TWI517758B

TWI517758B - Driving apparatus of light emitted diode, driving method thereof and electronic device thereof

Info

Publication number: TWI517758B
Application number: TW102147588A
Authority: TW
Inventors: 徐國慶; 許慶勛; 張淙豪; 廖廷偉
Original assignee: 聯詠科技股份有限公司
Priority date: 2009-09-16
Filing date: 2009-09-16
Publication date: 2016-01-11
Also published as: TW201414358A

Description

發光二極體的驅動裝置、其驅動方法及其電子裝置 Light-emitting diode driving device, driving method thereof and electronic device thereof

本發明是有關於一種驅動方法，且特別是有關於一種發光二極體的驅動裝置、其驅動方法及其電子裝置。 The present invention relates to a driving method, and more particularly to a driving device for a light emitting diode, a driving method thereof, and an electronic device thereof.

發光二極體(Light Emitting Diode,LED)的體積小、省電且耐用，而且隨著製程的成熟，價格下降，近來以發光二極體做為光源之產品越來越普遍。此外，發光二極體工作電壓低(僅1.5-3V)、能主動發光且有一定亮度，亮度可用電壓或電流調節，同時具備耐衝擊、抗振動、壽命長(10萬小時)之特點，是以，發光二極體在各種終端設備中被廣泛使用，從汽車前照燈、交通信號燈、文字顯示器、看板及大螢幕視頻顯示器，到普通及建築照明和LCD背光等領域。 Light Emitting Diode (LED) is small, power-saving and durable, and as the process matures, the price drops. Recently, products using light-emitting diodes as light sources are becoming more and more popular. In addition, the light-emitting diode has a low operating voltage (only 1.5-3V), can actively emit light and has a certain brightness, and the brightness can be adjusted by voltage or current, and has the characteristics of impact resistance, vibration resistance and long life (100,000 hours). Light-emitting diodes are widely used in a variety of terminal equipment, from automotive headlights, traffic lights, text displays, billboards and large-screen video displays, to general and architectural lighting and LCD backlighting.

以發光二極體驅動電路而言，常用的調光方式之一為利用脈衝調變(pulse-width modulation,PWM)技術調整脈衝的責任週期(duty)，以此調整輸出級輸出至發光二極體的等效電流來調整發光二極體亮度。然而，在使用脈衝調變進行調光時，其輸出級輸出的電流切換動作如同開關一樣。而此電流切換動作會對輸出級的電壓進行極大的抽載變化，致使電壓會有過大漣波(ripple)的產生。同時，過大的漣波會對電路中的電感造成極大的磁場變化，以及電路中的電容會因為瞬間的電壓變化過大造成劇烈地振動(sharply vibrate)產生形變(shape-changing)，因此而產生音頻雜訊(audio noise)。 In the case of a light-emitting diode driving circuit, one of the commonly used dimming methods is to adjust the duty cycle of the pulse by pulse-width modulation (PWM) technology, thereby adjusting the output of the output stage to the light-emitting diode. The equivalent current of the body adjusts the brightness of the light-emitting diode. However, when dimming is performed using pulse modulation, its output The current switching action of the stage output is like a switch. This current switching action will greatly increase the voltage of the output stage, causing excessive voltage ripple. At the same time, too large chopping waves will cause great magnetic field changes in the inductance of the circuit, and the capacitance in the circuit will cause sharp-vibrate shape-changing due to excessive voltage changes in the transient, thus producing audio. Audio noise.

圖1A為一傳統發光二極體的驅動電路的系統示意圖。請參照圖1A，驅動電路100中包括電壓轉換器110、轉換迴路控制器120、放大器130、電壓選擇器140與由複數個電流驅動元件所組成的電流驅動單元150。電壓轉換器110接收電源電壓V_DD，且電壓轉換器110依據轉換迴路控制器120的輸出產生與電源電壓V_DD不同位準之操作電壓V_CC。放大器130的正輸入端接收參考電壓Vref，且其負輸入端接收電壓選擇器140所輸出的電壓，並依此輸出電壓以控制轉換迴路控制器120，其中參考電壓Vref為一固定值。電壓選擇器140用以選擇輸出發光二極體串列50_1~50_n其中之一負極端的電壓。發光二極體串列50_1~50_n之正極端接收操作電壓V_CC，發光二極體串列50_1~50_n之負極端分別透過開關S1~Sn與電流驅動單元150耦接，且透過負載電流i₁~i_n驅動發光二極體串列50_1~50_n發光，而開關S1~Sn同時依據調光信號進行開關的切換，以此進行調光的動作。 FIG. 1A is a schematic diagram of a system of a driving circuit of a conventional light emitting diode. Referring to FIG. 1A, the driving circuit 100 includes a voltage converter 110, a conversion loop controller 120, an amplifier 130, a voltage selector 140, and a current driving unit 150 composed of a plurality of current driving elements. The voltage converter 110 receives the power supply voltage V _DD , and the voltage converter 110 generates an operating voltage V _{CC that is} different from the power supply voltage V _DD according to the output of the conversion loop controller 120. The positive input terminal of the amplifier 130 receives the reference voltage Vref, and its negative input terminal receives the voltage output by the voltage selector 140, and accordingly outputs a voltage to control the conversion loop controller 120, wherein the reference voltage Vref is a fixed value. The voltage selector 140 is configured to select a voltage for outputting one of the negative terminals of the LED series 50_1~50_n. The positive terminal of the LED series 50_1~50_n receives the operating voltage V _CC , and the negative terminals of the LED series 50_1~50_n are coupled to the current driving unit 150 through the switches S1~Sn respectively, and the load current i _{1 is} transmitted. The ~i _n driving light-emitting diode series 50_1~50_n emit light, and the switches S1~Sn simultaneously switch the switches according to the dimming signal, thereby performing the dimming action.

圖1B為圖1A的驅動電流的時序圖。請參照圖1A及圖1B，在發光二極體驅動電路100中，常用脈衝調變技術來調整供應負載電流i₁~i_n的時間t₁來調整發光二極體的發光的亮度。換言之，在固定的週期T中，時間t₁越長則發光二極體的亮度會越高；反之，時間t₁越短則發光二極體的亮度會越低。然而，在使用脈衝調變進行調光時，開關S1~Sn的切換動作所造成的負載電流i₁~i_n的變化。上述負載電流i₁~i_n的變化會使操作電壓V_CC有著極大的抽載變化，致使電壓轉換器110輸出的操作電壓V_CC會有過大漣波的產生。同時，電壓轉換器110輸入電流也會有極大的瞬間變化，除了讓電壓轉換器110內的電感造成極大的磁場變化，也讓電壓轉換器110內的穩壓電容因為瞬間電壓變化過大而劇烈地振動且產生形變，因此而產生音頻雜訊。此外，以驅動電路100而言，在進行調光時，其開關S1~Sn會同時進行切換，以同時作負載電流i₁~i_n的切換動作，而電流切換動作會造成嚴重的電磁干擾(Electromagnetic Disturbance,EMI)。 FIG. 1B is a timing diagram of the driving current of FIG. 1A. Referring to FIG. 1A and FIG. 1B, in the LED driving circuit 100, a pulse modulation technique is commonly used to adjust the time t _{1 of} supplying the load currents i ₁ to i _n to adjust the luminance of the light emitted by the LED. In other words, in a fixed period T, the longer the time t _{1 ,} the higher the brightness of the light-emitting diode; conversely, the shorter the time t _{1 , the} lower the brightness of the light-emitting diode. However, when dimming is performed using pulse modulation, the load currents i ₁ to i _n caused by the switching operations of the switches S1 to Sn are changed. The load current i ₁ ~ i _n the change in the operating voltage V _CC will have a great change in pumping the carrier, so that the output of the voltage converter 110 generates the operating voltage V _CC of an excessive ripple. At the same time, the input current of the voltage converter 110 also has a great instantaneous change, except that the inductance in the voltage converter 110 causes a great magnetic field change, and the voltage regulator capacitor in the voltage converter 110 is drastically changed due to excessive voltage changes. It vibrates and deforms, thus producing audio noise. In addition, in the driving circuit 100, when dimming is performed, the switches S1 to Sn are switched at the same time to simultaneously switch the load currents i ₁ to i _n , and the current switching action causes severe electromagnetic interference ( Electromagnetic Disturbance, EMI).

本發明提供一種發光二極體的驅動裝置、其驅動方法及其電子裝置，可以抑制音頻雜訊及電磁干擾。 The invention provides a driving device for a light emitting diode, a driving method thereof and an electronic device thereof, which can suppress audio noise and electromagnetic interference.

