M408048 五、新型說明： 【新型所屬之技術領域】 本創作係關於一種燈條，特別是有關一種液晶顯示裝置之 燈條。 【先前技術】M408048 V. New description: [New technical field] This creation is about a light bar, especially a light bar for a liquid crystal display device. [Prior Art]
在薄膜電晶體液晶顯示裝置（thin film transistor liquid crystal display, TFT LCD)中，由於液晶本身不會發光，因此需 要由背光模組提供顯示影像所需的光線。由於現在的產品多以 輕薄短小為目標，因此越來越多液晶顯示裝置以發光二極體 (light emitting diode, LED)取代冷陰極管（cold cathode fluorescent lamp, CCFL)作為背光模組中的發光元件。通常有多 組發光二極體迴路製作於長條型的電路板上以形成燈條（light bar)，而用以驅動電路板上之發光二極體迴路的驅動電路係另 外製作於獨立之顯示裝置迴路板上，再利用軟性電路板 (flexible printed circuit, FPC)的多指型金手指端子及連接器 (connector)將電路板上之發光二極體迴路與顯示裝置迴路板上 之驅動電路電性連接，形成完整迴路。 習知驅動迴路具有下列缺點。首先，顯示裝置迴路板上之 驅動電路包括一多迴路式驅動積體電路（integrated circuit, 1C) 搭配一回授電阻來設定發光二極體迴路的定電流值，由於每條 發光二極體迴路的内阻有差異，會造成流過每條發光二極體迴 路的定電流值有誤差*使得液晶顯不裝置不同區塊顯不的免度 不同，影響顯示品質。 再者，電路板上之發光二極體迴路係彼此並聯，代表迴路 越多時，需要越多的軟性電路板及連接器來電性連接發光二極 3 M408048 體迴路及驅動電路，因此造成成本增加β 因此需要對上述習知發光二極體迴路及驅動電路分開設 置而導致的問題提出解決方法。 【新型内容】 本創作之一目的在於提供一種液晶顯示裝置之燈條，其能 減少驅動電路所需之元件及成本。 為達到上述目的’根據本創作之液晶顯示裝置之燈條包括 一電路板、至少一發光元件以及至少一定電流單元。該至少一 發光70件係設置於該電路板上。該至少一定電流單元係設置於 該電路板上，其用以驅動該至少一發光元件。 根據本創作之液晶顯示裝置之燈條將驅動發光元件之定 電流單元直接製作在電路板上，因此不需使用多迴路驅動積體 電路此外’也無需使用軟性電路板及連接胃電性連接多迴路 驅動積體電路及發光元件，比起習知技術更能減少成本。 【實施方式】 以下結合附圖對本創作的技術方案進行詳細說明。 請參閱第丨圖，係示意圖說明本創作第—實施例之液晶增 不裝置之燈條。該液晶顯示裝置之燈條包括—電路…〇、至小 一發光元件（圖中以發光元件2〇'22、24代表）以及至少一定^ ，單元（圖中以定電流單元3〇、32、34代表）。該等發光 22、24係設置於該電路板10上。各發光元件20、22、24分， 包括至少-發光二極體(圊中以5個發光二極體％串聯: 各定電流單元30、32、34係設置於該電珞板1〇上盆 流單元30用以提供㈣蚊電流來驅動發光元件加，、定電: M408048 早凡32用以提供穩定的定電流來驅動發光元件22，定電流單 .元34用以提供穩定的定電流來驅動發光元件24。由於定電流 單元30、32、34的結構與操作均相同，以下僅以定電流單元 ; 30當作例子說明。 於本實施例申，定電流單元30包括一雙載子接面電晶體 (bipolar junction transist〇r，BJT)T、一第一電阻 、一第二電 •阻R2以及-第三電⑯们。雙載子接面電晶體τ具有一：極 • (base)B、一集極（e〇llect〇r)C W 及-射極（emitter)E。第一電阻 # Ri之兩端分別電性連接至一電壓源¥1以及雙載子接面電晶體 I之基極B。第二電阻R2之兩端分別f性連接至雙載子接面電 晶體τ之射極E以及接地GND。第三電阻R3之兩端分別電性 連接至雙載子接面電晶體T之基極B以及接地遍。發光元 件係電性連接於電壓源¥1以及雙載子接面電晶體τ之集極 c之間。 電壓源VI為系統端所提供，其電愿至少需大於發光元件 • 20產生最大亮度時所需之電壓的總和，亦即需大於每一發光二 ·.知體26產生最大亮度時所需之電壓的總和，以本實施例而言， 至少需大於5個發光二極體26產生最大亮度時所需之電壓的 〜和。舉例來說，若一個發光二極體26產生最大亮度時所需 之電壓為3.5伏特（V)，則電壓源VI至少要提供3.5伏特*5 = 17 5 伏特的電壓’例如可提供19伏特。若設計基極b之電壓為3 6 伏特，基極B與射極E之順向導通電壓假設為0.6伏特，則射 椏E之電壓於雙載子接面電晶體τ導通時為3伏特，第二電阻 5 M408048 R2= 3伏特=15()歐姆（Ω)。接著，設計第一電阻尺丨之值及第 20*安培 三電阻R3之值，為使漏電流減少，流過第一電阻R1及第三電 阻R3之電流值應小於1毫安培（mA)，因此第一電阻R1之值及 第三電阻R3之值須選擇較高等級，由於基極B之電壓為3.6 伏特，假設第三電阻R3選擇100千歐姆（kD)，流過第三電阻 R3的電流=3石伏特=〇 〇36毫安培，代表流過第一電阻R1的 100千歐姆 電流也為0.036毫安培，因此第一電阻R1=(19伏特_3·6伏特）g428 0.036毫安培 千歐姆。 又，定電流單元32、34係分別提供定電流來驅動發光元 件22、24，其設計原理與定電流單元30相同，此不再贅述。 請參閱第2圖，係示意圖說明本創作第二實施例之液晶顯 示裝置之燈條之。該液晶顯示裝置之燈條包括一電路板10、至 少一發光元件（圖中以發光元件20、22、24代表）以及至少一定 電流單元（圖中以定電流單元40、42、44代表）。該等發光元件 20、22、24與係設置於該電路板10上。各發光元件20、22、 24分別包括至少一發光二極體26。各定電流單元40、42、44 係設置於該電路板10上，其中定電流單元40用以提供穩定的 定電流來驅動發光元件20，定電流單元42用以提供穩定的定 電流來驅動發光元件22，定電流單元44用以提供穩定的定電 流來驅動發光元件24。 M408048 第二實施例與第一實施例之不同在於第二實施例之定電 流單元40、42、44中係以一基納二極體（zener di〇de)z代替第 —實施例之定電流單元30、32、34中的第三電阻R3。以定電 流單元40為例，基納二極體z具有一陰極（cath〇de)zc以及一 陽極（an〇de)ZA，其中陰極ZC係電性連接於基極B，陽極za 係電性連接至接地GND，藉此當基納二極體2被施加一逆向偏 屋’且該逆向偏壓為該基納二極體之一崩潰電壓例如為3 6伏 特或5.6伏特時，可以使基極B之電壓固定於該崩潰電麼例如 為3.6伏特或5.6伏特之值，再類似第一實施例的設計方式可 依序求出第二電阻R2之值及第—電阻幻之值，此不再費述。 时—本創作之液晶顯示裝置之燈條將驅動發光元件之定電流 早疋直接製作在電路板上，再由一電麗源及一接地直接提供驅， 動發光7G件所需之穩定電流，不需使用多迴路驅動積體電路。 t外-也無而使用軟性電路板電性連接多迴路驅動積體電路及 《光7C件又’當增加多組發光元件時只需要延長電壓源線 路及接地線即可提供多組發光元件，比起習知需增加多迴路驅 動積體電路更能節省成本。 上述實施例僅是為了讓本領域技術人員理解本創作而提 (、的最優選的實施模^。本㈣並;^ #限於上述 :内任何本領域技術人員所易於思及的改進均在本創作= 【圖式簡單說明】 第1圖係示意圖說明太名 月本創作第一實施例之液晶顯示裝置之 7 M408048 燈條；以及 第2圖係示意圖說明本創作第二實施例之液晶顯示裝置之 燈條。 