【摘要】：在全球能源危機(jī)日益凸顯的背景下,發(fā)光二極管(LED)照明以其高效節(jié)能、綠色環(huán)保的絕對優(yōu)勢已經(jīng)發(fā)展成為了當(dāng)前最具潛力的照明方式之一。LED的普遍使用也推動了其驅(qū)動電源的開發(fā)和研究,如何提高驅(qū)動電源的安全性和驅(qū)動性能是當(dāng)前這一領(lǐng)域的研究重點。調(diào)光技術(shù)的應(yīng)用不僅可以提高我們的視覺效果,改善生活質(zhì)量,而且可以進(jìn)一步的節(jié)約能源,延長LED的使用壽命。目前市場上采用TRIAC調(diào)光的日光燈和白熾燈占大多數(shù),因此只有設(shè)計出能夠兼容TRIAC調(diào)光的LED驅(qū)動器才可以節(jié)省成本并迅速占領(lǐng)市場。本文基于電流采樣技術(shù),設(shè)計了一款具有調(diào)光功能的LED驅(qū)動芯片。該芯片具有高的功率因數(shù),可實現(xiàn)TRIAC調(diào)光器對輸出電流的精確控制。芯片內(nèi)部的整個反饋環(huán)路是由數(shù)字電路實現(xiàn),減小了由于工藝偏差而導(dǎo)致的誤差。采用先進(jìn)的電流采樣技術(shù),實現(xiàn)了對輸入線電壓的監(jiān)測,減少了芯片的引腳數(shù)量,節(jié)約面積和成本。基于TRIAC切角測量技術(shù),設(shè)計出一個頻率可調(diào)的時鐘振蕩電路,其頻率是跟隨輸入線電壓頻率的變化而變化的,兩者之間滿足一個定量關(guān)系,從而獲得了無閃爍的恒流輸出控制。巧妙的設(shè)計了導(dǎo)通時間延長電路,用來增強(qiáng)過零檢測的準(zhǔn)確度,過零比較器采用低功耗設(shè)計,減少了芯片的耗電。芯片的應(yīng)用范圍廣泛,AC輸入線電壓在85 V~265 V,頻率在47 Hz~63 Hz范圍內(nèi)變化時,均能正常的工作。論文對芯片內(nèi)部的核心模塊:電流采樣電路、過零檢測及過流檢測電路、導(dǎo)通時間延長電路、切角測量模塊進(jìn)行了詳細(xì)的分析和仿真驗證。最后使用臺積電公司的0.5μm BCD工藝庫,利用Hspice軟件在25℃下,對芯片整體及其拓?fù)浣Y(jié)構(gòu)進(jìn)行了仿真,仿真結(jié)果表明本文所設(shè)計的基于電流采樣,帶可控硅調(diào)光,恒流輸出的LED驅(qū)動芯片能夠很好的符合各項指標(biāo)要求,即使在線網(wǎng)電壓存在波動時,也不會出現(xiàn)閃爍的問題。
[Abstract]:Under the background of the global energy crisis, LED (LED) lighting is highly efficient and energy saving. The absolute advantage of green environmental protection has developed into one of the most potential lighting methods at present. The widespread use of LED has also promoted the development and research of its driving power supply. How to improve the safety and performance of power supply is the focus of this field. The application of dimming technology can not only improve our visual effect, improve the quality of life, but also further save energy, prolong the service life of LED. At present, the majority of fluorescent and incandescent lamps use TRIAC dimming in the market, so only by designing a LED driver that can be compatible with TRIAC dimming can it save costs and quickly occupy the market. Based on current sampling technology, a LED driver chip with dimming function is designed in this paper. The chip has high power factor and can accurately control the output current of TRIAC dimmer. The whole feedback loop in the chip is realized by the digital circuit, which reduces the error caused by the process deviation. Using advanced current sampling technology, the input line voltage is monitored, the number of pins is reduced, and the area and cost are saved. A clock oscillating circuit with adjustable frequency is designed based on the TRIAC tangent measurement technique. The frequency of the circuit changes with the change of the input line voltage frequency, and the relationship between them satisfies a quantitative relationship, thus the constant current output control without scintillation is obtained. The on-time circuit is designed to enhance the accuracy of zero-crossing detection. The zero-crossing comparator is designed with low power consumption, which reduces the power consumption of the chip. The chip has a wide range of applications. When the input voltage of AC is 85 V / 265V and the frequency varies from 47 Hz~63 Hz to 47 Hz~63 Hz, it can work normally. In this paper, the core modules of the chip, such as current sampling circuit, zero-crossing detection and current crossing detection circuit, on-time prolonging circuit, cutting angle measurement module, are analyzed and simulated in detail. Finally, using the 0.5 渭 m BCD process library of TSMC and using Hspice software at 25 鈩，

本文編號：2279552