本發明的發光二極體的驅動方法，適用於一驅動裝置。驅動方法包括下列步驟。偵測驅動裝置是否進行調光。若驅動裝置被偵測到進行調光，判斷用於調光控制的一既定要求是否滿足。當用於調光控制的既定要求未滿足時，調整多個驅動電流個別的電流大小，並且在一週期的全部時間中輸出各這些驅動電流。當用於調光控制的既定要求未滿足時，分別在一週期的部分時間中輸出各這些驅動電流。 The driving method of the light-emitting diode of the present invention is suitable for a driving device. The driving method includes the following steps. Detect if the drive is dimming. If the driving device is detected to perform dimming, it is determined whether a predetermined requirement for dimming control is satisfied. When the predetermined requirements for the dimming control are not satisfied, the individual currents of the plurality of driving currents are adjusted, and each of the driving powers is outputted in all the times of one cycle. flow. When the predetermined requirements for dimming control are not satisfied, each of these driving currents is output in a part of a period of time.

本發明的發光二極體的驅動方法，適用於一驅動裝置。驅動方法包括下列步驟。接收一調光信號。偵測驅動裝置是否進行調光。若驅動裝置被偵測到進行調光，依據調光信號的一責任週期調整多個驅動電流中個別的電流大小及輸出時間的至少其一，以使這些驅動電流於一週期中的總和實質上正比於調光信號的責任週期。 The driving method of the light-emitting diode of the present invention is suitable for a driving device. The driving method includes the following steps. Receive a dimming signal. Detect if the drive is dimming. If the driving device is detected to perform dimming, adjusting at least one of the plurality of driving currents and the output time according to a duty cycle of the dimming signal, so that the sum of the driving currents in one cycle is substantially It is proportional to the duty cycle of the dimming signal.

本發明的用以驅動多個發光二極體的驅動裝置，包括多個開關、一調光偵測器及一電流控制單元。開關用以耦接這些發光二極體。調光偵測器用以接收一調光信號及依據調光信號輸出一調光模式信號。電流控制單元用以依據調光模式信號及調光信號輸出多個控制信號，其中這些控制信號分別控制這些開關的導通狀態。 The driving device for driving a plurality of light emitting diodes of the present invention comprises a plurality of switches, a dimming detector and a current control unit. The switch is used to couple the light emitting diodes. The dimming detector is configured to receive a dimming signal and output a dimming mode signal according to the dimming signal. The current control unit is configured to output a plurality of control signals according to the dimming mode signal and the dimming signal, wherein the control signals respectively control the conduction states of the switches.

本發明的電子裝置，包括一如上述的驅動裝置及多個發光二極體。多個發光二極體，耦接且驅動於驅動裝置。 The electronic device of the present invention comprises a driving device as described above and a plurality of light emitting diodes. A plurality of light emitting diodes are coupled and driven to the driving device.

本發明的發光二極體的驅動方法，適用於一驅動裝置。驅動方法包括下列步驟。接收一調光信號。偵測驅動裝置是否進行調光。若驅動裝置進行調光，判斷調光信號的一責任週期是否小於一預設值。當調光信號的責任週期未小於預設值，依據調光信號調整多個驅動電流個別的電流大小，並且於一週期的全部時間輸出各這些驅動電流。當調光信號的責任週期小於預設值，各這些驅動電流分別於一週期的部分時間輸出。 The driving method of the light-emitting diode of the present invention is suitable for a driving device. The driving method includes the following steps. Receive a dimming signal. Detect if the drive is dimming. If the driving device performs dimming, it is determined whether a duty cycle of the dimming signal is less than a preset value. When the duty cycle of the dimming signal is not less than the preset value, the individual currents of the plurality of driving currents are adjusted according to the dimming signal, and each of the driving currents is outputted at all times of one cycle. When the duty cycle of the dimming signal is less than the preset value, each These drive currents are output at partial times of a cycle, respectively.

本發明的發光二極體的驅動裝置，包括一電流驅動單元、多個開關、一調光偵測器及一電流控制單元。電流驅動單元輸出多個驅動電流以個別驅動多個發光二極體。開關個別耦接於電流驅動單元及這些發光二極體之間，用以控制這些驅動電流是否輸出至這些發光二極體。調光偵測器接收一調光信號，且依據調光信號偵測驅動裝置是否進行調光且偵測調光信號的一責任週期是否小於一預設值，以輸出一調光模式信號。電流控制單元耦接調光偵測器及這些開關，並且控制這些開關的導通時間。當驅動裝置進行調光且調光信號的責任週期未小於預設值時，電流控制單元控制各這些開關為導通於一週期的全部時間，並且控制電流驅動單元依據調光信號調整這些驅動電流個別的電流大小。當驅動裝置進行調光且調光信號的責任週期小於預設值時，電流控制單元控制各這些開關為導通於一週期的部份時間。 The driving device of the light emitting diode of the present invention comprises a current driving unit, a plurality of switches, a dimming detector and a current control unit. The current driving unit outputs a plurality of driving currents to individually drive the plurality of light emitting diodes. The switches are individually coupled between the current driving unit and the light emitting diodes to control whether the driving currents are output to the light emitting diodes. The dimming detector receives a dimming signal, and detects whether the driving device performs dimming according to the dimming signal and detects whether a duty cycle of the dimming signal is less than a preset value to output a dimming mode signal. The current control unit is coupled to the dimming detector and the switches, and controls the on-time of the switches. When the driving device performs dimming and the duty cycle of the dimming signal is not less than a preset value, the current control unit controls each of the switches to be turned on for a full period of time, and the control current driving unit adjusts the driving currents according to the dimming signal. The current size. When the driving device performs dimming and the duty cycle of the dimming signal is less than a preset value, the current control unit controls each of the switches to be turned on for a part of a period of time.

基於上述，本發明的發光二極體的驅動裝置、其驅動方法及其電子裝置，當驅動裝置進行調光且調光信號的責任週期小於預設值時，則均勻分配各驅動電流於一週期中的輸出時間，並對應地調整各驅動電流的電流大小。當驅動裝置進行調光且調光信號的責任週期大於或等於預設值時，於週期中同時輸出驅動電流，並依據調光信號調整驅動電流的大小。藉此，可抑制驅動電流的總和變動過大所造成的音頻雜訊及電磁干擾。 Based on the above, the driving device of the light emitting diode of the present invention, the driving method thereof and the electronic device thereof, when the driving device performs dimming and the duty cycle of the dimming signal is less than a preset value, uniformly distributes the driving currents in one cycle. The output time in the middle, and adjust the current of each drive current correspondingly. When the driving device performs dimming and the duty cycle of the dimming signal is greater than or equal to the preset value, the driving current is simultaneously outputted in the cycle, and the driving current is adjusted according to the dimming signal. Thereby, it is possible to suppress audio noise and electromagnetic interference caused by excessive variation of the drive current.

為讓本發明的上述特徵和優點能更明顯易懂，下文特舉實施例，並配合所附圖式作詳細說明如下。 In order to make the above features and advantages of the present invention more apparent, the following is a special The embodiments are described in detail below in conjunction with the drawings.

50_1~50_n‧‧‧發光二極體串列 50_1~50_n‧‧‧Light diode series

100、200‧‧‧驅動裝置 100, 200‧‧‧ drive

110、210‧‧‧電壓轉換器 110, 210‧‧‧ voltage converter

120、220‧‧‧轉換迴路控制器 120, 220‧‧‧Switching loop controller

130、230‧‧‧放大器 130, 230‧ ‧ amplifier

140、240‧‧‧電壓選擇器 140, 240‧‧‧ voltage selector

150、250‧‧‧電流驅動單元 150, 250‧‧‧ current drive unit

260‧‧‧調光偵測器 260‧‧‧ dimming detector

261‧‧‧類比數位轉換器 261‧‧‧ Analog Digital Converter

262‧‧‧或閘 262‧‧‧ or gate

270‧‧‧電流控制單元 270‧‧‧ Current Control Unit

271、mux1‧‧‧多工器 271, mux1‧‧‧ multiplexer

272、274、275‧‧‧分散延遲產生器 272, 274, 275‧‧‧ Decentralized Delay Generator

273、276‧‧‧責任週期轉電壓轉換器 273, 276‧‧‧Responsible Cycle to Voltage Converter

D‧‧‧電流大小 D‧‧‧current size

S1~Sn、SW1~SWn‧‧‧開關 S1~Sn, SW1~SWn‧‧‧ switch

Sco1‧‧‧控制信號 Sco1‧‧‧ control signal

Smod‧‧‧調光模式信號 Smod‧‧‧ dimming mode signal

Sdim‧‧‧調光信號 Sdim‧‧‧ dimming signal

t₁、t₂‧‧‧時間 t ₁ , t ₂ ‧‧ ‧ time

T‧‧‧週期 T‧‧ cycle

GN‧‧‧增益信號 GN‧‧‧gain signal

i₁~i_n、I₁~I_n‧‧‧電流 i ₁ ~i _n , I ₁ ~I _n ‧‧‧ current

V_DD、V_CC、Vref、V_R‧‧‧電壓 V _DD , V _CC , Vref , V _R ‧‧‧ voltage

Vco1‧‧‧控制電壓 Vco1‧‧‧ control voltage

LPF1、LPF2‧‧‧低通濾波電路 LPF1, LPF2‧‧‧ low-pass filter circuit

R1、R2‧‧‧電阻 R1, R2‧‧‧ resistance

C1、C2‧‧‧電容 C1, C2‧‧‧ capacitor

ML1‧‧‧類比乘法器 ML1‧‧‧ analog multiplier

S301、S302、S311~S313‧‧‧根據本發明諸實施例的驅動方法的步驟 S301, S302, S311~S313‧‧‧ steps of the driving method according to embodiments of the present invention

圖1A為一傳統發光二極體的驅動裝置的系統示意圖。 FIG. 1A is a schematic diagram of a system of a driving device of a conventional light emitting diode.

