The CN3052A is a complete constant-current /constant voltage linear charger for single cell Li-ion and Li Polymer rechargeable batteries. The device contains an on-chip power MOSFET and eliminates the need for the external sense resistor and blocking diode.
上传时间: 2013-11-10
上传用户:子虚乌有
In this paper, two types of MMIC voltage controlled oscillators have been successfully demonstrated. The first chip with single tuning diode shows the excellent tuning linearity. The second chip with two tuning diodes can improve the tuning bandwidth.
上传时间: 2013-10-17
上传用户:xjz632
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
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.
上传时间: 2013-11-21
上传用户:aix008
Typical industrial and automotive applications requiremultiple high current, low voltage power supply solutionsto drive everything from disc drives to microprocessors.For many of these applications, particularly thosethat have size constraints, the LT3501® dual step-downconverter is an attractive solution because it’s compactand inexpensive compared to a 2-chip solution. The dualconverter accommodates a 3V to 25V input voltage rangeand is capable of supplying up to 3A per channel. Thecircuit in Figure 1 produces 3.3V and 1.8V.
上传时间: 2014-12-24
上传用户:372825274
The LTC®3569 is a compact power solution for handhelddevices. Its tiny 3mm × 3mm QFN package includesthree buck regulators with individually programmableoutput voltages. One regulator supports load currentsup to 1200mA, while the other two support currents to600mA. Two regulators can be paralleled for increasedload capability. Each current-mode regulator is internallycompensated with excellent load and line regulation. Acomplete 2- or 3-output solution requires a minimumof external passive components.
上传时间: 2013-10-11
上传用户:yxgi5
Many system designers need an easy way to producea negative 3.3V power supply. In systems that alreadyhave a transformer, one option is to swap out the existingtransformer with one that has an additional secondarywinding. The problem with this solution is that manysystems now use transformers that are standard, offthe-shelf components, and most designers want toavoid replacing a standard, qualifi ed transformer with acustom version. An easier alternative is to produce thelow negative voltage rail by stepping down an existingnegative rail. For example, if the system already employsan off-the-shelf transformer with two secondary windingsto produce ±12V, and a –3.3V rail is needed, a negativebuck converter can produce the –3.3V output from the–12V rail.
上传时间: 2013-10-09
上传用户:Jerry_Chow
One of the fi rst lessons in a basic electronics coursecovers the symbols for resistors, capacitors, inductors,voltage sources and current sources. Althougheach symbol represents a functional component of areal-world circuit, only some of the symbols have directphysical counterparts. For instance, the three discretepassive devices—resistors, capacitors, inductors—canbe picked off a shelf and placed on a real board muchas their symbolic analogs appear in a basic schematic.Likewise, while voltage sources have no direct 2-terminalanalog, a voltage source can be easily built with an offthe-shelf linear regulator.
上传时间: 2013-11-24
上传用户:simonpeng
What would happen if someone connected 24V to your12V circuits? If the power and ground lines were inadvertentlyreversed, would the circuits survive? Does yourapplication reside in a harsh environment, where the inputsupply can ring very high or even below ground? Evenif these events are unlikely, it only takes one to destroya circuit board.
上传时间: 2013-10-26
上传用户:jackandlee
Specifying the right reference and applying it correctly isa more difficult task than one might first surmise, consideringthat references are only 2- or 3-terminal devices.Although the word “accuracy” is most often spoken inreference to references, it is dangerous to use this wordtoo freely because it can mean different things to differentpeople. Even more perplexing is the fact that a referenceclassified as a dog in one application is a panacea inanother. This application note will familiarize the readerwith the various aspects of reference “accuracy” andpresent some tips on extracting maximum performancefrom any reference.
标签: 电压基准
上传时间: 2013-10-15
上传用户:liuwei6419