transistor sampling holder; The double buffering sampling holder; Double buffering sampling holder with complementary metal oxide semiconductor switch; The feedback sample retainer; Feedback sample retainer with input amplifier stabilizing circuit; The integration sampling retainer; Sampling holder based on miller capacitance; And switching capacity sampling holder.
According to second aspect of the present utility model, provide a kind of LED driver.This led driver can comprise: according to the described LED light emission controller of disclosed first aspect; And one or more LED passages regulate devices, it is electrically connected with described one or more outputs of described LED light emission controller respectively, and can operate with the levels of current signal based on the analog form of importing, and regulates the electric current of corresponding LED string.
In one embodiment, described led driver can comprise a LED channel switch at each LED string, described illumination controller can further be configured to produce duty cycle signals, so that controlled the opening and closing of corresponding LED string by described LED channel switch.
In another embodiment, described illumination controller can be configured to produce different levels of current signal and different duty cycle signals at a plurality of LED strings, so that described a plurality of LED string has essentially identical average current level.
In an execution mode again, described led driver can comprise power management module, is configured to be provided under the control of described illumination controller based on input voltage the output voltage of driving LED string.
In another execution mode, described power management module can comprise stepup transformer, reducing transformer and boost-reducing transformer one of them.
According to the third aspect of the present utility model, a kind of lighting apparatus is provided, comprise led driver according to second aspect of the present disclosure.
According to fourth aspect of the present utility model, a kind of display device is provided, it comprises according to the described lighting apparatus of the third aspect of the present disclosure.
By the execution mode that this paper provided, can reduce equipment size, manufacturing cost and the power dissipation of led driver effectively, make it be particularly suitable for the application that requires less equipment size and/or smaller power to dissipate thus.
Description of drawings
By shown execution mode in conjunction with the accompanying drawings is elaborated, above-mentioned and other features of the present disclosure will be more obvious, and in disclosure accompanying drawing, identical label is represented same or analogous parts.In the accompanying drawings:
The circuit diagram of the schematically illustrated a kind of self-adaptive switch pattern led driver of the prior art of Fig. 1.
Fig. 2 schematically shows the block diagram according to the led driver of an execution mode of the present utility model.
Fig. 3 schematically shows the detailed circuit schematic according to the led driver of an execution mode of the present utility model.
Fig. 4 schematically shows the sequential chart according to the signal that is used for the driving LED string of an execution mode of the present utility model.
Fig. 5 A to Fig. 5 H schematically illustrates can be at the sampling of execution mode use of the present utility model and the exemplary circuit figure of holding unit.
Fig. 6 schematically illustrates the flow chart according to the method that is used for driving LED of an execution mode of the present utility model.
Embodiment
Hereinafter, will be described in detail with reference to the attached drawings each illustrative embodiments of the present utility model.Should be noted that these accompanying drawings and describing what relate to only is preferred implementation as example.Should be noted that,, be easy to dream up the replacement execution mode of structure disclosed herein and method, and can under the situation of the principle that does not break away from the claimed utility model of the utility model, use these alternate embodiments according to describing subsequently.
Should be appreciated that providing these illustrative embodiments only is for those skilled in the art can being understood better and then realize the utility model, and be not to limit scope of the present utility model by any way.
Next, with the basic framework that at first is described with reference to Figure 2 according to the led driver of an execution mode of the present utility model.
As shown in Figure 2, in an example, led driver can comprise: power management module 301, one or more LED strings 302, one or more channel switchs 303, one or more passages regulate devices 304, LED light emission controller 350 and feedback loop 330.And LED light emission controller 350 can comprise illumination controller 310 and signal conversion unit 320.
Power management module 301 receives input voltage vin and under the control of the control signal 314 that illumination controller 310 provides, input voltage vin is converted to the appropriate voltage Vdrive that is suitable for the driving LED string.This power management module 301 can be stepup transformer, reducing transformer and boost-reducing transformer wherein any one.Certainly, the utility model is not limited only to this, and power management module 301 also can adopt any other suitable form.