圖1B為圖1A的驅動電流的時序圖。 FIG. 1B is a timing diagram of the driving current of FIG. 1A.

圖2A為根據本發明一實施例的驅動裝置的電路示意圖。 2A is a circuit diagram of a driving device in accordance with an embodiment of the present invention.

圖2B為圖2A的發光二極體串列的電流波形示意圖。 2B is a schematic diagram showing current waveforms of the LED array of FIG. 2A.

圖2C為圖2A的發光二極體串列的另一電流波形示意圖。 2C is a schematic diagram of another current waveform of the LED array of FIG. 2A.

圖2D為圖2A的驅動裝置與發光二極體串列的波形示意圖。 2D is a schematic diagram of a waveform of the driving device and the LED array of FIG. 2A.

圖2E為圖2A的電流控制單元耦接調光偵測器的電路示意圖。 2E is a circuit diagram of the current control unit of FIG. 2A coupled to the dimming detector.

圖2F為圖2E的責任週期轉電壓轉換器的電路示意圖。 2F is a circuit diagram of the duty cycle to voltage converter of FIG. 2E.

圖2G為圖2E的責任週期轉電壓轉換器的另一電路示意圖。 2G is another circuit diagram of the duty cycle to voltage converter of FIG. 2E.

圖2H為圖2A的電流控制單元耦接調光偵測器的另一電路示意圖。 2H is another circuit diagram of the current control unit of FIG. 2A coupled to the dimming detector.

圖2I為圖2A的電流控制單元耦接調光偵測器的再一電路示意圖。 2I is a schematic diagram of still another circuit of the current control unit of FIG. 2A coupled to the dimming detector.

圖3A為根據本發明一實施例的驅動方法的流程圖。 3A is a flow chart of a driving method in accordance with an embodiment of the present invention.

圖3B為根據本發明另一實施例的驅動方法的流程圖。 FIG. 3B is a flow chart of a driving method according to another embodiment of the present invention.

圖2A為根據本發明一實施例的驅動裝置的電路示意圖。請參照圖2A，驅動裝置200包括電壓轉換器210、轉換迴路控制器220、放大器230、電壓選擇器240、電流驅動單元250、調光偵測器260、電流控制單元270及開關SW1~SWn。調光偵測器260接收調光信號Sdim，以依據調光信號Sdim偵測驅動裝置200是否進行調光並據此輸出調光模式信號Smod。電流控制單元270依據調光模式信號Smod及調光信號Sdim輸出多個控制信號Sco1及控制電壓Vco1，以利用這些控制信號Sco1分別控制開關SW1~SWn導通與否，並且透過控制電壓Vco1控制電流驅動單元250調整驅動電流I₁~I_n的大小。 2A is a circuit diagram of a driving device in accordance with an embodiment of the present invention. Referring to FIG. 2A, the driving device 200 includes a voltage converter 210, a conversion loop controller 220, an amplifier 230, a voltage selector 240, a current driving unit 250, a dimming detector 260, a current control unit 270, and switches SW1 SWSWn. The dimming detector 260 receives the dimming signal Sdim to detect whether the driving device 200 performs dimming according to the dimming signal Sdim and outputs the dimming mode signal Smod accordingly. The current control unit 270 outputs a plurality of control signals Sco1 and a control voltage Vco1 according to the dimming mode signal Smod and the dimming signal Sdim, respectively, to control whether the switches SW1 SWSWn are turned on or not by using the control signals Sco1, and control the current driving through the control voltage Vco1. Unit 250 adjusts the magnitude of drive currents I ₁ ~I _n .

電壓轉換器210接收電源電壓V_DD，並依據轉換迴路控制器220輸出的調整信號產生與電源電壓V_DD不同位準之操作電壓V_CC。轉換迴路控制器220依據其所接收的電壓產生調整信號。放大器230的正輸入端接收參考電壓V_R，且其負輸入端接收電壓選擇器240所輸出的電壓，並依此輸出電壓至轉換迴路控制器220，其中參考電壓V_R可以為一固定值。電壓選擇器240用以選擇輸出發光二極體串列50_1~50_n其中之一負極端的電壓。發光二極體串列50_1~50_n之正極端接收操作電壓V_CC，發光二極體串列50_1~50_n之負極端分別透過開關SW1~SWn與電流驅動單元250耦接，且透過驅動電流I₁~I_n驅動發光二極體串列50_1~50_n發光。 The voltage converter 210 receives the power supply voltage V _DD and generates an operating voltage V _{CC that is} different from the power supply voltage V _DD according to the adjustment signal output by the conversion loop controller 220. The conversion loop controller 220 generates an adjustment signal based on the voltage it receives. The positive input terminal of the amplifier 230 receives the reference voltage V _R , and its negative input terminal receives the voltage output by the voltage selector 240, and accordingly outputs a voltage to the conversion loop controller 220, wherein the reference voltage V _R can be a fixed value. The voltage selector 240 is configured to select a voltage for outputting one of the negative terminals of the LED arrays 50_1~50_n. The positive terminal of the LED series 50_1~50_n receives the operating voltage V _CC , and the negative terminals of the LED series 50_1~50_n are coupled to the current driving unit 250 through the switches SW1 SWSW respectively, and the driving current I _{1 is} transmitted. ~I _n driving light-emitting diode series 50_1~50_n light.

當調光信號Sdim的責任週期為100%時，代表驅動裝置 200不會進行調光。此時，電流控制單元270會依據調光模式信號Smod產生控制信號Sco1控制開關SW1~SWn於一週期中同時導通，並透過控制電壓Vco1調整控制驅動電流I₁~I_n的大小D為電流上限值。當調光信號Sdim的責任週期不為100%時，代表驅動裝置200會進行調光。此時，電流控制單元270同樣依據調光模式信號Smod產生的控制信號Sco1以控制開關SW1~SWn於一週期中的導通時間為相等或均等，並透過控制電壓Vco1控制電流驅動單元250調整驅動電流I₁~I_n的大小，其中電流驅動單元250可以由多個壓控電流源所組成，以同時依據控制電壓Vco1調整驅動電流I₁~I_n的大小。值得一提的是，調光信號Sdim的責任週期與驅動裝置200是否進行調光的關係為用以說明，並可視實際需求而變動。 When the duty cycle of the dimming signal Sdim is 100%, it means that the driving device 200 does not perform dimming. At this time, the current control unit 270 generates the control signal Sco1 according to the dimming mode signal Smod to control the switches SW1 SWSWn to be simultaneously turned on in one cycle, and adjusts the magnitude D of the control driving current I ₁ ~I _n to be current through the control voltage Vco1. Limit. When the duty cycle of the dimming signal Sdim is not 100%, the representative driving device 200 performs dimming. At this time, the current control unit 270 also controls the conduction time of the switches SW1 SWSW in one cycle to be equal or equal according to the control signal Sco1 generated by the dimming mode signal Smod, and controls the current driving unit 250 to adjust the driving current through the control voltage Vco1. The size of I ₁ ~I _n , wherein the current driving unit 250 can be composed of a plurality of voltage controlled current sources to simultaneously adjust the magnitudes of the driving currents I ₁ ~I _n according to the control voltage Vco1. It is worth mentioning that the relationship between the duty cycle of the dimming signal Sdim and whether the driving device 200 performs dimming is for explanation and can be changed according to actual needs.

