201012297 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種串聯諧振點燈電路，特別是指一種利用獨立 電感串聯壓電變壓器之壓電式串聯諳振點燈電路。 【先前技術】 冷陰極燈管（Cold Cathode Fluorescent Lamp ; CCFL)發光原 理與一般日光燈相似，其發光原理為，當高壓電由電極端輸入後，管 内少數電子分子咼速撞擊電極，此時產生二次電子發射，開始放電時， 電子與水銀原子發生碰撞’水銀原子受激發輻射出2537nm之紫外 ® 光，紫外光激發塗佈於管壁上之螢光粉而產生相對色溫之可見光。一 般除可應用於顯示器、個人數位助理、數位相機及手機等，更是液晶 顯示器不可或缺的背光源材料之一。 然而，由於液晶顯示的應用逐漸擴展，其尺寸也逐漸加大，因此 背光源所使用的冷陰極燈管數目也必須隨之增加，以維持相同或較高 的亮度。基於亮度分佈均勻和延長燈管壽命要求，燈管電流的絕對值 和相對差異要嚴謹控制。一種習用的多燈管模組，係利用在燈管上並 聯傳統的線圈型升壓變壓器，其缺點是效率不高，而且線圈的財壓不 足，很容易會因為高壓而跳電擊穿，導致短路燒毁，具有極高的危險 ❹性。而另一種多燈管模組之架構，如第1圖所繪示，其燈管1〇〇之間 的電流差異是由串接在燈管100高壓端的電容器110來補償，因此會 造成很大的漏電流，效率並不高，而電容器110的耐壓性不足，失效 模式會是電容器110爆炸，容易導致失火的危險。 【發明内容】 鑒於以上的問題’本發明的主要目的在於提供一種壓電式串聯譜 振點燈電路，乃利用壓電變壓器本身所具有的電容特性作為壓電電 容，來構成電感串聯壓電變壓器之諧振點燈電路，可以滿足低漏電、 點燈效率高與電流平衡之需求。 5 201012297 本發明的P目的在於提供-種壓電式串聯譜振點燈電路，藉由 壓電變壓器取代了傳統點燈電路中的電容器或線圈型升壓變壓器，不 但體積小，具有優越的電氣效能，並可避免因耐壓性不足造成故障與 過熱的危險’其可靠性高，極具有市場競爭優勢。 、 本發明的又-目的在於提供—種壓電式㈣譜振點燈電路，利用 串聯的連接方式係可減少線路長度，使最終產品尺寸達到精簡化。 因此，為達上述目的，本發明所揭露之壓電式串聯諧振點燈電路， 是將原應用於超音波震盈器的大功率壓電陶变震盈片轉而應用在諸振 點燈電路之安定器及換流器中作為壓電電容，此諧振點燈電路具有升 ❹壓比會隨著負載的内阻抗值來變動的特性，非常適合應用在燈管的驅 動上。當，管尚未啟動時，可等效為開路狀態，此時諧振點燈電路可 以供給很高的升㈣來制啟動料；當奸啟動後，等效阻抗值下 降而電路升壓比也會因此下降，使燈管正常的操作在穩態中。 —同時，本發明能夠應用於多燈管電流平衡，透過固定頻率使壓電 電容的等效電路中内阻抗值固定，形成一固定電流通過燈管，當串聯 ，管上的壓電電容與其他燈管上的壓電電容電氣特性接近時其内阻 抗值接近，使每一支燈管中的電流一致，而達到管電流平衡。 。另外，本發明將壓電電容可與獨立電感搭配來構成諧振點燈電路 醫之架構’係適用於全橋電路下的雙高壓點燈，當然，亦適用於半橋電 路下的單高壓點燈。 為使對本發明的目的、特徵及其功能有進一步的了解，茲配合圖 式詳細說明如下： 【實施方式】 请參照第2圖，係繪示本發明之實施例所提供之壓電式串聯諧振 ，燈電路的示意圖，主要包含多組串接於兩I電電容彳0、2()之間的冷 陰極燈管30，每一組冷陰極燈管30彼此並聯，再和諧振電感4〇作串 聯。此壓電式串聯諧振點燈電路乃是湘壓電變壓器本身所具有的電 6 201012297 容特性作為壓電電容10與20，並與諧振電感40串聯，構成一電感串 聯壓電變壓11H麟f路，可藉㈣整雜紐40及壓電變壓器 之電容值而達到升電壓點燈的功能。 本實施例所揭露之壓電電容1〇(壓電電容10與20之結構相同， 在此僅以壓電電容1〇為代表），如第3圖所示，是以壓電材質製作一 圓板形狀的壓電基材11，當然，其形狀亦可以為方形或矩形，再以銀 膠、鋼膏或錄f製作同樣為圓形的導電層12、13於壓電基材^的整 個或部分的上表面與下表面，以構成壓電電容1〇之兩極來引導電流。 在此，請參閱第10圖，為壓電電容10或20之等效電路；等效電路 Ο 中繪示有等效電阻R、等效電感l、以及分別表示力學特性與電特性 的等效電容Ca與Cb»與一般電容器或線圈型升塵變壓器不同處在 於，本實施例之壓電電容1〇或20的漏電流小、耐壓性高，沒有過熱 起火的危險，其可靠性高，亦可提供倍數增加的輸出功率，使點燈效 率提高許多；其次，由於壓電電容的體積小、封裝厚度薄，再加上使 用串聯連接諧振電感、壓電電容與燈管的配置方式，將可以減少整體 線路長度，使最終產品尺寸達到精簡化；同時，與並聯連接方式相較， 本發明利用串聯連接係可以維持較低的溫度，產生較小的損耗。 並且，此廢電式串聯諧振點燈電路係可以有效維持管電流平衡； 參當輸入直流脈波t壓源轉為交流去驅動電路，壓電電容會將低壓提升 到點亮燈管所需的咼壓，由於燈管阻抗特性差異，燈管電流不一致會 造成背光亮度不均勻和降低燈管壽命’因此，本發明利用固定頻率來 驅動諧振點燈電路，使壓電電容的等效電路中内阻抗值固定，而形成 一固定電流通過燈管，當串聯燈管上的壓電電容與其他燈管上的壓電 電容之電氣特性接近時’其内阻抗值接近，使每一支燈管中的電流一 致，換句話說’即達到多燈管電流平衡的功能。 另外，本實施例更透過設置一輔助壓電電容5〇並聯於諧振電感 40和多組燈管30之間（見第2圖），而形成一串並聯諧振點燈電路， 7 201012297 除了發揮啟動的用途之外’更可調整其電容值的大小，使輸出電流的 大小產生微調，使輸出功率達到最佳化。當點燈時電壓會瞬間昇高， 點燈完負載内阻抗變小時，升壓比會下降，所以輸出會進行調整，能 減少額外的電力消耗。 上述實施例中，係每一支燈管30搭配兩顆壓電電容與2〇，並 搭配一顆諧振電感40而構成半橋諧振電路，可減少生產成本，極具有 價格競爭的優勢。當然，若搭配二顆諧振電感4〇、60來構成全橋諧振 電路，即可以推動更高功率之輸出，如第4圖所示。 ❹ 另外，本發明可適用於單支的冷陰極燈管（CCFL)、外部電極螢 光燈板（EEFL)、省電燈泡或發光二鋪（LED)，亦可適用於並聯的 多支冷陰極燈管、外部電極螢光燈板、省電燈泡或發光二極體。請參 閱第5圖~第7@，分麟示本發明之壓電式㈣諧振點燈電路使用在 外部電極螢紐板7G、發光二極體80與省電燈泡90之示意圖。當然， 其架構皆可為半橋或全橋諧振電路》 … 再者，本發明亦可適用於大尺寸的背光板（譬如42吋以上），而 大尺寸身光板往往需要安裝長燈管（譬如長度1m以上的燈管），其燈 管内電容損耗率大，容易造成燈管亮度的差異，這時每支燈管就需要 個別獨立的諧振電感及塵電電容來平衡電容。請參閱第8圏與第9圖， ^別以雙高壓（全橋）與單高壓（半橋）輸入的壓電式串聯譜振點燈 電路200與300為例，每一支燈管3〇分別串聯於兩顆壓電電容、 20與兩顆譜振電感40、6〇之間（見第8圖），或者每一支燈管加 /刀別和-顆麼電電容1〇與一顆譜振電感4〇作串聯 (見第Θ圖）。 亚哪 雖然本發明以前述之實關揭露如上，然其並_以限定本發 明之精神和範圍内，所為之更動與潤飾’均屬本發 本發明所狀之保護範圍請參考所附之申請 8 201012297 【圖式簡單說明】 第1圖係先前技術之使用一般電容器之多燈管模組； 第2圖係本發明實施例所提供之壓電式串聯諧振點燈電路； 第3圖係本發明實施例所提供之壓電電容的元件結構； 第4圖係本發明實施例所提供之全橋輸出的壓電式串聯諧振點燈電 路； 第5圖係本發明實施例之壓電式串聯諳振點燈電路使用在外部電極螢 光燈板之示意圖； 第6圓係本發明實施例之壓電式串聯諧振點燈電路使用在發光二極體 % 之示意囷； 第7圓係本發明實施例之壓電式串聯諧振點燈電路使用在省電燈泡之 示意圖； 第8圖係本發明實施例所提供之全橋輸入的壓電式串聯諧振點燈電 路； 第9圖係本發明實施例所提供之半橋輸入的壓電式串聯諧振點燈電 路；以及 第10圖係本發明實施例所提供之壓電電容之等效電路。 