Advancements in board assembly, PCB layout anddigital IC integration have produced a new generationof densely populated, high performance systems. Theboard-mounted point-of-load (POL) DC/DC power suppliesin these systems are subject to the same demandingsize, high power and performance requirements asother subsystems. The rigorous new POL demands aredifficult to meet with traditional controller or regulatorICs, or power modules.
上傳時(shí)間: 2014-12-24
上傳用戶:lbbyxmraon
A number of conventional solutions have been available forthe design of a DC/DC converter where the output voltageis within the input voltage range—a common scenarioin Li-Ion battery-powered applications—but none werevery attractive until now. Conventional topologies, suchas SEPIC or boost followed by buck, have numerousdisadvantages, including low effi ciency, complex magnetics,polarity inversion and/or circuit complexity/cost. TheLTC®3785 buck-boost controller yields a simple, effi cient,low parts-count, single-converter solution that is easyto implement, thus avoiding the drawbacks associatedwith traditional solutions.
上傳時(shí)間: 2013-10-21
上傳用戶:ljt101007
Speed and accuracy don’t always go hand-in-handin DC/DC converter systems—that is, until now. TheLTC3811 is a dual output, fi xed frequency current modeDC/DC switching regulator controller designed for one oftoday’s most demanding power supply applications: highcurrent, low voltage processor core supplies.
上傳時(shí)間: 2013-11-21
上傳用戶:aix008
DC-link Automotive: MKP1849 (Customized)電動(dòng)汽車電驅(qū)直流母線電容(顧客訂制品)MKP1849系列.MKP1849-可集成母線排,大大降低了寄生電感,提高了系統(tǒng)穩(wěn)定性。
標(biāo)簽: DC-LINK 電動(dòng)汽車 電容
上傳時(shí)間: 2013-10-13
上傳用戶:nanfeicui
交一直一交變頻器的中間直流環(huán)節(jié)如果是用大電容平波通常稱為電壓源型變頻器。如果分開來稱呼,則其后端逆變器部分叫電壓源逆變器(VSI),產(chǎn)品GB和IEC標(biāo)準(zhǔn)也是這種稱呼。其前端整流部分對(duì)電網(wǎng)而言是— 個(gè)諧波源,也就叫電壓型諧波源。與此相對(duì)照,交一直一交變頻器的中間直流環(huán)節(jié)如果用大電感平波就分別稱為電流源型變頻器、電流源逆變器(CSD、電流源型諧波源。之所以要特別區(qū)分變頻器為電壓源和電流源兩大類是因?yàn)樗麄兊慕涣鬏斎腚娏鞑ㄐ魏妥冾l后輸出的交流電壓和交流電流的波形及性能都有很大的不同。
上傳時(shí)間: 2013-11-03
上傳用戶:xitai
AN22 details the theoretical and application aspects of the LT1088 thermal RMS/DC converter. The basic theory behind thermal RMS/DC conversion is discussed and design details of the LT1088 are presented. Circuitry for RMS/DC converters, wideband input buffers and heater protection is shown.
標(biāo)簽: 100 MHz RMS 轉(zhuǎn)換
上傳時(shí)間: 2013-10-16
上傳用戶:china97wan
The LTM4601 DC/DC μModule regulator is a completehigh power density stepdown regulator for up to 12Acontinuous (14A peak) loads. The device is housed ina small 15mm ¥ 15mm ¥ 2.8mm LGA surface mountpackage, thus the large power dissipation is a challengein some applications. This thermal application note willprovide guidelines for using the μModule regulator inambient environments with or without air fl ow. Loadcurrent derating curves are provided for several inputvoltages and output voltages versus ambient temperatureand air fl ow.