進一步來說明驅動裝置200進行調光的動作，圖2B為圖2A的發光二極體串列的電流波形示意圖。請參照圖2A及圖2B，當驅動裝置200進行調光且調光信號Sdim的責任週期大於等於預設值時，電流控制單元270依據調光模式信號Smod及調光信號Sdim產生多個控制信號Sco1及控制電壓Vco1。這些控制信號Sco1會控制開關SW1~SWn於週期T中同時保持導通，以同時提供驅動電流I₁~I_n至發光二極體串列50_1~50_n。發光二極體串列50_1~50_n上的電流會因為開關SW1~SWn保持導通而呈現直流狀而非脈衝狀。並且，電流驅動單元250依據控制電壓Vco1調整驅動電流I₁~I_n的電流大小D，其中電流大小D會與調光信號Sdim 的責任週期相關，例如責任週期為1/8，則電流大小D會等於電流上限值的1/8。而上述預設值可以為週期T除以驅動電流I₁~I_n的個數n，例如驅動電流的個數n為8，則預設值為週期的1/8(即T/8)。 Further, the operation of the driving device 200 to perform dimming will be described. FIG. 2B is a schematic diagram showing the current waveform of the LED array of FIG. 2A. Referring to FIG. 2A and FIG. 2B, when the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is greater than or equal to a preset value, the current control unit 270 generates a plurality of control signals according to the dimming mode signal Smod and the dimming signal Sdim. Sco1 and control voltage Vco1. These control signals Sco1 controls switches SW1 ~ SWn is turned on while maintaining period T, to simultaneously provide a driving current I ₁ ~ I _n to the light emitting diode tandem 50_1 ~ 50_n. The current on the LED series 50_1~50_n will be DC-like instead of pulsed because the switches SW1~SWn remain conductive. Moreover, the current driving unit 250 adjusts the current magnitude D of the driving currents I ₁ to I _n according to the control voltage Vco1, wherein the current magnitude D is related to the duty cycle of the dimming signal Sdim, for example, the duty cycle is 1/8, and the current magnitude D Will be equal to 1/8 of the upper current limit. The preset value may be the period T divided by the number n of the driving currents I ₁ ~I _n . For example, if the number n of driving currents is 8, the preset value is 1/8 of the period (ie, T/8).

圖2C為圖2A的發光二極體串列的另一電流波形示意圖。請參照圖2A及圖2C，當驅動裝置200進行調光且調光信號Sdim的責任週期小於預設值時，電流控制單元270同樣依據調光模式信號Smod及調光信號Sdim產生多個控制信號Sco1及控制電壓Vco1。這些控制信號Sco1會控制開關SW1~SWn於週期T中的導通時間t₂為均等，以分別輸出驅動電流I₁~I_n至發光二極體串列50_1~50_n，例如開關的數量為8，則導通時間t₂為1/8週期。電流驅動單元250依據控制電壓Vco1調整驅動電流I₁~I_n的電流大小D，其中電流大小D會與調光信號Sdim的責任週期及預設值相關，例如責任週期為1/16，則電流大小D會等於電流上限值的1/2，亦即責任週期(即1/16)除以預設值(即1/8)再乘以電流上限值。而驅動電流I₁~I_n的輸出順序可以依序或隨機順序。 2C is a schematic diagram of another current waveform of the LED array of FIG. 2A. Referring to FIG. 2A and FIG. 2C, when the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is less than a preset value, the current control unit 270 also generates a plurality of control signals according to the dimming mode signal Smod and the dimming signal Sdim. Sco1 and control voltage Vco1. The control signal Sco1 controls the on-times t ₂ of the switches SW1 SW SWn in the period T to be equal to output the driving currents I ₁ ~I _n to the LED series 50_1~50_n, for example, the number of switches is 8. Then, the on-time t ₂ is 1/8 cycle. The current driving unit 250 adjusts the current magnitude D of the driving current I ₁ ~I _n according to the control voltage Vco1, wherein the current magnitude D is related to the duty cycle and the preset value of the dimming signal Sdim, for example, the duty cycle is 1/16, then the current The size D will be equal to 1/2 of the upper current limit, that is, the duty cycle (ie 1/16) divided by the preset value (ie 1/8) and multiplied by the current upper limit. The output order of the drive currents I ₁ ~I _n may be in sequential or random order.

藉此，不論開關SW1~SWn依據調光信號Sdim的責任週期於週期T中同時導通或分別導通，其驅動電流I₁~I_n的電流總和大致上會保持於一定值，大幅降低操作電壓V_CC的抽載變化，甚或除消，以抑制因此產生的音頻雜訊及電磁干擾。 Therefore, regardless of whether the switches SW1 SWSWn are simultaneously turned on or respectively turned on in the period T according to the duty cycle of the dimming signal Sdim, the sum of the currents of the driving currents I ₁ to I _n is substantially maintained at a certain value, and the operating voltage V is greatly reduced. The pumping variation of _CC is even eliminated, to suppress the resulting audio noise and electromagnetic interference.

圖2D為圖2A的驅動裝置與發光二極體串列的波形示意圖。請參照圖2A及圖2D，在本實施例中，假設驅動裝置200只驅動發光二極體串列50_1及50_2，並且所接收到的調光信號Sdim的責任週期為1/4。此時，開關SW1及SW2受控於所接收到的控制信號Sco1分別導通且導通時間分別為T/2。並且，電流驅動單元250受控於控制電壓Vco1調整驅動電流I₁~I₂的電流大小D為電流上限值H的一半(即1/2)，其中電流上限值H可對應至電壓信號的高準位V。藉此，驅動裝置200可實現1/4的調光效果，且電流大小D會大致維持於電流上限值H的1/2，以抑制因此產生的音頻雜訊及電磁干擾。 2D is a schematic diagram of a waveform of the driving device and the LED array of FIG. 2A. Referring to FIG. 2A and FIG. 2D, in the present embodiment, it is assumed that the driving device 200 drives only the LED arrays 50_1 and 50_2, and the duty cycle of the received dimming signal Sdim is 1/4. At this time, the switches SW1 and SW2 are controlled to be respectively turned on by the received control signal Sco1 and the on-time is T/2, respectively. Moreover, the current driving unit 250 is controlled by the control voltage Vco1 to adjust the current magnitude D of the driving currents I ₁ to I ₂ to be half (ie 1/2) of the current upper limit value H, wherein the current upper limit value H can correspond to the voltage signal High level V. Thereby, the driving device 200 can achieve a 1/4 dimming effect, and the current magnitude D is substantially maintained at 1/2 of the current upper limit value H to suppress the audio noise and electromagnetic interference thus generated.

圖2E為圖2A的電流控制單元耦接調光偵測器的電路示意圖。請參照圖2E，在本實施例中，電流控制單元270包括多工器271、分散延遲產生器272及責任週期轉電壓轉換器273。當驅動裝置200進行調光且調光信號Sdim的責任週期大於等於預設值時，調光偵測器260的調光模式信號Smod會控制多工器271將其輸入端所接收的調光信號Sdim由其第一輸出端輸出至責任週期轉電壓轉換器273，以依據調光信號Sdim的責任週期調整控制電壓Vco1的大小。電流驅動單元250則依據控制電壓Vco1的大小同步調整驅動電流I₁~I_n的電流大小。同時，由於分散延遲產生器272未接收到調光信號Sdim，所以分散延遲產生器272的控制信號Sco1會控制開關SW1~SWn同時導通，以讓驅動電流I₁~I_n同時輸出至發光二極體串列50_1~50_n。 2E is a circuit diagram of the current control unit of FIG. 2A coupled to the dimming detector. Referring to FIG. 2E, in the present embodiment, the current control unit 270 includes a multiplexer 271, a dispersion delay generator 272, and a duty cycle to voltage converter 273. When the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is greater than or equal to a preset value, the dimming mode signal Smod of the dimming detector 260 controls the dimming signal received by the multiplexer 271 at its input end. The Sdim is output from its first output terminal to the duty cycle to voltage converter 273 to adjust the magnitude of the control voltage Vco1 according to the duty cycle of the dimming signal Sdim. The current driving unit 250 synchronously adjusts the magnitudes of the currents of the driving currents I ₁ to I _n according to the magnitude of the control voltage Vco1. Meanwhile, since the dispersion delay generator 272 does not receive the dimming signal Sdim, the control signal Sco1 of the dispersion delay generator 272 controls the switches SW1 to SWn to be simultaneously turned on, so that the driving currents I ₁ to I _{n are} simultaneously outputted to the light emitting diodes. The body string is 50_1~50_n.