【主要元件符號說明】 ® 10壓電電容 圓板基材 12導電層 13導電層 20壓電電容 30冷陰極燈管 40諧振電感 50辅助壓電電容 60諧振電感 9 201012297 70外部電極螢光燈板 80發光二極體 90省電燈泡 100燈管 110電容器 200雙高壓輸入的壓電式串聯諧振點燈電路 300單高壓輸入的壓電式串聯諧振點燈電路201012297 IX. Description of the Invention: [Technical Field] The present invention relates to a series resonant lighting circuit, and more particularly to a piezoelectric series resonant lighting circuit using a series inductor of a separate inductor. [Prior Art] The principle of luminescence of Cold Cathode Fluorescent Lamp (CCFL) is similar to that of general fluorescent lamps. The principle of illuminating is that when high voltage electricity is input from the electrode end, a small number of electron molecules in the tube idly hit the electrode. Secondary electron emission, when the discharge starts, the electron collides with the mercury atom. The mercury atom is excited to emit ultraviolet light of 2537 nm, and the ultraviolet light excites the phosphor powder coated on the tube wall to generate visible light of relative color temperature. Generally, it can be applied to displays, personal digital assistants, digital cameras, and mobile phones. It is also one of the indispensable backlight materials for liquid crystal displays. However, as the application of liquid crystal displays is gradually expanding and its size is gradually increasing, the number of cold cathode lamps used in backlights must also be increased to maintain the same or higher brightness. Based on uniform brightness distribution and extended lamp life requirements, the absolute and relative differences in lamp current must be carefully controlled. A conventional multi-lamp module adopts a conventional coil type step-up transformer connected in parallel with a lamp tube, and has the disadvantages that the efficiency is not high, and the coil has insufficient financial pressure, and it is easy to jump due to high voltage and cause a short circuit. Burned, it is extremely dangerous and dangerous. The structure of another multi-lamp module, as shown in Fig. 1, the difference in current between the lamps 1 is compensated by the capacitor 110 connected in series at the high voltage end of the lamp 100, thus causing a large The leakage current is not high in efficiency, and the voltage resistance of the capacitor 110 is insufficient, and the failure mode may cause the capacitor 110 to explode, which may easily cause a fire. SUMMARY OF THE INVENTION In view of the above problems, the main object of the present invention is to provide a piezoelectric series-series spectral lighting circuit, which utilizes the capacitance characteristics of the piezoelectric transformer itself as a piezoelectric capacitor to form an inductive series piezoelectric transformer. The resonant lighting circuit can meet the requirements of low leakage, high lighting efficiency and current balance. 5 201012297 The purpose of P of the present invention is to provide a piezoelectric series series spectrum lighting circuit, which replaces a capacitor or a coil type step-up transformer in a conventional lighting circuit by a piezoelectric transformer, and has a small size and superior electrical performance. Efficacy, and can avoid the danger of failure and overheating due to insufficient pressure resistance. It has high reliability and is highly competitive in the market. Further, another object of the present invention is to provide a piezoelectric (four) spectral vibration lighting circuit, which can reduce the length of the line by using