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.
上傳時間： 2013-10-17
上傳用戶：xjz632
Linear Technology offers a variety of devices that simplifyconverting power from a USB cable, but the LTC®3455represents the highest level of functional integration yet. The LTC3455 seamlessly manages power flowbetween an AC adapter, USB cable and Li-ion battery,while complying with USB power standards, all from a4mm × 4mm QFN package. In addtion, two high efficiencysynchronous buck converters generate low voltage railswhich most USB-powered peripherals require. TheLTC3455 also provides power-on reset signals for themicroprocessor, a Hot SwapTM output for poweringmemory cards as well as an uncommitted gain blocksuitable for use as a low-battery comparator or an LDOcontroller. The PCB real estate required for the entire USBpower control circuit and two DC/DC converters is only225mm2.
上傳時間： 2013-11-02
上傳用戶：名爵少年
The MAX14885E, a 2:2 VGA switch, connects a VGA source to a VGA monitor. To ease direct connection to graphics controllers orthe ASIC, the MAX14885E has two supplies: VCC, a 5V ±5% supply, drives the VGA side interface; and the VL supply sets the logicswitching thresholds on the digital input pins (EN, S00, S01, S10, S11, SHA, SHB, SVA, and SVB). This application note documentsthe proper sequencing of the VCC and VL power supplies on power-up.
上傳時間： 2013-10-23
上傳用戶：wuchunzhong
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.
上傳時間： 2013-11-04
上傳用戶：qq10538412
Traditionally, an Electronic Circuit Breaker (ECB) comprisesa MOSFET, a MOSFET controller and a current senseresistor. The LTC®4213 does away with the sense resistorby using the RDS(ON) of the external MOSFET. The resultis a simple, small solution that offers a signifi cant lowinsertion loss advantage at low operating load voltage.The LTC4213 features two circuit breaking responses tovarying overload conditions with three selectable tripthresholds and a high side drive for an external N-channelMOSFET switch.
上傳時間： 2014-03-02
上傳用戶：lixinxiang
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.
上傳時間： 2013-10-11
上傳用戶：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.
上傳時間： 2013-10-09
上傳用戶：Jerry_Chow
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.
上傳時間： 2013-11-04
上傳用戶：yxgi5
Today’s computer, datacom, and telecom systems demandpower supplies that are effi cient, respond quicklyto load transients and accurately regulate the voltageat the load. For example, load current can be measuredby using the inductor DCR, thus eliminating the needfor a dedicated sense resistor. Inductor DCR sensingincreases effi ciency—especially at heavy load—whilereducing component cost and required board space.The LTC®3856 single-output 2-phase synchronous buckcontroller improves the accuracy of inductor DCR sensingby compensating for changes in DCR due to temperature.
上傳時間： 2013-11-05
上傳用戶：guobing703
In general, a Hot Swap controller provides two importantfunctions to boards that can be plugged and unpluggedfrom a live backplane:
上傳時間： 2013-10-23
上傳用戶：行者Xin