當驅動裝置200進行調光且調光信號Sdim的責任週期小於預設值時，調光偵測器260的調光模式信號Smod會控制多工器 271將其輸入端所接收的調光信號Sdim由其第二輸出端輸出至分散延遲產生器272。分散延遲產生器272在接收到調光信號Sdim後，其產生的控制信號Sco1會控制開關SW1~SWn在一週期中會分別導通，並且開關SW1~SWn的導通時間會相同。一般而言，這些控制信號Sco1可以在不同時候傳送脈衝以使開關SW1~SWn於不同時候導通。而開關SW1~SWn的導通時間會分開但是相互接續，亦即導通開關的脈衝會在這些控制信號Sco1對應的端點被接續輸出，而此接續輸出的效果如同將脈衝進行位移一般。其中，脈衝位移的功能可以透過位移暫存器來完成，亦即這些控制信號Sco1在不同時候傳送脈衝的功能可以透過多個位移暫存器對脈衝進行位移並輸出來完成。 When the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is less than a preset value, the dimming mode signal Smod of the dimming detector 260 controls the multiplexer. 271 outputs the dimming signal Sdim received at its input terminal to its dispersion delay generator 272 from its second output terminal. After receiving the dimming signal Sdim, the dispersion delay generator 272 generates a control signal Sco1 that controls the switches SW1 SWSWn to be respectively turned on in one cycle, and the on-times of the switches SW1 SW SWn are the same. In general, these control signals Sco1 can transmit pulses at different times to cause the switches SW1~SWn to be turned on at different times. The on-times of the switches SW1~SWn are separated but connected to each other, that is, the pulses of the on-switch are successively outputted at the end points corresponding to the control signals Sco1, and the effect of the successive outputs is like the displacement of the pulses. The function of the pulse displacement can be completed by the displacement register, that is, the function of transmitting the pulse of the control signal Sco1 at different times can be performed by shifting and outputting the pulse through a plurality of displacement registers.

同時，分散延遲產生器272會將所接收到調光信號Sdim傳送到責任週期轉電壓轉換器273，並同時輸出一增益信號GN到到責任週期轉電壓轉換器273。責任週期轉電壓轉換器273依據調光信號Sdim的責任週期及增益信號GN調整控制電壓Vco1的大小，以同步調整驅動電流I₁~I_n的電流大小。其中，增益信號GN可以傳送增益數，增益信號GN所傳送增益數可以為驅動電流I₁~I_n的電流數，驅動電流I₁~I_n的電流數以8為例，則增益信號GN所傳送增益數為8。舉例來說，當調光信號Sdim的責任週期為1/16時，驅動電流I₁~I_n的電流大小應該為電流上限值的1/16，但再依據增益信號GN調整後，驅動電流I₁~I_n的電流大小被調整為電流上限值的1/2，再配合驅動電流I₁~I_n的輸出時間為週期的1/8，可達到1/16的調光效果。 At the same time, the dispersion delay generator 272 transmits the received dimming signal Sdim to the duty cycle to voltage converter 273 and simultaneously outputs a gain signal GN to the duty cycle to voltage converter 273. The duty cycle to voltage converter 273 adjusts the magnitude of the control voltage Vco1 according to the duty cycle of the dimming signal Sdim and the gain signal GN to synchronously adjust the magnitude of the current of the driving currents I ₁ to I _n . The gain signal GN can transmit the gain number, the gain number transmitted by the gain signal GN can be the number of currents of the driving current I ₁ ~I _n , and the current of the driving current I ₁ ~I _n is 8 , the gain signal GN The number of transmit gains is 8. For example, when the duty cycle of the dimming signal Sdim is 1/16, the current of the driving current I ₁ ~I _n should be 1/16 of the current upper limit value, but after the gain signal GN is adjusted, the driving current is The current of I ₁ ~I _n is adjusted to 1/2 of the current upper limit value, and the output time of the driving current I ₁ ~I _n is 1/8 of the period, which can achieve a dimming effect of 1/16.

值得一提的是，分散延遲產生器272在未接收到調光信號Sdim時，其可以輸出增益數為1的增益信號GN或不輸出增益信號GN。此外，責任週期轉電壓轉換器273在未接收到增益信號GN時，則依據調光信號Sdim的責任週期產生對應的控制電壓Vco1。 It is worth mentioning that the dispersion delay generator 272 can output the gain signal GN having a gain number of 1 or not the gain signal GN when the dimming signal Sdim is not received. In addition, when the duty cycle converter 273 does not receive the gain signal GN, the corresponding control voltage Vco1 is generated according to the duty cycle of the dimming signal Sdim.

圖2F為圖2E的責任週期轉電壓轉換器的電路示意圖。請參照圖2F，在本實施例中，責任週期轉電壓轉換器273包括低通濾波電路LPF1及類比乘法器ML1，其中低通濾波電路LPF1可以由電阻R1及電容C1所組成，但不以此限制其他實施例。低通濾波電路LPF1會將所接收的調光信號Sdim轉換為一直流準位，亦即低通濾波電路LPF1會依據調光信號Sdim的責任週期的不同輸出不同的直流準位。類比乘法器ML1會依據增益信號GN放大低通濾波電路LPF1輸出的直流準位作為控制電壓Vco1。當增益信號GN所傳送的增益數為1時，則控制電壓Vco1的準位會相同於低通濾波電路LPF1輸出的直流準位。當增益信號GN所傳送的增益數為2時，則控制電壓Vco1的準位會2倍於低通濾波電路LPF1輸出的直流準位，其餘則以此類推。 2F is a circuit diagram of the duty cycle to voltage converter of FIG. 2E. Referring to FIG. 2F, in the embodiment, the duty cycle to voltage converter 273 includes a low pass filter circuit LPF1 and an analog multiplier ML1, wherein the low pass filter circuit LPF1 can be composed of a resistor R1 and a capacitor C1, but not Other embodiments are limited. The low-pass filter circuit LPF1 converts the received dimming signal Sdim into a constant current level, that is, the low-pass filter circuit LPF1 outputs different DC levels according to the duty cycle of the dimming signal Sdim. The analog multiplier ML1 amplifies the DC level output of the low-pass filter circuit LPF1 as the control voltage Vco1 according to the gain signal GN. When the gain number transmitted by the gain signal GN is 1, the level of the control voltage Vco1 is the same as the DC level output by the low-pass filter circuit LPF1. When the gain number transmitted by the gain signal GN is 2, the level of the control voltage Vco1 is twice the DC level output by the low-pass filter circuit LPF1, and the rest is deduced by analogy.

圖2G為圖2E的責任週期轉電壓轉換器的另一電路示意圖。請參照圖2F及圖2G，其不同之處在於多工器mux1。多工器mux1會依據調光模式信號Smod決定低通濾波電路LPF1輸出的直流準位為傳送到類比乘法器ML1或直接輸出。換言之，當驅動裝置200進行調光且調光信號Sdim的責任週期大於等於預設值時，會直接輸出低通濾波電路LPF1所輸出的直流準位作為控制電壓Vco1。當驅動裝置200進行調光且調光信號Sdim的責任週期小於預設值時，低通濾波電路LPF1輸出的直流準位為傳送到類比乘法器ML1，以依據增益信號GN放大後輸出作為控制電壓Vco1。 2G is another circuit diagram of the duty cycle to voltage converter of FIG. 2E. Please refer to FIG. 2F and FIG. 2G, which differ in the multiplexer mux1. The multiplexer mux1 determines the DC level output of the low-pass filter circuit LPF1 to be transmitted to the analog multiplier ML1 or the direct output according to the dimming mode signal Smod. In other words, when driving When the device 200 performs dimming and the duty cycle of the dimming signal Sdim is greater than or equal to a preset value, the DC level outputted by the low-pass filter circuit LPF1 is directly output as the control voltage Vco1. When the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is less than a preset value, the DC level outputted by the low-pass filter circuit LPF1 is transmitted to the analog multiplier ML1 to be amplified according to the gain signal GN and output as a control voltage. Vco1.

圖2H為圖2A的電流控制單元耦接調光偵測器的另一電路示意圖。請參照圖2E、圖2H，其不同之處在於分散延遲產生器274，以及省卻多工器271。當驅動裝置200進行調光且調光信號Sdim的責任週期大於等於預設值時，分散延遲產生器274會依據調光模式信號Smod的控制信號Sco1會控制開關SW1~SWn同時導通，並且不會輸出增益信號GN或輸出增益數為1的增益信號GN。在分散延遲產生器274不輸出增益信號GN的情況下，責任週期轉電壓轉換器273會依據所接收到的調光信號Sdim產生控制電壓Vco1。在分散延遲產生器274輸出增益數為1的增益信號GN的情況下，責任週期轉電壓轉換器273會依據所接收到的調光信號Sdim及增益信號GN產生控制電壓Vco1。 2H is another circuit diagram of the current control unit of FIG. 2A coupled to the dimming detector. Please refer to FIG. 2E and FIG. 2H, which differ in the dispersion delay generator 274, and the multiplexer 271 is omitted. When the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is greater than or equal to a preset value, the dispersion delay generator 274 controls the switches SW1 SWSWn to be simultaneously turned on according to the control signal Sco1 of the dimming mode signal Smod, and does not The gain signal GN or the gain signal GN whose output gain number is one is output. In the case where the dispersion delay generator 274 does not output the gain signal GN, the duty cycle-to-voltage converter 273 generates the control voltage Vco1 in accordance with the received dimming signal Sdim. In the case where the dispersion delay generator 274 outputs the gain signal GN having the gain number of 1, the duty cycle-to-voltage converter 273 generates the control voltage Vco1 in accordance with the received dimming signal Sdim and the gain signal GN.