a series connection method, and the final product size can be simplified. Therefore, in order to achieve the above object, the piezoelectric series resonant lighting circuit disclosed in the present invention converts a high-power piezoelectric ceramic seismic sheet originally applied to an ultrasonic oscillator into a plurality of vibration lighting circuits. As a piezoelectric capacitor in the ballast and the inverter, the resonant lighting circuit has a characteristic that the hoisting voltage ratio varies with the internal impedance value of the load, and is very suitable for application to the lamp. When the tube has not been started, it can be equivalent to an open state. At this time, the resonant lighting circuit can supply a very high rise (four) to start the material; after the start, the equivalent impedance value decreases and the circuit boost ratio also Drops, allowing the lamp to operate normally in steady state. At the same time, the invention can be applied to multi-lamp current balance, and the internal impedance value of the equivalent circuit of the piezoelectric capacitor is fixed through a fixed frequency to form a fixed current through the lamp tube, when connected in series, the piezoelectric capacitor on the tube and other When the electrical characteristics of the piezoelectric capacitor on the lamp are close, the internal impedance value is close, so that the current in each tube is uniform, and the tube current balance is achieved. . In addition, the present invention combines a piezoelectric capacitor with an independent inductor to form a resonant lighting circuit. The system is suitable for dual high-voltage lighting under a full-bridge circuit. Of course, it is also suitable for a single high-voltage lighting under a half-bridge circuit. . In order to further understand the objects, features and functions of the present invention, the following detailed description will be made with reference to the drawings: [Embodiment] Referring to FIG. 2, a piezoelectric series resonance provided by an embodiment of the present invention is illustrated. The schematic diagram of the lamp circuit mainly comprises a plurality of sets of cold cathode lamps 30 connected in series between two I capacitors 彳0, 2(), each group of cold cathode lamps 30 being connected in parallel with each other, and then reacting with the resonant inductor 4 In series. The piezoelectric series resonant lighting circuit is the electric capacitor of the piezoelectric transformer itself. The capacitance characteristics are used as the piezoelectric capacitors 10 and 20, and are connected in series with the resonant inductor 40 to form an inductor series piezoelectric transformer 11H. Road, you can borrow (four) the complex capacitor 40 and the capacitance value of the piezoelectric transformer to achieve the function of rising voltage lighting. The piezoelectric capacitor disclosed in this embodiment has the same structure (the piezoelectric capacitors 10 and 20 have the same structure, and is represented only by the piezoelectric capacitor 1 )). As shown in FIG. 3, a circular plate is made of a piezoelectric material. The shape of the piezoelectric substrate 11, of course, the shape may also be square or rectangular, and then the same circular conductive layers 12, 13 are made of silver glue, steel paste or recording f to the whole or part of the piezoelectric substrate The upper surface and the lower