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The LTC3546 is a dual output current mode buck regulatorwith fl exible output current partitioning. Beyondthe advantages normally associated with dual outputregulators (reduced size, cost, EMI and part count, withimproved effi ciency), the LTC3546’s outputs can bepartitioned for either 3A and 1A outputs, or two 2A outputs.This increases its application range and simplifi esmultiple supply rail designs. A confi gurable Burst Mode®clamp for each output sets the current transition levelbetween Burst Mode operation and forced continuousconduction mode to optimize effi ciency over the entireoutput range. An adjustable switching frequency up to4MHz and internal power MOSFET switches allow forsmall and compact footprints.
標(biāo)簽：
460
DN
輸出
優(yōu)化效率
上傳時間：
2013-11-04
上傳用戶：yxgi5
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The LTC®4151 is a high side power monitor that includesa 12-bit ADC for measuring current and voltage, as wellas the voltage on an auxiliary input. Data is read throughthe widely used I2C interface. An unusual feature in thisdevice is its 7V to 80V operating range, allowing it to coverapplications from 12V automotive to 48V telecom.
標(biāo)簽：
452
DN
汽車應(yīng)用
電源監(jiān)視器
上傳時間：
2013-10-29
上傳用戶：集美慧
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The LTC®4155 and LTC4156 are dual multiplexed-inputbattery chargers with PowerPath™ control, featuring I2Cprogrammability and USB On-The-Go for systems suchas tablet PCs and other high power density applications.The LTC4155’s float voltage (VFLOAT) range is optimizedfor Li-Ion batteries, while the LTC4156 is optimized forlithium iron phosphate (LiFePO4)batteries, supportingsystem loads to 4A with up to 3.5A of battery chargecurrent. I2C controls a broad range of functions and USBOn-The-Go functionality is controlled directly from theUSB connector ID pin.
標(biāo)簽：
高電流
便攜式產(chǎn)品
電池充電器
方案
上傳時間：
2013-10-09
上傳用戶：hanhanj
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High voltage buck DC/DC controllers such as the LTC3890(dual output) and LTC3891 (single output) are popular inautomotive applications due to their extremely wide 4V to60V input voltage range, eliminating the need for a snubberand voltage suppression circuitry. These controllersare also well suited for 48V telecom applications whereno galvanic isolation is required.
標(biāo)簽：
自舉偏置
輸入電壓
降壓型控制器
上傳時間：
2013-10-31
上傳用戶：wwwe
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Handheld electronic devices play a key role in our everydaylives. Because dependability is paramount, handhelds arecarefully engineered with lightweight power sources forreliable use under normal conditions. But no amount ofcareful engineering can prevent the mistreatment theywill undergo at the hands of humans. For example, whathappens when a factory worker drops a bar code scanner,causing the battery to pop out? Such events areelectronically unpredictable, and important data storedin volatile memory would be lost without some form ofsafety net—namely a short-term power holdup systemthat stores suffi cient energy to supply standby power untilthe battery can be replaced or the data can be stored inpermanent memory.
標(biāo)簽：
超級電容器
備用電源
手持設(shè)備
上傳時間：
2013-11-05
上傳用戶：coeus
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The voltage range of Linear Technology’s PowerPath® circuitscan be easily extended with just a few components, thusallowing them to meet the needs of virtually all applications.This application note presents solutions for circuits thatmust withstand large negative voltages, a reverse adapterinput for example, and circuits that must withstand largepositive inputs, such as automotive load-dump.
標(biāo)簽：
PowerPath
汽車
工業(yè)應(yīng)用
電路
上傳時間：
2013-10-21
上傳用戶：幾何公差
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Portable, battery-powered operation of electronic apparatushas become increasingly desirable. Medical, remotedata acquisition, power monitoring and other applicationsare good candidates for batteryoperation. In some circumstances,due to space, power or reliability considerations,it is preferable to operate the circuitry from a single 1.5Vcell. Unfortunately, a 1.5V supply eliminates almost alllinear ICs as design candidates. In fact, the LM10 opamp-reference and the LT®1017/LT1018 comparators arethe only IC gain blocks fully specifi ed for 1.5V operation.Further complications are presented by the 600mV dropof silicon transistors and diodes. This limitation consumesa substantial portion of available supply range, makingcircuit design diffi cult. Additionally, any circuit designedfor 1.5V operation mustfunction at end-of-life batteryvoltage, typically 1.3V. (See Box Section, “Componentsfor 1.5V Operation.”)
標(biāo)簽：
Circuitry
Operation
Single
Cell
上傳時間：
2013-10-30
上傳用戶：hz07104032
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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
上傳時間：
2014-12-24
上傳用戶：dragonhaixm
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Analog Inputs and Outputs in an S7 PLC are represented in the PLC as a 16-bit integer. Over
the nominal span of the analog input or output, the value of this integer will range between -
27648 and +27648. However, it is easier to use the analog values if they are scaled to the
same units and ranges as the process being controlled. This applications tip describes
methods for scaling analog values to and from engineering units.
標(biāo)簽：
300
PLC
西門子
模擬量
上傳時間：
2013-11-17
上傳用戶：3294322651
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數(shù)字控制的交流調(diào)速系統(tǒng)所選用的微處理器、功率器件及產(chǎn)生PWM波的方法是影響交流調(diào)速系統(tǒng)性能好壞的直接因素。在介紹了正弦脈寬調(diào)制(SPWM)技術(shù)的基礎(chǔ)上，設(shè)計(jì)了一種以8098單片機(jī)作為控制器，以智能功率模塊IPM為開關(guān)器件的變頻調(diào)速系統(tǒng)。通過軟件編程，產(chǎn)生正弦脈沖寬度調(diào)制波形來控制絕緣柵雙極晶體管的導(dǎo)通和關(guān)斷，從而達(dá)到控制異步電動機(jī)轉(zhuǎn)速的目的。實(shí)驗(yàn)結(jié)果表明，該系統(tǒng)可調(diào)頻率調(diào)電壓，穩(wěn)定度高，調(diào)速范圍寬，具有較強(qiáng)的實(shí)用價(jià)值
Abstract:
AC variable speed with digital control systems used microprocessors， power devices and generate PWM wave is the direct factors of affecting the performance AC speed regulation system. On the basis of introducing the sinusoidal pulse width modulation (SPWM) technology，this paper designed variable speed system which used 8098 as a controller， intelligent power module IPM as switching device. Through software programming， resulting in sinusoidal pulse width modulation waveform to control the insulated gate bipolar transistor turn on and off， so as to achieve the purpose of speed control of induction motors. Experimental results show that the system can adjust frequency modulation voltage， high stability， wide speed range， has a strong practical value.
標(biāo)簽：
8098
SPWM
單片機(jī)
變頻調(diào)速系統(tǒng)
上傳時間：
2013-11-14
上傳用戶：ynwbosss