【主要元件符號說明】 10 電路板 20 ' 22 、 24 發光元件 26 發光二極體 30、32、34、 40、42、44定電流單元 B 基極 C 集極 E 射極 GND 接地 R1 第一電阻 R2 第二電阻 R3 第三電阻 T 雙載子接面電晶體 VI 電壓源 Z 基納二極體 ZA 陽極 ZC 陰極In a thin film transistor liquid crystal display (TFT LCD), since the liquid crystal itself does not emit light, it is necessary to provide a light required for displaying an image by the backlight module. Since the current products are mostly aimed at light, thin and short, more and more liquid crystal display devices replace the cold cathode fluorescent lamp (CCFL) as a light-emitting diode in a backlight module by using a light emitting diode (LED). element. Generally, a plurality of groups of LED circuits are fabricated on a long-type circuit board to form a light bar, and a driving circuit for driving the LED circuit on the circuit board is separately fabricated on a separate display. On the device circuit board, a multi-finger finger terminal and a connector of a flexible printed circuit (FPC) are used to electrically connect the LED circuit on the circuit board and the driving circuit on the circuit board of the display device. Sexual connections form a complete loop. Conventional drive circuits have the following disadvantages. First, the driving circuit on the display circuit board includes a multi-circuit driving integrated circuit (1C) with a feedback resistor to set the constant current value of the LED circuit, because each LED circuit There is a difference in the internal resistance, which will cause an error in the constant current value flowing through each of the light-emitting diode circuits. * The liquid crystal display does not have different degrees of difference in different blocks, which affects the display quality. Furthermore, the LED circuits on the circuit board are connected in parallel with each other, and the more the circuit is represented, the more flexible circuit boards and connectors are required to electrically connect the LED 2 M408048 body circuit and the driving circuit, thereby causing an increase in cost. Therefore, it is necessary to propose a solution to the problem caused by the separate arrangement of the above-described conventional light-emitting diode circuit and drive circuit. [New Content] One of the aims of the present invention is to provide a light bar of a liquid crystal display device which can reduce the components and costs required for the driving circuit. To achieve the above object, the light bar of the liquid crystal display device according to the present invention comprises a circuit board, at least one light-emitting element, and at least a certain current unit. The at least one light emitting component is disposed on the circuit board. The at least one current unit is disposed on the circuit board for driving the at least one light emitting element. According to the light bar of the liquid crystal display device of the present invention, the constant current unit for driving the light-emitting element is directly fabricated on the circuit board, so that it is not necessary to use the multi-circuit drive integrated circuit, and the utility model does not need to use a flexible circuit board and connect the gastric electrical connection. The loop-driven integrated circuit and the light-emitting element can reduce the cost more than the conventional technology. [Embodiment] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings. Please refer to the figure, which is a schematic diagram showing the light bar of the liquid crystal addition device of the first embodiment of the present invention. The light bar of the liquid crystal display device comprises a circuit ... 