Each LED string comprises a plurality of LED that are connected in series.One end of each LED string is connected with the output of power management module 301, and the other end is connected with corresponding LED channel switch 303.LED channel switch 303 for example is pulse width modulation (PWM) transistor.Each channel switch all can independently be controlled the brightness of corresponding LED string 302 according to the PWM duty cycle signals 308 that illumination controller 310 provides.
One or more passages regulate devices 304 link to each other with one or more channel switchs 303 respectively.Passages regulate device 304 is connected to an output of signal conversion unit 320 separately.And signal conversion unit 320 is connected to illumination controller 310.
Illumination controller 310 also produces the levels of current signal 309 and the corresponding levels of current output control signal 326 that are used for control channel adjuster 304 except generation is used for the duty cycle signals 308 of control channel switch 303.This levels of current signal 309 is digital forms, it converts the levels of current signal 309 ' of analog form to via signal conversion unit 309, and signal conversion unit 309 is under the control of levels of current output control signal 326, output is with the levels of current signal 309 ' of this analog form, so that this levels of current signal 309 ' is offered corresponding passages regulate device 304 on its corresponding lead-out terminal.
Passages regulate device 304 for example is linear differential pressure regulator (LDO), and its levels of current signal 309 ' based on the analog form of input is regulated the electric current by corresponding LED string, thereby controls the illumination output of corresponding LED string.
Feedback loop 330, electric current output that can each passages regulate device 304 of sensing, and provide it to illumination controller 310 is so that illumination controller 310 can be provided with the level of electric current to the small part for each passages regulate device 394 based on this feedback signal.
In addition, in execution mode of the present utility model, adopted a brand-new LED light emission controller 350, particularly comprising signal conversion unit 320.This signal conversion unit 320 can adopt less digital-to-analogue conversion device to carry out the digital-to-analogue conversion of signal, and under the control of the levels of current output control signal 326 that illumination controller 310 produces, the levels of current signal is offered corresponding passages regulate device.Owing to significantly reduced the use of the DAC device that size is big, power dissipation is big, therefore can significantly reduce the equipment size and the power dissipation of whole LED driver, make it be specially adapted to the application that requires smaller power to dissipate thus.
Hereinafter, will describe detailed circuit structure in detail with reference to figure 3 according to each part of the led driver of an execution mode of the present utility model.
Power management module
With reference to figure 3, in this embodiment, power management module is a boost converter 301.The output voltages that this boost converter 301 receives input voltage vin and provides through adjusting for LED string 302.In a kind of execution mode of the present utility model, boost converter 301 comprises inductor L1, diode D1, capacitor C1, switch Q B(for example, nmos pass transistor), resistor R 1, R2 and boost pressure controller 316.Boost pressure controller 316 comes control switch Q based on from the control signal 314 of illumination controller and the output voltage V boost that senses BDuty ratio.Owing to becoming reverse bias, diode D 1 makes switch Q BDuring disconnection, be stored among the inductor L1 from the input power of supply voltage Vin.Owing to becoming forward bias, diode D1 makes switch Q BWhen closed, two ends provide output voltage V boost thereby input power is passed to capacitor C1.Output voltage V boost is applied to each LED string 302, so that the electric current by the LED string to be provided.
Resistor R 1 and resistor R 2 constitute a voltage divider.Boost pressure controller 316 comes sensing output voltage V boost via this voltage divider, and controls Q based on the voltage of sensing BOpening and closing so that regulate output voltage V boost.Boost pressure controller 316 can adopt in the multiple known modulation technique any one to come control switch Q BOpening and closing state and duty ratio, such as pulse width modulation (PWM) or pulse frequency modulated (PFM).PWM and PFM are the routine techniquess of application controls switch power converter, and they are respectively applied for by controlling and driving switch Q BThe corresponding width of output driving pulse and frequency realize that power output regulates.This feedback loop allows boost converter 301 that output voltage V boost is remained on level by the set programming of boost pressure controller 316.
The illumination controller
Illumination controller 310 is parts according to the LED light emission controller of an embodiment.These illumination controller 310 each LED passages of monitoring, and peak current and PWM duty ratio are set, to keep the brightness coupling between the LED passage and to optimize power efficiency.Illumination controller 310 output control signals 308,309,318,314,326 are to control corresponding PWM switch Q P, LDO 304, multiplexer 311, boost converter 301 and SH 322.Illumination controller 310 also receives from the feedback signal 315 of LDO 304 and brilliance control input 317.
