【正文】 些因素很難去假設和模仿。 also measured. Conclusions are drawn in Section V. 第五部分將引出結論。 connections topology, and wiring parasitics. Hereafter, Section 此后，在第二部分，分析了振蕩和電磁干擾在放光二極管驅動中的影響 。 wire inductance and connector capacitance. Usually, in car environment 通常 ,在汽車環(huán)境中，幾米長電線使用 ,就會生成強烈振蕩。 their cost is decreasing. However, LEDs are pretty difficult to 事實上，發(fā)光二極管是很難驅動，因此相比較普通燈泡，發(fā)光二極管驅動要求更多的技巧和控制功能 。 moreover 此外 ，它有很高的 功率效率，它是可編程的，還可以配置用于線性的調(diào)節(jié)器 。 Current Slope Control techniques are integrated onchip. This letter 這篇文章討論了設計于集合 于高電壓的互補金屬氧化半導體上的驅動技術， discusses the driver design integrating in high voltage CMOS technology, the digital circuitry for programming and electronic 用于編程和電子控制單元連接的數(shù)字電路以及功率元件提高到 10瓦特。 control units interfacing, and the power devices up to 10W. Experimental 同時 也展示了不同功率等級使用的發(fā)光二極管和與不同類型的連接時的實驗特征。 it has high power efficiency, it is programmable, and can be configured to work as a linear regulator (for low current LEDs) or in switch mode (for higher power LEDs). （用于弱電流發(fā)光二極管）或轉換模式（用于高功率發(fā)光二極管） IndexTerms—Automotive electronics, high voltage (HV)CMOS, integrated circuit (IC), LED driver. 關鍵詞 — 汽車用電子設備，高電壓互補金屬氧化物半導體，集成電路 LED驅動 I. INTRODUCTION 1：介紹 IN the last few years LED technology experienced a very fast 在過去的幾年中，發(fā)光二極管技術 在汽車照明應用中替代普通燈泡 經(jīng)歷了一個非常快速的進步時代， and important growth, superseding the bulb technology in automotive lighting applications [1]. To achieve the harsh requirement of CO2 emission and reduce the fuel consumption, car manufacturer must reduce the total power consumption. The 為了實現(xiàn)了嚴格的二氧化碳排放要求和降低了燃料的消耗 , 汽車制造商必須減少總的功率消耗。 drive and therefore LEDdrivers require many tricks and control functions pared to bulb drivers. Moreover, automotive 而且，汽車應用程序需要緊湊和低成本的解決方案 ,靈活 足夠的數(shù)字電子控制單元界面， applications require pact and lowcost solutions, flexible enough to be interfaced to digital electronic control units (ECU) and to cope with different wiring configurations and relevant 同時需要應付不同的布線配置和相關拓展。 few meters long wires are used, generating dumped oscillations. Such oscillations and the associated overcurrent and overvoltage levels reduce the LED life time and its efficiency 這種振蕩和與之相關的過電流和過電壓會降低發(fā)光二極管壽命及其效率。 II analyzes ringing and EMI problems in LED driving. Section III presents the design of the new LED smart driver focusing on 第三部分介紹了一款新設計的智能發(fā)光二極管驅動的顯著特征。 II. RINGING AND EMI PROBLEMS IN LED DRIVING 二 .振蕩和電磁干擾在發(fā)光二極管驅動中的影響 文獻翻譯 021309208 吳驍奕 At stateoftheart LED, driving is implemented using lowdrop out linear regulators, which are limited to LEDs of few tens of milliamperes, or more powerefficient switching solutions at higher current levels 在最開始的 LED,開車是使用低輸出線性穩(wěn)壓器 ,僅限于幾十毫安級的發(fā)光二極管 ,或更省電轉換解決方案用在更高的電流水平。 depend on environmental and parasitic ponents that are difficult to predict and bulbs are easily modeled as 而電燈泡卻很容易模仿因為它有線性的正溫度系數(shù)并且寄生成分對它的影響比較小。 and life time and creating lighting disturbs. This behavior 如果發(fā)光二極管沒有恰當?shù)谋或寗拥脑?這個行為會導致振蕩和高強度的電流尖脈沖。 A parison based on experimental measurements, between 一個在二瓦特的燈泡和 （大概 10厘米長）發(fā)光二極管的比較實驗中顯示在圖 1和圖 2中 。 [從圖 1a圖 2a可以看出 ] bulb does not change significantly with the wire length [see Figs. 1(a) and 2(a)] while the transient of the current in the 而發(fā)光二極管的瞬間電流缺有顯著的差異。 adapt its behavior working as linear regulator or as a switching one, depending on a programmable threshold. III. FLEXIBLE LED DRIVER IC 三 . 靈活的發(fā)光二極管驅動集成電路 With respect to the bulb lamp driver shown in [11], [12] the 關于指示燈驅動器了，智能 LED驅動必須滿足嚴酷的汽車環(huán)境約束。 圖 驅動集成電路的體系結構和詳細電路 文獻翻譯 021309208 吳驍奕 The driving of LEDs has required the implementation of specific techniques to limit the undesired effects of wiring parasitics, 發(fā)光二極管的驅動要求實施特定的技術來限制布線寄生現(xiàn)象帶來的不良影響。 transconductance amplifier (OTA) block: the architecture 這個設計基于一個 is based on a voltage regulation loop inserted inside a linear loop providing the current control capability. 插入在一個線性循環(huán)的電壓調(diào)節(jié)回路以提供當前的控制能力。 highlighting the LED driver circuit, and particularly the power MOS and its protection diode in Fig. 4, which occupy most of the LED driver area. 特別的在圖四中的 MOS材料和二極管的保護，占絕了絕大部分的發(fā)光二極管驅動電路。 means of a programmable resistive path to ground. That path is highly resistive to limit to very low value the current flowing through the LED. Finally, if the user switch is ON but the 這條道路的高電阻是用來限制非常低的電流來通過發(fā)光二極管，如果用戶開關打開但電源開關關閉，那么輸出電壓將強迫輸出為電源的額定電壓。 phenomena can be detected by paring the measured current and temperature values (through an onchip temperature sensor) with proper thresholds. All reference and threshold levels are 同樣的過電流和超溫現(xiàn)象是可以探測到的測量的電流和溫度的值 (通過一個芯片上的溫度傳感器 )和適當?shù)拈撝当容^。 fraction of the power MOS output current and, through the HV and LowVoltage (LV) current mirrors in Fig. 4, MOSMA反射小部分功率從 MOS輸出電流 ,如圖四通過高壓和低壓 (LV)電流反射鏡鏡， pares it to the Iref current value (generated through onchip bandgap circuit). 比較其當前值 (通過芯片上的帶隙電路生成 Iref)。 current loop control switches to the OFF state the power MOS. The MOS MB can be forced back in OFF state, and hence the 同時強制電源 MOS起作用，如圖四用來進行邏輯控制。在線性莫模型中， Iref acts as a protection threshold: if Imir is over Iref then MB is Iref擔當著一個保護的臨界值：當 Imir超過了 Iref，那么 MB會打開，電源 MOS會關