〇, a small one light-emitting element (represented by the light-emitting elements 2 〇 '22, 24 in the figure) and at least a certain unit (the constant current unit 3 〇, 32 in the figure) 34 representatives). The illuminants 22, 24 are disposed on the circuit board 10. Each of the light-emitting elements 20, 22, and 24 includes at least a light-emitting diode (in which five light-emitting diodes are connected in series: each of the constant current units 30, 32, and 34 is disposed on the electric plate 1 The flow unit 30 is configured to provide (4) mosquito current to drive the light-emitting component to be applied, and to set the power: M408048 is used to provide a stable constant current to drive the light-emitting element 22, and the constant current unit 34 is used to provide a stable constant current. The light-emitting element 24 is driven. Since the structure and operation of the constant current units 30, 32, and 34 are the same, the following is only a constant current unit; 30 is taken as an example. In the present embodiment, the constant current unit 30 includes a double-carrier connection. A bipolar junction transist〇r (BJT) T, a first resistor, a second resistor R2, and a third resistor 16. The bipolar junction transistor τ has a pole: (base) B, a collector (e〇llect〇r) CW and an emitter E. The two ends of the first resistor # Ri are electrically connected to a voltage source ¥1 and a double carrier junction transistor I, respectively. Base B. Both ends of the second resistor R2 are f-connected to the emitter E of the bipolar junction transistor τ and the ground GND, respectively. The two ends of the three resistors R3 are electrically connected to the base B of the bipolar junction transistor T and the grounding pass. The light emitting device is electrically connected to the collector of the voltage source ¥1 and the bipolar junction transistor τ. Between c. The voltage source VI is provided by the system side, and its power is at least greater than the sum of the voltages required for the maximum brightness of the light-emitting elements. 20, that is, greater than each light-emitting diode. In the present embodiment, the sum of the voltages required for the maximum brightness of at least 5 of the light-emitting diodes 26 is required. For example, if one of the light-emitting diodes 26 produces the largest The voltage required for brightness is 3.5 volts (V), then the voltage source VI must provide at least 3.5 volts *5 = 17 5 volts', for example, 19 volts. If the design base b voltage is 3 6 volts, the base The forward voltage of the pole B and the emitter E is assumed to be 0.6 volt, and the voltage of the emitter E is 3 volts when the bipolar junction transistor τ is turned on, and the second resistor 5 M408048 R2 = 3 volts = 15 () Ohm (Ω). Next, design the value of the first resistor 丨 and the 20th ampere resistor R3 In order to reduce the leakage current, the current flowing through the first resistor R1 and the third resistor R3 should be less than 1 milliamperes (mA), so the value of the first resistor R1 and the value of the third resistor R3 must be selected higher. Level, since the voltage of the base B is 3.6 volts, assuming that the third resistor R3 selects 100 kilo ohms (kD), the current flowing through the third resistor R3 = 3 stone volts = 〇〇 36 milliamperes, representing the flow through the first resistor The 100 kΩ current of R1 is also 0.036 mA, so the first resistor R1 = (19 volts _3·6 volts) g428 0.036 milliamperes kilo ohms. Moreover, the constant current units 32 and 34 respectively supply constant currents to drive the light-emitting elements 22 and 24, and the design principle thereof is the same as that of the constant current unit 30, and details are not described herein again. Please refer to Fig. 2, which is a schematic view showing the light bar of the liquid crystal