上傳時(shí)間: 2013-10-19
上傳用戶:bakdesec
什么是DC/DC 轉(zhuǎn)換器? 什么是DC(Direct Current)呢?它表示的是直流電源,諸如干電池或車載電池之類。家庭用的100V電源是交流電源(AC) 。若通過一個(gè)轉(zhuǎn)換器能將一個(gè)直流電壓(3.0V)轉(zhuǎn)換成其他的直流電壓(1.5V或5.0V),這個(gè)轉(zhuǎn)換器被稱為DC/DC轉(zhuǎn)換器或稱之為開關(guān)電源或開關(guān)調(diào)整器。 DC/DC轉(zhuǎn)換器一般由控制芯片,電感線圈,二極管,三極管,電容器構(gòu)成。 DC/DC轉(zhuǎn)換器為轉(zhuǎn)變輸入電壓后有效輸出固定電壓的電壓轉(zhuǎn)換器。DC/DC轉(zhuǎn)換器分為三類:升壓型DC/DC轉(zhuǎn)換器、降壓型DC/DC轉(zhuǎn)換器以及升降壓型DC/DC轉(zhuǎn)換器。根據(jù)需求可采用三類控制。PWM控制型效率高并具有良好的輸出電壓紋波和噪聲。PFM控制型即使長時(shí)間使用,尤其小負(fù)載時(shí)具有耗電小的優(yōu)點(diǎn)。PWM/PFM轉(zhuǎn)換型小負(fù)載時(shí)實(shí)行PFM控制,且在重負(fù)載時(shí)自動(dòng)轉(zhuǎn)換到PWM控制。目前DC-DC轉(zhuǎn)換器廣泛應(yīng)用于手機(jī)、MP3、數(shù)碼相機(jī)、便攜式媒體播放器等產(chǎn)品中。
標(biāo)簽: DC 轉(zhuǎn)換器
上傳時(shí)間: 2014-12-24
上傳用戶:文993
當(dāng)前,太陽能光伏市場(包括光伏模塊和逆變器)正以每年約30%的年累積速 度增長。太陽能逆變器的作用是將隨太陽能輻射及光照變化的DC 電壓轉(zhuǎn)換成為 電網(wǎng)兼容的AC 輸出;而對(duì)于廣大電子工程師而言,太陽能逆變器是一個(gè)值得高 度關(guān)注的技術(shù)領(lǐng)域。因此下文將介紹太陽能逆變器設(shè)計(jì)所需注意的技術(shù)要點(diǎn)、挑 戰(zhàn)以及相應(yīng)的解決方法。 基本設(shè)計(jì)標(biāo)準(zhǔn) 基于太陽能逆變器的專用性以及保持設(shè)計(jì)的高效率,它需要持續(xù)監(jiān)視太陽能 電池板陣列的電壓和電流,從而了解太陽能電池板陣列的瞬時(shí)輸出功率。它還需 要一個(gè)電流控制的反饋環(huán),用于確保太陽能電池板陣列工作在最大輸出功率點(diǎn), 以應(yīng)付多變的高輸入。目前,太陽能逆變器已有多種拓?fù)浣Y(jié)構(gòu),最常見的是用于 單相的半橋、全橋和Heric(Sunways 專利)逆變器,以及用于三相的六脈沖橋和 中點(diǎn)鉗位(NPC)逆變器;圖1 所示是這些逆變器的拓?fù)鋱D(Microsemi 圖源)。 同時(shí),設(shè)計(jì)還需遵從安全規(guī)范,并在電網(wǎng)發(fā)生故障的時(shí)候可以快速斷開與電網(wǎng)的 連接。因此,太陽能逆變器的基本設(shè)計(jì)標(biāo)準(zhǔn)包括額定電壓、容量、效率、電池能 效、輸出AC 電源質(zhì)量、最大功率點(diǎn)跟蹤(MPPT)效能、通信特性和安全性
標(biāo)簽: 太陽能逆變器
上傳時(shí)間: 2014-12-24
上傳用戶:三人用菜
When a system designer specifies a nonisolated dc/dc powermodule, considering the needed input voltage range isequally as important as considering the required performanceattributes and features. Generally, nonisolated moduleshave either a narrow or a wide input voltage range. Narrowinputmodules typically have a nominal input voltage of3.3, 5, or 12 V. For systems that operate from a tightlyregulated input bus—such as those that do not use batterybackup—a narrow-input module is often adequate sincethe input remains fairly stable.Offering greater flexibility, wide-input modules operatewithin a range of 7 to 36 V, which includes the popular12- or 24-V industrial bus. This enables a single module tobe used for generating multiple voltages. These modulesare ideal for industrial controls, HVAC systems, vehicles,medical instrumentation, and other applications that usea loosely regulated distribution bus. In addition, systemspowered by a rectifier/battery charger with lead-acidbattery backup almost always require wide-input modules.System designers who choose power supplies may wantto take a close look at the latest generation of wide-inputdc/dc modules.
標(biāo)簽: Wide-input modules offer dc
上傳時(shí)間: 2014-12-24
上傳用戶:dragonhaixm
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