Control signal 309 provides the levels of current signal 309 of digital form, this signal 309 will be converted into the signal 309 ' of analog form by signal conversion unit 320 (more specifically DAC 324), so that the analog reference voltage Vref by the program current of LED string 302 is set.In addition, it also produces levels of current output control signal 326, so that control signal converting unit 320 makes it that signal 309 ' is exported to corresponding LDO 304.
In an execution mode of the present utility model, the control signal 309 (that is levels of current signal) that illumination controller 310 generates can be the 3 bit DAC words that allow 8 kinds of possibility programmable currents.For example, in an execution mode of the present utility model, the electric current of each LED passage can be provided with in the scope of 54mA at 40mA with the increment of 2mA.Illumination controller 310 can be the electric current that each LED passage is determined programming during calibration phase.DAC 324 can have enough precision, so that extraordinary coupling can be provided between the LED passage.Levels of current output control signal 326 for example can be 1 bit signal, and it can have 0 or 1 value.Can when generating levels of current signal 309, generate a levels of current output signal 326, this levels of current signal be offered which LDO 304 with alert signal converting unit 320.Like this, illumination controller 310 just can be controlled each LED passage independently, so that can regulate different LED passages according to different program currents.
Each control signal 308 is recently digitally controlled the PWM switch Q of each LED passage according to the PWM duty of LED passage PIllumination controller 310 is that each LED passage is determined the PWM duty ratio as the function of the electric current of programming at calibration phase.Equally, illumination controller 310 can be controlled the duty ratio of each LED passage independently, so that can recently dispose different LED passages with different PWM duties.For a given LED passage, the electric current of PWM duty ratio and programming is determined the brightness output of LED in the LED passage jointly.In according to execution mode of the present utility model, can produce different levels of current signal and different duty cycle signals at a plurality of LED strings, so that described a plurality of LED string has essentially identical average current level
Control signal 318 will be controlled the switch of multiplexer 311.Illumination controller 310 is by the selection wire 318 of switch multiplexing device 311, monitors feedback signal from the different LED passage in order via ADC 313.
Control signal 314 can be controlled at the boost pressure controller 316 that calibration phase is provided with supply voltage Vboost.Control signal 314 can be provided with Vboost with any several usual manners, such as, by add an electric current at the node place of feedback resistor R1, R2, perhaps by sending the digital massage that a reference that causes boost pressure controller 316 inside changes.
Illumination controller 310 receives the relative brightness input BI that specifies each passage n nOutside brightness input 317.In one embodiment, brightness input BI nThe desirable relative brightness of each LED passage n is expressed as percentage (for example, the BI of a predefined maximum brightness 1=60%, BI 2=80%, BI 3=100% etc.).Illumination controller 310 uses brightness input BI nAs the baseline duty ratio of passage, because the brightness of passage output is directly proportional with its duty ratio.Thereby, for example, 60% brightness input BI nExpression passage n's is the baseline duty ratio of high duty ratio (corresponding to maximum brightness) 60%.But illumination controller 310 is producing driving PWM switch Q P Duty cycle signals 308 time revise this baseline duty ratio with a compensating factor, to compensate the current difference between the known LED passage and to keep desirable relative brightness.The duty cycle signals 308 of this compensating factor and generation thereof can be determined in the calibration sections.
Linear differential pressure regulator (LDO)
LDO 304 regulates electric current by LED string 302 according to the levels of current of the programming of each LED passage.Each LDO 304 comprises operational amplifier 306, sense resistor R S, and transmission transistor Q L(for example, nmos pass transistor).Transmission transistor Q LWith sense resistor R SBe serially connected in PWM switch Q PAnd between the earth terminal.The output of operational amplifier 306 is connected to transmission transistor Q LGrid with the electric current of control by LDO 304.Operational amplifier 306 receives output signal from SH 322 as positive input signal Vref, and via being derived from transmission transistor Q LThe negative feedback loop receiving feedback signals of source electrode as negative input signal Vsense.
The feedback loop that LDO 304 comprises is via electric current and the control transmission transistor Q of Vsense sensing by the LED string LSo that the electric current of sensing is remained on the levels of current of the programming that is provided with by Vref.Operational amplifier 306 compares Vref and Vsense.If Vref is higher than Vsense, operational amplifier 306 increases are applied to transmission transistor Q so LGrid voltage, to increase by sense resistor R SElectric current with LED string 302 is stabilized in Vref until it.Be higher than Vref if VsenSe becomes, then operational amplifier 306 reductions are applied to transmission transistor Q LGrid voltage, to reduce to pass through R SElectric current and cause Vsense to descend, be stabilized in Vref until it.Thus, LDO 304 uses a feedback loop that Vsense is remained on Vref, thus will by LED go here and there 302 electric current remain on one with the proportional fixed numbers of Vref.