surface form a pole of the piezoelectric capacitor 1 引导 to guide the current. Here, please refer to Fig. 10, which is the equivalent circuit of the piezoelectric capacitor 10 or 20; the equivalent circuit 绘 shows the equivalent resistance R, the equivalent inductance l, and the equivalent of the mechanical and electrical characteristics, respectively. The capacitances Ca and Cb» are different from the general capacitor or the coil type dust-removing transformer in that the piezoelectric capacitor 1〇 or 20 of the present embodiment has a small leakage current and high pressure resistance, and there is no danger of overheating and fire, and the reliability thereof is high. It can also provide multiple output power to increase the lighting efficiency. Secondly, due to the small size of the piezoelectric capacitor and the thin package thickness, coupled with the use of series connection resonant inductor, piezoelectric capacitor and lamp configuration, The overall line length can be reduced to achieve a simplified final product size; at the same time, the present invention utilizes a series connection system to maintain a lower temperature and produce less loss than a parallel connection. Moreover, the waste electric series resonant lighting circuit can effectively maintain the tube current balance; the input DC pulse t source is converted into an AC drive circuit, and the piezoelectric capacitor will raise the low voltage to the required lamp. Rolling, due to the difference in lamp impedance characteristics, the inconsistent lamp current will cause uneven brightness of the backlight and reduce lamp life. Therefore, the present invention uses a fixed frequency to drive the resonant lighting circuit so that the equivalent circuit of the piezoelectric capacitor is within The impedance value is fixed, and a fixed current is passed through the lamp tube. When the piezoelectric capacitance on the series lamp tube is close to the electrical capacitance of the piezoelectric capacitor on the other lamp tube, the internal impedance value is close to each lamp tube. The current is consistent, in other words 'that is, the function of multi-lamp current balance. In addition, in this embodiment, an auxiliary piezoelectric capacitor 5 is further connected between the resonant inductor 40 and the plurality of lamps 30 (see FIG. 2) to form a series of parallel resonant lighting circuits, 7 201012297 In addition to the use of 'more adjustable size of its capacitance value, the output current is fine-tuned to optimize the output power. When the light is turned on, the voltage will rise instantaneously. When the internal impedance of the load is reduced, the boost ratio will decrease, so the output will be adjusted to reduce the extra power consumption. In the above embodiment, each of the lamps 30 is matched with two piezoelectric capacitors and two turns, and is combined with a resonant inductor 40 to form a half-bridge resonant circuit, which can reduce the production cost and has the advantage of price competition. Of course, if you combine two resonant inductors 4〇, 60 to form a full-bridge resonant circuit, you can drive higher power output, as shown in Figure 4. ❹ In addition, the present invention can be applied to a single cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp panel (EEFL), a power saving bulb or a light emitting diode (LED), and can also be applied to multiple cold cathode lamps in parallel. Tube, external