display device of the second embodiment of the present invention. The light bar of the liquid crystal display device comprises a circuit board 10, at least one light-emitting element (represented by the light-emitting elements 20, 22, 24 in the figure) and at least a certain current unit (represented by constant current units 40, 42, 44 in the figure). The light-emitting elements 20, 22, 24 are attached to the circuit board 10. Each of the light-emitting elements 20, 22, 24 includes at least one light-emitting diode 26, respectively. Each of the constant current units 40, 42, 44 is disposed on the circuit board 10, wherein the constant current unit 40 is configured to provide a stable constant current to drive the light emitting element 20, and the constant current unit 42 is configured to provide a stable constant current to drive the light. Element 22, constant current unit 44 is used to provide a stable constant current to drive light emitting element 24. M408048 The second embodiment differs from the first embodiment in that the constant current units 40, 42, 44 of the second embodiment are replaced by a Zener diode z in the constant current of the first embodiment. The third resistor R3 of the cells 30, 32, 34. Taking the constant current unit 40 as an example, the Zener diode z has a cathode (cath〇de) zc and an anode (an 〇de) ZA, wherein the cathode ZC is electrically connected to the base B, and the anode za is electrically connected. Connected to ground GND, whereby when the Zener diode 2 is applied with a reverse bias, and the reverse bias is one of the voltages of the Zener diode, for example, 36 volts or 5.6 volts, The voltage of the pole B is fixed to the value of the crash power, for example, 3.6 volts or 5.6 volts, and the value of the second resistor R2 and the value of the first resistor are sequentially determined similarly to the design of the first embodiment. More details. At the same time, the light bar of the liquid crystal display device of the present invention will directly drive the constant current of the light-emitting element on the circuit board, and then directly provide a stable current required for driving the 7G piece by a power source and a ground. There is no need to use a multi-loop drive integrated circuit. T-outside - no use of flexible circuit board to electrically connect multi-circuit drive integrated circuit and "Light 7C parts" When adding multiple sets of light-emitting elements, only need to extend the voltage source line and ground line to provide multiple sets of light-emitting elements. More cost savings than adding a multi-loop drive integrated circuit. The above-described embodiments are only for the purpose of understanding the present invention by those skilled in the art, and the most preferred embodiments are: (4) and ^ # are limited to the above: any improvement that can be easily considered by those skilled in the art is in this Creation = [Simplified description of the drawings] Fig. 1 is a schematic view showing the 7 M408048 light bar of the liquid crystal display device of the first embodiment of the creation of the name of the moon; and the second figure is a schematic view showing the liquid crystal display device of the second embodiment of the present creation Light bar. [Main component symbol description] 10 Circuit board 20 ' 22 , 24 Light-emitting element 26 Light-emitting diode 30, 32, 34, 40, 42, 44 Constant current unit B Base C Collector E Emitter GND Ground R1 first resistor R2 second resistor R3 third resistor T double carrier junction transistor VI voltage source Z sense diode ZA anode ZC cathode