Signal conversion unit
Signal conversion unit 320 illustrates with the single-point line in Fig. 3, and it is a part according to the LED light emission controller of an embodiment.Signal conversion unit 320 can be operated the levels of current signal 309 ' that converts analog form with the levels of current signal 309 with digital form to, and based on described levels of current output control signal 326, at the levels of current signal 309 ' of one of them place's output analog form of one or more outputs.
In execution mode as shown in Figure 3, this signal conversion unit 320 can comprise a DAC 324 and a plurality of SH 322.DAC 324 is connected to the levels of current signal output terminal of illumination controller 310 to receive the levels of current signal 309 ' of digital form.The input of each SH322 all is connected to the output of DAC 324, so that can receive the levels of current signal 309 ' through the analog form of DAC 324 conversions.The output of each SH 322 is connected to corresponding passages regulate device 304, so that levels of current signal 309 ' is provided to the passages regulate device 304 that links to each other.In addition, the signal input end of each SH 322 also is connected to illumination controller 310, to receive the levels of current output control signal 326 from illumination controller 310.
DAC 324 can convert the levels of current signal 309 from the digital form of illumination controller 310 to the levels of current signal 309 ' of analog form.As previously mentioned, the levels of current signal of this digital form can be the 8 bit DAC words that (but being not limited to) allows 8 kinds of possibility programmable currents.DAC 324 can convert these 8 DAC words to and a corresponding corresponding analog signal 309 ' of levels of current.Each can operate SH 322 with the levels of current output control signal 326 based on input, the levels of current signal 309 ' of the analog form of DAC 324 outputs is sampled, and keep the levels of current signal that samples at its output.Like this, just the levels of current signal at the special modality adjuster can be outputed to corresponding passages regulate device.
Fig. 4 schematically shows the sequential chart according to the signal that is used for the driving LED string of an execution mode of the present utility model.Wherein schematically show the levels of current signal that illumination controller 310 sends to DAC 324 with " data ", it for example comprises DATA1, DATA2 ..., DATAN, each data pin is to a LED passage.Be used to control each sampling retentive control signal (being levels of current output control signal 326) of each SH 322, respectively by SH1, SH2 ..., SHN illustrates.
As shown in the figure, at DATA1, the sampling inhibit signal SH1 that illumination controller 310 generates at corresponding SH 322.The time that control SH 322 samples should be in the duration of DATA1, so that make it can sample the levels of current signal of corresponding analog form.When the value of SH1 when low, the output of 322 couples of DAC of the SH (t that samples sDuring this time), and when the value at SH2 when being high, SH 322 keeps the signal (t that samples in its output hDuring this time).Similarly, at DATA2, generate sampling inhibit signal SH2 at corresponding SH 322.Value in response to SH2 is low, and the output of corresponding 322 couples of DAC of SH is sampled, and be height in response to the value of SH2, and the signal that samples is kept.For other signals, situation also is similar.
By such mode, just the levels of current signal 309 of the digital form that illumination controller 310 can the be produced signal 309 that converts analog form to ' and offers corresponding passages regulate device 304, and then regulates the electric current by each LED string.
In the LED light emission controller in one embodiment, significantly less than the number of SH, most preferably, the number of DAC is 1 to the number of DAC.That is,, can only adopt a DAC will become the levels of current signal of analog form at the levels of current conversion of signals of the digital form of each passages regulate device for several SH 322.Because the size of sampling and holding unit and power dissipation are significantly less than DAC, therefore identical with number of active lanes with adopting number DAC realizes that the prior art of parallel digital-to-analogue conversion compares, this example can significantly reduce equipment size and power dissipation, makes the led driver of this embodiment be particularly useful for the application of less equipment size of requirement and/or smaller power dissipation thus.
Below, will the sampling that can use and the example of holding unit be described with reference to figure 5A to Fig. 5 F in the utility model execution mode.
