Abstract: Electrolytic capacitors are notorious for short lifetimes in high-temperature applications such asLED light bulbs. The careful selection of these devices with proper interpretation of their specifications isessential to ensure that they do not compromise the life of the end product. This application notediscusses this problem with electrolytic capacitors in LED light bulbs and provides an analysis that showshow it is possible to use electrolytics in such products.
上传时间： 2013-11-17
上传用户：asdfasdfd
Linear Technology’s high performance battery management ICsenable long battery life and run time, while providing precision charging control, constantstatus monitoring and stringent battery protection. Our proprietary design techniques seamlesslymanage multiple input sources while providing small solution footprints, faster charging and100% standalone operation. Battery and circuit protection features enable improved thermalperformance and high reliability operation.
上传时间： 2013-10-13
上传用户：yyq123456789
Abstract: Investment in smart meters and smart grid end equipment continues to grow worldwide as countriestry to make their electric delivery systems more efficient. However, as critical as the electric deliveryinfrastructure is, it is normally not secured and thus subject to attack. This article describes the concept oflife-cycle security—the idea that embedded equipment in the smart grid must have security designed into theentire life of the product, even back to the contract manufacturer. We also talk about how life-cycle securityapplies to embedded equipment in the smart grid. Potential threats are discussed, as are potential solutionsto mitigate the risks posed by those threats.
上传时间： 2014-12-24
上传用户：熊少锋
Although recent popular attention is focused on LithiumIon batteries, one must not forget that other batterychemistries, such as Nickel Cadmium (NiCd) and NickelMetal Hydride (NiMH) have advantages in rechargeablepower systems. Nickel-based batteries are robust, capableof high discharge rates, have good cycle life, do notrequire special protection circuitry and are less expensivethan Li-Ion. Among the two, NiMH batteries are rapidlyreplacing NiCd because of their higher capacity (40% to50% more) and the environmental concerns of the toxiccadmium contained in NiCd batteries.
上传时间： 2013-11-04
上传用户：qq10538412
Low power standby requirements are typically associatedwith battery-powered systems. Automotive systems,for example, commonly require power supplies tomaintain output voltage regulation even under no-loadconditions—while drawing minimal quiescent current topreserve battery life. Rising energy costs, however, haveextended the need for low current standby operation toline-powered systems, such as small plugged-in appliancesfor home and business.
上传时间： 2013-11-20
上传用户：xinyuzhiqiwuwu
Alkaline batteries are convenient because they’re easy tofi nd and relatively inexpensive, making them the powersource of choice for portable instruments and devicesused for outdoor recreation. Their long shelf life alsomakes them an excellent choice for emergency equipmentthat may see infrequent use but must be ready to go on amoment’s notice. It is important that the DC/DC convertersin portable devices operate over the widest possiblebattery voltage range to extend battery run time, and thussave the user from frequent battery replacement.
上传时间： 2014-12-24
上传用户：569342831
Industrial remote monitoring systems and keep-alivecircuits spend most of their time in standby mode. Manyof these systems also depend on battery power, so powersupply effi ciency in standby state is very important tomaximize battery life. The LT®8410/-1 high effi ciencyboost converter is ideal for these systems, requiringonly 8.5μA of quiescent current in standby mode. Thedevice integrates high value (12.4M/0.4M) output feedbackresistors, signifi cantly reducing input current whenthe output is in regulation with no load. Other featuresinclude an integrated 40V switch and Schottky diode,output disconnect with current limit, built in soft-start,overvoltage protection and a wide input range, all in atiny 8-pin 2mm × 2mm DFN package.
上传时间： 2013-11-23
上传用户：新手无忧
Notebook and palmtop systems need a multiplicity ofregulated voltages developed from a single battery. Smallsize, light weight, and high efficiency are mandatory forcompetitive solutions in this area. Small increases inefficiency extend battery life, making the final productmuch more usable with no increase in weight. Additionally,high efficiency minimizes the heat sinks needed onthe power regulating components, further reducing systemweight and size.
上传时间： 2013-11-11
上传用户：大三三
For a variety of reasons, it is desirable to charge batteriesas rapidly as possible. At the same time, overchargingmust be limited to prolong battery life. Such limitation ofovercharging depends on factors such as the choice ofcharge termination technique and the use of multi-rate/multi-stage charging schemes. The majority of batterycharger ICs available today lock the user into one fixedcharging regimen, with at best a limited number ofcustomization options to suit a variety of application needsor battery types. The LTC®1325 addresses these shortcomingsby providing the user with all the functionalblocks needed to implement a simple but highly flexiblebattery charger (see Figure 1) which not only addressesthe issue of charging batteries but also those of batteryconditioning and capacity monitoring.
上传时间： 2013-10-19
上传用户：royzhangsz
The design of battery-powered equipment can often bequite challenging. Since few ICs can operate directly fromthe end-of-life voltage from a 2-cell battery (about 1.8V),most systems require a DC/DCconverter. The systemdesigner often has a limited area in which to place the DC/DC converter; associated inductors and capacitors must be
上传时间： 2013-11-23
上传用户：wys0120