當驅動裝置200進行調光且調光信號Sdim的責任週期小於預設值時，分散延遲產生器274會依據調光模式信號Smod產生對應的控制信號Sco1以控制開關SW1~SWn在一週期中會分別導通，並且輸出對應驅動電流I₁~I_n的電流數的增益信號GN。責任週期轉電壓轉換器273會依據所接收到的調光信號Sdim及增益信號GN產生控制電壓Vco1。 When the driving device 200 performs dimming and the duty cycle of the dimming signal Sdim is less than a preset value, the dispersion delay generator 274 generates a corresponding control signal Sco1 according to the dimming mode signal Smod to control the switches SW1 SWSWn to be in a cycle. They are respectively turned on, and a gain signal GN corresponding to the _number of currents of the driving currents I ₁ to I _n is output. The duty cycle to voltage converter 273 generates a control voltage Vco1 based on the received dimming signal Sdim and the gain signal GN.

圖2I為圖2A的電流控制單元耦接調光偵測器的再一電路示意圖。請參照圖2I，本實施例的驅動電流I₁~I_n的電流數以8個為例，亦即預設值為1/8。調光偵測器260包括低通濾波電路LPF2、類比數位轉換器261(analog-to-digital converter,ADC)與或閘262，其中類比數位轉換器261以4位元的轉換器為例。若調光信號Sdim的責任週期為1/4時，則類比數位轉換器261會輸出”0100”，以數位型態顯示就是”0100 0000”。預設值以數位型態顯示就是”0010 0000”。 2I is a schematic diagram of still another circuit of the current control unit of FIG. 2A coupled to the dimming detector. Referring to FIG. 2I, the number of currents of the driving currents I ₁ to I _n in this embodiment is eight, that is, the preset value is 1/8. The dimming detector 260 includes a low pass filter circuit LPF2, an analog-to-digital converter (ADC) and an OR gate 262, wherein the analog bit converter 261 is exemplified by a 4-bit converter. If the duty cycle of the dimming signal Sdim is 1/4, the analog digital converter 261 outputs "0100", and the digital display is "0100 0000". The preset value is displayed as a digit type "0010 0000".

依據上述，在此只要前三個最高位元出現”1”即大於於預設值，因此可以將前三個最高位元以或運算產生調光模式信號Smod。而類比數位轉換器261輸出的”0100 0000”經或閘262對前三個最高位元運算後，會產生高邏輯準位的調光模式信號Smod，代表調光信號Sdim的責任週期大於預設值。接著，多工器271依據調光模式信號Smod將類比數位轉換器261輸出的”0100 0000”輸出至責任週期轉電壓轉換器276，以將數位型態的”0100 0000”轉換為類比型態輸出以作為控制電壓Vco1，其中責任週期轉電壓轉換器276可以包括數位類比轉換器(digital-to-analog converter,DAC)以將數位型態”0100 0000”轉換為類比型態。並且，分散延遲產生器275在未接收到類比數位轉換器261的輸出時，則對應產生多個控制信號Sco1以控制開關SW1~SWn同時導通。 According to the above, as long as the first three highest bits appear "1", which is greater than the preset value, the first three highest bits can be ORed to generate the dimming mode signal Smod. The "0100 0000" output from the analog-to-digital converter 261 is operated by the OR gate 262 to the first three highest bits, and a dimming mode signal Smod having a high logic level is generated, and the duty cycle of the dimming signal Sdim is greater than the preset. value. Next, the multiplexer 271 outputs "0100 0000" output from the analog-to-digital converter 261 to the duty cycle-to-voltage converter 276 according to the dimming mode signal Smod to convert the digital type "0100 0000" into an analog type output. As the control voltage Vco1, the duty cycle to voltage converter 276 may include a digital-to-analog converter (DAC) to convert the digital type "0100 0000" into an analog type. Further, when the output of the analog-to-digital converter 261 is not received, the dispersion delay generator 275 generates a plurality of control signals Sco1 to control the switches SW1 to SWn to be simultaneously turned on.

若調光信號Sdim的責任週期為1/16時，類比數位轉換器261會輸出”0001 0000”，而或閘262對前三個最高位元進行運算後，會產生低邏輯準位的調光模式信號Smod。接著，多工器271依據調光模式信號Smod將類比數位轉換器261輸出的”0001 0000”輸出至責任週期轉電壓轉換器276。此時，分散延遲產生器275則對應產生多個控制信號Sco1以控制開關SW1~SWn在一週期中會分別導通。並且，分散延遲產生器275依據預設值調整類比數位轉換器261輸出的”0001 0000”，亦即將”0001 0000”乘以8(等同左移三個位元)而變成”1000 0000”。將此”1000 0000”輸出作為增益信號，則責任週期轉電壓轉換器276將”1000 0000”轉換為類比型態輸出作為控制電壓Vco1。值得注意的是，在本實施例中，責任週期轉電壓轉換器276可不接收調光信號Sdim，以簡化電路設計的困難度。 If the duty cycle of the dimming signal Sdim is 1/16, the analog digital conversion The 261 will output "0001 0000", and the OR gate 262 will operate on the first three highest bits to generate a low logic level dimming mode signal Smod. Next, the multiplexer 271 outputs "0001 0000" output from the analog-to-digital converter 261 to the duty cycle-to-voltage converter 276 in accordance with the dimming mode signal Smod. At this time, the dispersion delay generator 275 correspondingly generates a plurality of control signals Sco1 to control the switches SW1 SWSWn to be respectively turned on in one cycle. Further, the dispersion delay generator 275 adjusts "0001 0000" output from the analog-to-digital converter 261 in accordance with the preset value, that is, "0001 0000" is multiplied by 8 (equivalently shifted to the left by three bits) to become "1000 0000". Taking this "1000 0000" output as a gain signal, the duty cycle to voltage converter 276 converts "1000 0000" into an analog type output as the control voltage Vco1. It should be noted that in the present embodiment, the duty cycle to voltage converter 276 may not receive the dimming signal Sdim to simplify the circuit design.

依照上述說明，可以將上述動作彙整為方法以應用於驅動裝置200。圖3A為根據本發明一實施例的驅動方法的流程圖。請參照圖2A及圖3A，驅動裝置200會接收調光信號Sdim，依據調光信號Sdim可偵測驅動裝置200是否在進行調光(步驟S301)。當驅動裝置200在進行調光時，則均勻分配驅動電流I₁~I_n在一週期中的輸出時間(步驟S302)，並且驅動裝置200會輸出驅動電流I₁~I_n以分別驅動發光二極體串列50_1~50_n。當驅動裝置200不在進行調光時，則結束此驅動方法。 According to the above description, the above actions can be summarized into a method for application to the drive device 200. 3A is a flow chart of a driving method in accordance with an embodiment of the present invention. Referring to FIG. 2A and FIG. 3A, the driving device 200 receives the dimming signal Sdim, and according to the dimming signal Sdim, it can detect whether the driving device 200 is performing dimming (step S301). When the driving device 200 performs dimming, the output time of the driving currents I ₁ to I _n in one cycle is evenly distributed (step S302), and the driving device 200 outputs the driving currents I ₁ to I _n to respectively drive the two lights. The polar body series is 50_1~50_n. When the driving device 200 is not performing dimming, the driving method is ended.