Fig. 5 A shows mos field effect transistor (MOSFET) sampling holder, wherein adopts switch mosfet and capacitor to realize sampling and keeping functional.Fig. 5 B shows the schematic circuit diagram of double buffering sampling holder, and wherein this sampling hold circuit has input buffer and output buffer, so that realize low rate of descent in the maintenance process.Fig. 5 C shows the double buffering sampling holder of (COMS) switch that has complementary metal oxide semiconductors (CMOS), wherein uses two cmos switches to come single switch among the alternate figures 5B.Fig. 5 D shows the feedback sample retainer, and wherein the output of sampling holder is fed back to input buffer and output buffer respectively, keeps output to realize accurate more sampling.Fig. 5 E shows the feedback sample retainer with input amplifier stabilizing circuit, has wherein adopted output stability during a simple stabilizing circuit provides maintenance at input amplifier.Fig. 5 F shows the integration sampling retainer, and it adopts integral principle to realize that sampling keeps function, so that control switch constantly and the feedthrough of electric charge better.Fig. 5 G and Fig. 5 H show the circuit of switching capacity sampling holder, and wherein Fig. 5 G shows the basic structure of switching capacity sampling holder, and Fig. 5 H shows a kind of circuit structure of switching capacity sampling holder commonly used.In addition, can also use always sampling holder based on miller capacitance.
Need to prove that the sampling holder that provides just for exemplary purposes herein.In fact, except the sampling holder examples of circuits that provides, also can adopt the sampling hold circuit of any other appropriate configuration in the utility model execution mode herein.The operation principle of these sampling holders is known, is not therefore giving unnecessary details herein.
In addition, this specification also provides a kind of method that is used for driving LED.Describe in detail below with reference to Fig. 6.As shown in Figure 6, at first at step S601, for example produce the levels of current signal and the levels of current output control signal of digital form by illumination controller 310.Then, can for example by DAC, the levels of current conversion of signals of described digital form be become the levels of current signal of analog form at step S602.Then, at step S603,, export the levels of current signal of analog form based on the levels of current output control signal that produces at one of them place of one or more outputs, so that regulate electric current by the LED string by for example sampling and holding unit.
Particularly, can export control signal, the levels of current signal of described analog form is sampled, and keep the levels of current signal sample based on levels of current.For example, can be low in response to the value of the levels of current output control signal of importing, levels of current signal to analog form is sampled, and be height in response to the value of the levels of current output control signal of input, and the levels of current signal of analog form is kept.
In addition, can also generate duty cycle signals, and control the opening and closing of corresponding LED string according to described duty cycle signals.In according to execution mode of the present utility model, can produce different levels of current signal and different duty cycle signals at a plurality of LED strings, so that described a plurality of LED string has essentially identical average current level.
Need to prove,, can join above in conjunction with the specific descriptions of Fig. 2 to Fig. 5 to the operation of each parts in the led driver among the embodiment about the detail operations of the method that is used for driving LED.
Also need to prove, in above-mentioned detailed description, only the part relevant with the utility model in led drive circuit and the driving governor is described, so that its get those skilled in the art can be more fully the content of some embodiment, for other parts, for example can be with reference to U.S. Patent application 12/558,275, it is included in this in full with as a reference.
In addition, this specification provides a kind of lighting apparatus, and it can comprise that one end of each LED string is connected with led driver according to previously described led driver and one or more LED string, and the other end is connected with the driving voltage input.This specification also provides a kind of display device, and it can comprise according to disclosed lighting apparatus.
By reading the content of this specification, those of skill in the art will understand other alternate design of this self-adaptive switch pattern led driver.Therefore, though, should be appreciated that this specification is not limited to precise structure disclosed herein and parts in this specific implementations and application that illustrates and described this specification for example.And, for a person skilled in the art, under the situation of utility model essence that does not break away from claims and limited and scope, various modifications, change and change that arrangement, operation and the details aspect of method of the present utility model disclosed herein and device are carried out also all are conspicuous.
In addition, though described the utility model, should be appreciated that the utility model is not limited to disclosed embodiment with reference to some embodiments.The utility model is intended to be encompassed in the interior included various modifications and the equivalent arrangements of spirit and scope of claims.The scope of claims meets the most wide in range explanation, thereby comprises all such modifications and equivalent structure and function.