electrode fluorescent lamp board, power saving light bulb or light emitting diode. Referring to Fig. 5 to Fig. 7, the piezoelectric (4) resonant lighting circuit of the present invention is used in the external electrode fluorescent plate 7G, the light emitting diode 80 and the power saving bulb 90. Of course, the architecture can be a half-bridge or full-bridge resonant circuit. Furthermore, the present invention can also be applied to a large-sized backlight (such as 42 吋 or more), and a large-sized light-emitting panel often requires a long lamp (for example, For lamps with a length of 1 m or more, the loss of capacitance in the lamp tube is large, which is likely to cause a difference in brightness of the lamp. At this time, each lamp tube needs separate independent resonant inductors and dust electric capacitors to balance the capacitance. Please refer to pictures 8 and 9 respectively. For example, the piezoelectric series series lighting circuit 200 and 300 with double high voltage (full bridge) and single high voltage (half bridge) input, for example, each lamp 3〇 Connected in series between two piezoelectric capacitors, 20 and two spectral inductors 40, 6〇 (see Figure 8), or each tube plus / knife and - the capacitor is 1 〇 and one The spectral inductance 4 is connected in series (see Figure )). Although the present invention is disclosed above in the foregoing, it is intended to be within the spirit and scope of the present invention, and the modifications and refinements of the present invention are the scope of protection of the present invention. 8 201012297 [Simplified description of the drawings] Fig. 1 is a multi-lamp module of the prior art using a general capacitor; Figure 2 is a piezoelectric series resonant lighting circuit provided by an embodiment of the present invention; The device structure of the piezoelectric capacitor provided by the embodiment of the invention; FIG. 4 is a piezoelectric series resonant lighting circuit of the full bridge output provided by the embodiment of the present invention; FIG. 5 is a piezoelectric series connection according to the embodiment of the present invention; FIG. 6 is a schematic diagram of a piezoelectric series resonant lighting circuit according to an embodiment of the present invention used in a light-emitting diode. The seventh circular system is the present invention. The piezoelectric series resonant lighting circuit of the embodiment is used in the schematic diagram of the power saving bulb; FIG. 8 is the full-bridge input piezoelectric series resonant lighting circuit provided by the embodiment of the present invention; FIG. 9 is the embodiment of the present invention Proposed The half-bridge series resonant input piezoelectric lighting circuit; and Fig. 10 based embodiment of the invention provided equivalent circuit of the piezoelectric capacitor. [Main component symbol description] ® 10 Piezoelectric capacitor disk substrate 12 Conductive layer 13 Conductive layer 20 Piezoelectric capacitor 30 Cold cathode lamp 40 Resonant inductor 50 Auxiliary Piezoelectric capacitor 60 Resonant inductor 9 201012297 70 External electrode fluorescent lamp board 80 light-emitting diode 90 energy-saving bulb 100 lamp 110 capacitor 200 double high-voltage input piezoelectric series resonant lighting circuit 300 single high-voltage input piezoelectric series resonant lighting circuit
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