圖3B為根據本發明另一實施例的驅動方法的流程圖。請參照圖3A及圖3B，其不同之處在於步驟S311、S312及S313。當驅動裝置在進行調光時，則判斷調光信號的責任週期是否小於預設值(步驟S311)。當調光信號的責任週期不小於預設值時，則於一週期中同時輸出驅動電流，並依據調光信號調整驅動電流的電流大小(步驟S312)。當調光信號的責任週期小於預設值時，則均勻分配驅動電流在一週期中的輸出時間，並對應地調整驅動電流的電流大小(步驟S313)。其中，步驟S312及S313可參照上述實施例的說明，在此則不加以贅述。 FIG. 3B is a flow chart of a driving method according to another embodiment of the present invention. Please refer to FIG. 3A and FIG. 3B, which differ in steps S311, S312 and S313. When the driving device is performing dimming, it is judged whether the duty cycle of the dimming signal is less than a preset value (step S311). When the duty cycle of the dimming signal is not less than the preset value, the driving current is simultaneously outputted in one cycle, and the current magnitude of the driving current is adjusted according to the dimming signal (step S312). When the duty cycle of the dimming signal is less than the preset value, the output time of the driving current in one cycle is evenly distributed, and the current magnitude of the driving current is correspondingly adjusted (step S313). For the steps S312 and S313, reference may be made to the description of the above embodiments, and details are not described herein.

綜上所述，本發明諸實施例的發光二極體的驅動裝置及其驅動方法，當驅動裝置進行調光且調光信號的責任週期小於預設值時，則均勻分配各驅動電流於一週期中的輸出時間，並對應地調整各驅動電流的電流大小。當驅動裝置進行調光且調光信號的責任週期大於或等於預設值時，於週期中同時輸出驅動電流，並依據調光信號調整驅動電流的大小。藉此，可抑制驅動電流的總和變動過大所造成的音頻雜訊及電磁干擾。 In summary, the driving device for driving the LED of the embodiments of the present invention and the driving method thereof, when the driving device performs dimming and the duty cycle of the dimming signal is less than a preset value, uniformly distributes the driving currents to one The output time in the cycle, and adjust the current of each drive current correspondingly. When the driving device performs dimming and the duty cycle of the dimming signal is greater than or equal to the preset value, the driving current is simultaneously outputted in the cycle, and the driving current is adjusted according to the dimming signal. Thereby, it is possible to suppress audio noise and electromagnetic interference caused by excessive variation of the drive current.

雖然本發明已以實施例揭露如上，然其並非用以限定本發明，任何所屬技術領域中具有通常知識者，在不脫離本發明的精神和範圍內，當可作些許的更動與潤飾，故本發明的保護範圍當視後附的申請專利範圍所界定者為準。 Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

50_1~50_n‧‧‧發光二極體串列 50_1~50_n‧‧‧Light diode series

200‧‧‧驅動裝置 200‧‧‧ drive

210‧‧‧電壓轉換器 210‧‧‧Voltage Converter

220‧‧‧轉換迴路控制器 220‧‧‧Switching loop controller

230‧‧‧放大器 230‧‧ ‧Amplifier

240‧‧‧電壓選擇器 240‧‧‧Voltage selector

250‧‧‧電流驅動單元 250‧‧‧current drive unit

260‧‧‧調光偵測器 260‧‧‧ dimming detector

270‧‧‧電流控制單元 270‧‧‧ Current Control Unit

SW1~SWn‧‧‧開關 SW1~SWn‧‧‧ switch

Scol‧‧‧控制信號 Scol‧‧‧ control signal

Smod‧‧‧調光模式信號 Smod‧‧‧ dimming mode signal

Sdim‧‧‧調光信號 Sdim‧‧‧ dimming signal

I₁~I_n‧‧‧電流 I ₁ ~I _n ‧‧‧ Current

V_DD、V_CC、V_R‧‧‧電壓 V _DD , V _CC , V _R ‧‧‧ voltage

Vcol‧‧‧控制電壓 Vcol‧‧‧ control voltage

Claims

一種發光二極體的驅動方法，適用於一驅動裝置，該驅動方法包括：接收一調光信號；偵測該驅動裝置是否進行調光；若該驅動裝置被偵測到進行調光，判斷用於調光控制的一既定要求是否滿足，其中該既定要求包括該調光信號的一責任週期是否小於一預設值；當用於調光控制的該既定要求未滿足時，調整多個驅動電流個別的電流大小，並且在一週期的全部時間中輸出各該些驅動電流；以及當用於調光控制的該既定要求被滿足時，分別在一週期的部分時間中輸出各該些驅動電流。 A driving method for a light emitting diode is applicable to a driving device, the driving method includes: receiving a dimming signal; detecting whether the driving device performs dimming; and if the driving device is detected to perform dimming, determining Whether a predetermined requirement of the dimming control is satisfied, wherein the predetermined requirement includes whether a duty cycle of the dimming signal is less than a predetermined value; and when the predetermined requirement for dimming control is not satisfied, adjusting a plurality of driving currents The respective current magnitudes are outputted, and each of the drive currents is outputted during a period of time; and when the predetermined requirements for dimming control are satisfied, the drive currents are respectively output during a portion of a cycle.

如申請專利範圍第1項所述的發光二極體的驅動方法，更包括：在用於調光控制的該既定要求未被滿足的情況中，依據一調光信號調整該些驅動電流個別的電流大小。 The driving method of the light emitting diode according to claim 1, further comprising: adjusting the driving currents according to a dimming signal in a case where the predetermined requirement for dimming control is not satisfied Current size.

如申請專利範圍第2項所述的發光二極體的驅動方法，其中在用於調光控制的該既定要求未被滿足的情況中，依據該調光信號的一責任週期調整該些驅動電流個別的電流大小。 The driving method of the light emitting diode according to claim 2, wherein in the case where the predetermined requirement for dimming control is not satisfied, the driving currents are adjusted according to a duty cycle of the dimming signal Individual current sizes.

如申請專利範圍第1項所述的發光二極體的驅動方法，更包括：在用於調光控制的該既定要求被滿足的情況中，依據一調光信號配置該些驅動電流個別的電流大小及於一週期中個別的輸出時間。 The method for driving a light-emitting diode according to claim 1, further comprising: In the case where the predetermined requirement for dimming control is satisfied, the magnitudes of the individual currents of the driving currents and the individual output times in a cycle are configured according to a dimming signal.

如申請專利範圍第4項所述的發光二極體的驅動方法，其中在用於調光控制的該既定要求被滿足的情況中，依據該調光信號的一責任週期決定該些驅動電流個別的電流大小及於該週期中個別的輸出時間。 The driving method of the light emitting diode according to claim 4, wherein in the case where the predetermined requirement for dimming control is satisfied, the driving currents are individually determined according to a duty cycle of the dimming signal. The current magnitude and the individual output times in the cycle.

如申請專利範圍第1項所述的發光二極體的驅動方法，更包括：不論各該些驅動電流是否在一週期的部分時間或全部時間中輸出，在該調光信號為相同責任週期時，該些驅動電流於一週期中的總和實質上為一固定值。 The method for driving a light-emitting diode according to claim 1, further comprising: whether the respective driving currents are output in part or all of a period of time, when the dimming signal is in the same duty cycle The sum of the drive currents in one cycle is substantially a fixed value.

一種發光二極體的驅動方法，適用於一驅動裝置，該驅動方法包括：接收一調光信號；偵測該驅動裝置是否進行調光；以及若該驅動裝置被偵測到進行調光，依據該調光信號的一責任週期調整多個驅動電流中個別的電流大小及輸出時間的至少其一，以使該些驅動電流於一週期中的總和實質上正比於該調光信號的該責任週期。 A driving method for a light emitting diode is applicable to a driving device, the driving method includes: receiving a dimming signal; detecting whether the driving device performs dimming; and if the driving device is detected to perform dimming, according to A duty cycle of the dimming signal adjusts at least one of an individual current magnitude and an output time of the plurality of driving currents such that a sum of the driving currents in a cycle is substantially proportional to the duty cycle of the dimming signal .

如申請專利範圍第7項所述的發光二極體的驅動方法，其中在至少一個調整方式中，僅依據該調光信號的該責任週期調整各該些驅動電流個別的電流大小；以及在至少一個另外的調整方式中，依據該調光信號的該責任週期同時調整各該些驅動電流個別的電流大小及在該週期的輸出時間。 The method for driving a light-emitting diode according to claim 7, wherein In at least one adjustment mode, the current magnitudes of the respective driving currents are adjusted according to only the duty cycle of the dimming signal; and in at least one other adjustment mode, the duty cycle is adjusted according to the duty cycle of the dimming signal The magnitude of the individual currents of the drive currents and the output time during the cycle.

如申請專利範圍第7項所述的發光二極體的驅動方法，其中在至少一個調整方式中，於該週期的全部時間輸出各該些驅動電流；以及在至少一個另外的調整方式中，於該週期的部分時間分別輸出各該些驅動電流。 The method for driving a light-emitting diode according to claim 7, wherein in at least one adjustment mode, each of the driving currents is outputted at all times of the cycle; and in at least one other adjustment mode, Part of the period of the cycle outputs the respective drive currents.