Claims (13)

1. a LED light emission controller is characterized in that, comprising:
One or more outputs, each described output can be operated to be connected to a LED passages regulate device;
The illumination controller can be operated levels of current signal and levels of current output control signal to produce digital form; And
Signal conversion unit, can grasp the levels of current signal that becomes analog form with levels of current conversion of signals with described digital form, and based on described levels of current output control signal, at the levels of current signal of the described analog form of one of them place's output of described one or more outputs.
2. LED light emission controller according to claim 1 is characterized in that, described signal conversion unit comprises:
Digital to analog converter is configured to the levels of current conversion of signals of described digital form is become the levels of current signal of described analog form; And
One or more samplings and holding unit, each described sampling can be operated to be connected to an output with the output that keeps list, and can operate with levels of current output control signal based on input, levels of current signal to described analog form is sampled, and keeps the levels of current signal sample.
3. LED light emission controller according to claim 2, it is characterized in that, each value that is configured in response to the levels of current of described input output control signal of described one or more sampling and holding unit is low, levels of current signal to described analog form is sampled, and be height in response to the value of the levels of current of described input output control signal, the levels of current signal of described analog form is kept.
4. LED light emission controller according to claim 2 is characterized in that the number of described digital to analog converter is less than the number of described sampling and holding unit.
5. LED light emission controller according to claim 4 is characterized in that, the number of described digital to analog converter is 1.
6. according to each described LED light emission controller of claim 1 to 5, it is characterized in that, described one or more samplings and holding unit be following wherein any one or multiple:
The mos field effect transistor sampling holder;
The double buffering sampling holder;
Double buffering sampling holder with complementary metal oxide semiconductor switch;
The feedback sample retainer;
Feedback sample retainer with input amplifier stabilizing circuit;
The integration sampling retainer;
Sampling holder based on miller capacitance; And
The switching capacity sampling holder.
7. a LED driver is characterized in that, comprising:
According to each described LED light emission controller of claim 1 to 6; And
One or more LED passages regulate devices, it is electrically connected with described one or more outputs of described LED light emission controller respectively, and can operate with the levels of current signal based on the analog form of importing, and regulates the electric current of corresponding LED string.
8. led driver according to claim 7, it is characterized in that, described led driver comprises a LED channel switch at each LED string, and described illumination controller further is configured to produce duty cycle signals, so that controlled the opening and closing of corresponding LED string by described LED channel switch.
9. led driver according to claim 8, it is characterized in that, described illumination controller is configured to produce different levels of current signal and different duty cycle signals at a plurality of LED strings, so that described a plurality of LED string has essentially identical average current level.
10. led driver according to claim 7 is characterized in that, further comprises power management module, is configured to be provided under the control of described illumination controller based on input voltage the output voltage of driving LED string.
11. led driver according to claim 10, wherein said power management module comprise stepup transformer, reducing transformer and boost-reducing transformer one of them.
12. a lighting apparatus is characterized in that, comprising:
According to each described led driver of claim 7 to 11; And
One or more LED strings, an end of each LED string is connected with led driver, and the other end is connected with the driving voltage input.
13. a display device is characterized in that, comprises lighting apparatus according to claim 12.
CN2012206771095U 2012-12-06 2012-12-06 LED illuminating controller, driver, illuminating device, and display device Withdrawn - After Issue CN203086782U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2012206771095U CN203086782U (en) 2012-12-06 2012-12-06 LED illuminating controller, driver, illuminating device, and display device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2012206771095U CN203086782U (en) 2012-12-06 2012-12-06 LED illuminating controller, driver, illuminating device, and display device