如申請專利範圍第9項所述的發光二極體的驅動方法，其中各該些驅動電流輸出於該週期的部分時間或全部時間為依據該調光信號的責任週期是否小於一預定值來決定。 The method for driving a light-emitting diode according to claim 9, wherein a part or all of the time during which the driving currents are outputted in the period is determined according to whether a duty cycle of the dimming signal is less than a predetermined value. .

如申請專利範圍第9項所述的發光二極體的驅動方法，其中，在該調光信號為相同責任週期所對應的調整方式中，不論各該些驅動電流是否在該週期的部分時間或全部時間中輸出，該些驅動電流於該週期中的總和實質上維持於一固定值。 The method for driving a light-emitting diode according to claim 9, wherein, in the adjustment mode corresponding to the same duty cycle of the dimming signal, whether or not each of the driving currents is at a part of the period or Outputs all of the time, and the sum of the drive currents in the period is substantially maintained at a fixed value.

一種用以驅動多個發光二極體的驅動電路，包括：多個開關，用以耦接該些發光二極體；一調光偵測器，用以接收一調光信號及依據該調光信號輸出一調光模式信號；以及一電流控制單元，用以依據該調光模式信號及該調光信號輸出多個控制信號，其中該些控制信號分別控制該些開關的導通狀態。 A driving circuit for driving a plurality of light emitting diodes, comprising: a plurality of switches for coupling the light emitting diodes; a light adjusting detector for receiving a light dimming signal and according to the dimming The signal outputs a dimming mode signal; a current control unit is configured to output a plurality of control signals according to the dimming mode signal and the dimming signal, wherein the control signals respectively control an on state of the switches.

如申請專利範圍第12項所述的驅動電路，更包括一電流驅動單元，耦接於該些開關及該電流控制單元之間，並且該電流控制單元更依據該調光模式信號及該調光信號輸出一控制電壓，其中該控制電壓控制該電流驅動單元調整多個驅動電流以驅動該些發光二極體。 The driving circuit of claim 12, further comprising a current driving unit coupled between the switches and the current control unit, and the current control unit is further configured according to the dimming mode signal and the dimming The signal outputs a control voltage, wherein the control voltage controls the current driving unit to adjust a plurality of driving currents to drive the light emitting diodes.

如申請專利範圍第12項所述的驅動電路，其中該調光偵測器依據該調光信號偵測調光是否進行，並且依據偵測結果輸出調光模式信號。 The driving circuit of claim 12, wherein the dimming detector detects whether the dimming is performed according to the dimming signal, and outputs a dimming mode signal according to the detection result.

如申請專利範圍第14項所述的驅動電路，其中該調光偵測器依據該調光信號的一責任週期偵測調光是否進行。 The driving circuit of claim 14, wherein the dimming detector detects whether dimming is performed according to a duty cycle of the dimming signal.

如申請專利範圍第14項所述的驅動電路，其中該調光偵測器更偵測該調光信號的一責任週期是否小於一預設值，並輸出該調光模式信號至該電流控制單元以配置該些開關的導通狀態。 The driving circuit of claim 14, wherein the dimming detector further detects whether a duty cycle of the dimming signal is less than a predetermined value, and outputs the dimming mode signal to the current control unit. To configure the conduction state of the switches.

如申請專利範圍第16項所述的驅動電路，其中該調光偵測器偵測該調光信號的該責任週期是否小於該預設值，以輸出該調光模式信號至該電流控制單元，以使該電流控制單元調整多個驅動電流以驅動該些發光二極體。 The driving circuit of claim 16, wherein the dimming detector detects whether the duty cycle of the dimming signal is less than the preset value, to output the dimming mode signal to the current control unit, The current control unit adjusts a plurality of driving currents to drive the light emitting diodes.

如申請專利範圍第16項所述的驅動電路，其中在該調光偵測器偵測到調光被進行且該調光信號的該責任週期小於該預設值的情況下，該電流控制單元輸出該些控制信號以控制該些開關於一週期的部分時間中為導通。 The driving circuit of claim 16, wherein the dimming detector detects that dimming is performed and the duty cycle of the dimming signal is less than the preset In the case of a value, the current control unit outputs the control signals to control the switches to be turned on during a portion of a cycle.

如申請專利範圍第16項所述的驅動電路，其中在該調光偵測器偵測到調光被進行且該調光信號的該責任週期未小於該預設值的情況下，該電流控制單元輸出該些控制信號以控制各該些開關於一週期的全部時間中為導通。 The driving circuit of claim 16, wherein the current control is performed when the dimming detector detects that dimming is performed and the duty cycle of the dimming signal is not less than the preset value. The unit outputs the control signals to control each of the switches to be turned on for the entire time of one cycle.

如申請專利範圍第17項所述的驅動電路，其中在該調光偵測器偵測到調光被進行且該調光信號的該責任週期小於該預設值的情況下，該電流控制單元輸出該些控制信號以控制各該些開關為於一週期的部分時間中分別導通。 The driving circuit of claim 17, wherein the current control unit is configured when the dimming detector detects that dimming is performed and the duty cycle of the dimming signal is less than the preset value. The control signals are output to control each of the switches to be respectively turned on during a portion of a cycle.

如申請專利範圍第17項所述的驅動電路，其中不論該調光信號的該責任週期是否小於該預設值，該些驅動電流為調整以使該些驅動電流於一週期中的總和實質上正比於該調光信號的該責任週期。 The driving circuit of claim 17, wherein the driving current is adjusted so that the sum of the driving currents in a cycle is substantially no matter whether the duty cycle of the dimming signal is less than the preset value. This duty cycle is proportional to the dimming signal.

一種電子裝置，包括：一如申請專利範圍第12項所述的驅動電路；以及多個發光二極體，耦接且驅動於該驅動電路。 An electronic device comprising: the driving circuit according to claim 12; and a plurality of light emitting diodes coupled to and driven by the driving circuit.

一種發光二極體的驅動方法，適用於一驅動裝置，該驅動方法包括：接收一調光信號；偵測該驅動裝置是否進行調光；若該驅動裝置進行調光，判斷該調光信號的一責任週期是否小於一預設值；當該調光信號的該責任週期未小於該預設值，依據該調光信號調整多個驅動電流個別的電流大小，並且於一週期的全部時間輸出各該些驅動電流；以及當該調光信號的該責任週期小於該預設值，各該些驅動電流分別於一週期的部分時間輸出。 A driving method for a light emitting diode is applicable to a driving device, the driving method includes: receiving a dimming signal; detecting whether the driving device performs dimming; and if the driving device performs dimming, determining the dimming signal Is a duty cycle When the duty cycle of the dimming signal is not less than the preset value, the current magnitudes of the plurality of driving currents are adjusted according to the dimming signal, and the driving currents are outputted at all times of a cycle. And when the duty cycle of the dimming signal is less than the preset value, each of the driving currents is outputted at a partial time of a cycle.

一種發光二極體的驅動裝置，包括：一電流驅動單元，輸出多個驅動電流以個別驅動多個發光二極體；多個開關，個別耦接於該電流驅動單元及該些發光二極體之間，用以控制該些驅動電流是否輸出至該些發光二極體；一調光偵測器，接收一調光信號，且依據該調光信號偵測該驅動裝置是否進行調光且偵測該調光信號的一責任週期是否小於一預設值，以輸出一調光模式信號；以及一電流控制單元，耦接該調光偵測器及該些開關，並且控制該些開關的導通時間，其中當該驅動裝置進行調光且該調光信號的該責任週期未小於該預設值時，該電流控制單元控制各該些開關為導通於一週期的全部時間，並且控制該電流驅動單元依據該調光信號調整該些驅動電流個別的電流大小；以及當該驅動裝置進行調光且該調光信號的該責任週期小於該預設值時，該電流控制單元控制各該些開關為導通於一週期的部份時間。 A driving device for a light emitting diode includes: a current driving unit that outputs a plurality of driving currents to individually drive a plurality of light emitting diodes; and a plurality of switches individually coupled to the current driving unit and the light emitting diodes Between the control of whether the driving current is output to the light emitting diodes; a dimming detector receives a dimming signal, and detects whether the driving device performs dimming and detecting according to the dimming signal Measuring whether a duty cycle of the dimming signal is less than a preset value to output a dimming mode signal; and a current control unit coupling the dimming detector and the switches, and controlling conduction of the switches Time, wherein when the driving device performs dimming and the duty cycle of the dimming signal is not less than the preset value, the current control unit controls each of the switches to be turned on for a full period of time, and controls the current driving The unit adjusts an individual current magnitude of the driving currents according to the dimming signal; and when the driving device performs dimming and the duty cycle of the dimming signal is less than the preset value, the current is Unit controls each of the switches is turned on in a part of the cycle time.