Publications (1)

Publication Number Publication Date
CN203086782U true CN203086782U (en) 2013-07-24

Family

ID=48832577

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2012206771095U Withdrawn - After Issue CN203086782U (en) 2012-12-06 2012-12-06 LED illuminating controller, driver, illuminating device, and display device

Country Status (1)

Country Link
CN (1) CN203086782U (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103857140A (en) * 2012-12-06 2014-06-11 艾尔瓦特集成电路科技（天津）有限公司 LED light-emitting controller, driver, drive method, illuminating equipment and display equipment
CN104270861A (en) * 2014-09-30 2015-01-07 成都芯源系统有限公司 LED driver, control circuit and LED driving method
WO2017096664A1 (en) * 2015-12-08 2017-06-15 深圳市华星光电技术有限公司 Driver circuit
CN111145685A (en) * 2020-02-20 2020-05-12 Tcl华星光电技术有限公司 LED backlight driving module and display device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103857140A (en) * 2012-12-06 2014-06-11 艾尔瓦特集成电路科技（天津）有限公司 LED light-emitting controller, driver, drive method, illuminating equipment and display equipment
CN103857140B (en) * 2012-12-06 2016-09-21 戴泺格集成电路（天津）有限公司 LED light emission controller, driver, driving method, luminaire and display device
CN104270861A (en) * 2014-09-30 2015-01-07 成都芯源系统有限公司 LED driver, control circuit and LED driving method
WO2017096664A1 (en) * 2015-12-08 2017-06-15 深圳市华星光电技术有限公司 Driver circuit
US9842554B2 (en) 2015-12-08 2017-12-12 Shenzhen China Star Optoelectronics Technology Co., Ltd Driving circuit
CN111145685A (en) * 2020-02-20 2020-05-12 Tcl华星光电技术有限公司 LED backlight driving module and display device

Similar Documents

Publication Publication Date Title
KR101508418B1 (en) Predictive control of power converter for led driver
TWI477187B (en) Adaptive switch mode led system
KR101099991B1 (en) Adaptive switch mode led driver
US10278242B2 (en) Thermal and power optimization for linear regulator
TWI430705B (en) Driving apparatus of light emitted diode and driving method thereof
US8058810B2 (en) Method and system for high efficiency, fast transient multi-channel LED driver
US7224128B2 (en) Device for driving light emitting diode strings
US10136487B2 (en) Power optimization for linear regulator
KR101980089B1 (en) Dc-dc converter using hysteretic control and associated methods
CN203086782U (en) LED illuminating controller, driver, illuminating device, and display device
CN105896943A (en) Control circuit, control method and switching power supply employing control circuit
KR101778898B1 (en) Led backlight driving circuit and liquid crystal display
CN102543005A (en) Reference voltage generating circuit and LED driver circuit having the same therein
EP3017663B1 (en) Led driver with linearly controlled driving current
WO2018198594A1 (en) Led driver, and led drive circuit device and electronic equipment that use said led driver
CN101719345A (en) LED display system and control method thereof as well as driver of LED display system and control method thereof
CN103857140B (en) LED light emission controller, driver, driving method, luminaire and display device
KR20150014591A (en) Apparatus for driving the lamp using mcu
CN108541105B (en) LED driving system and method
TWI517758B (en) Driving apparatus of light emitted diode, driving method thereof and electronic device thereof
Kang et al. A new low voltage detecting method for multi-string LED BLU circuit
CN113329538B (en) LED driving circuit
KR20090068045A (en) Led driving apparatus
KR20090068103A (en) Led driving apparatus

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20130724

Effective date of abandoning: 20160921

C25 Abandonment of patent right or utility model to avoid double patenting