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
Many telecommunications and computing applicationsneed high effi ciency step-down DC/DC converters thatcan operate from a very low input voltage. The highoutput power synchronous controller LT3740 is idealfor these applications, converting input supplies rangingfrom 2.2V to 22V to outputs as low as 0.8V with loadcurrents from 2A to 20A. Applications include distributedpower systems, point-of-load regulation and conversionof logic supplies.
上传时间: 2013-11-05
上传用户:zhf01y
The LTC®3562 quad output step-down regulator is designedfor multicore handheld microprocessor applications thatoperate from a single Li-Ion battery. Its four monolithic, higheffi ciency buck regulators support Intel’s mobile CPU P-Stateand C-State energy saving operating modes. The outputvoltages are independently controllable via I2C, and eachoutput can be independently started and shut down. Designerscan choose from power saving pulse-skipping mode orBurst Mode® operation, or select low noise LDO mode. Thespace-saving LTC3562 is available in a 3mm × 3mm QFNpackage and requires few external components.
上传时间: 2013-10-07
上传用户:1583060504
Handheld designers often grapple with ways to de-bounceand control the on/off pushbutton of portable devices.Traditional de-bounce designs use discrete logic, fl ipflops, resistors and capacitors. Other designs includean onboard microprocessor and discrete comparatorswhich continuously consume battery power. For highvoltage multicell battery applications, a high voltageLDO is needed to drive the low voltage devices. All thisextra circuitry not only increases required board spaceand design complexity, but also drains the battery whenthe handheld device is turned off. Linear Technology addressesthis pushbutton interface challenge with a pairof tiny pushbutton controllers.
上传时间: 2013-11-18
上传用户:ZJX5201314
The makers of handheld medical, industrial and consumerdevices use a wide variety of high resolution, small tomedium sized color TFT LCD displays. The power supplydesigners for these displays must contend with shrinkingboard area, tight schedules, and variations in displaytypes and feature requirements. The LTC®3524 simplifi esthe designer’s job by combining a versatile, easily programmed,TFT LCD bias supply and white LED backlightdriver in a low profi le 4mm × 4mm QFN package.
上传时间: 2013-10-26
上传用户:chens000
Piezoelectric motors are used in digital cameras for autofocus,zooming and optical image stabilization. Theyare relatively small, lightweight and effi cient, but theyalso require a complicated driving scheme. Traditionally,this challenge has been met with the use ofseparatecircuits, including a step-up converter and an oversizedgeneric full-bridge drive IC. The resulting high componentcount and large board space are especially problematicin the design of cameras for ever shrinking cell phones.The LT®3572 solves these problems by combining astep-up regulator and a dual full-bridge driver in a 4mm× 4mm QFN package. Figure 1 shows a typical LT3572Piezo motor drive circuit. A step-up converter is usedto generate 30V from a low voltage power source suchas a Li-Ion battery or any input power source within thepart’s wide input voltage range of 2.7V to 10V. The highoutput voltage of the step-up converter, adjustable upto 40V, is available for the drivers at the VOUT pin. Thedrivers operate in a full-bridge fashion, where the OUTAand OUTB pins are the same polarity as the PWMA andPWMB pins, respectively, and the OUTA and OUTB pinsare inverted from PWMA and PWMB, respectively. Thestep-up converter and both Piezo drivers have their ownshutdown control. Figure 2 shows a typical layout
上传时间: 2013-11-18
上传用户:hulee
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
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
Avalanche photo diode (APD) receiver modules arewidely used in fi ber optic communication systems. AnAPD module contains the APD and a signal conditioningamplifi er, but is not completely self contained. It stillrequires signifi cant support circuitry including a highvoltage, low noise power supply and a precision currentmonitor to indicate the signal strength. The challenge issqueezing this support circuitry into applications withlimited board space. The LT®3482 addresses this challengeby integrating a monolithic DC/DC step-up converter andan accurate current monitor. The LT3482 can supportup to a 90V APD bias voltage, and the current monitorprovides better than 10% accuracy over four decades ofdynamic range (250nA to 2.5mA).
上传时间: 2014-01-18
上传用户:wenyuoo
Automotive power systems are unforgiving electronicenvironments. Transients to 90V can occur when thenominal voltage range is 10V to 15V (ISO7637), along withbattery reversal in some cases. It’s fairly straightforwardto build automotive electronics around this system, butincreasingly end users want to operate portable electronics,such as GPS systems or music/video players,and to charge their Li-Ion batteries from the automotivebattery. To do so requires a compact, robust, effi cientand easy-to-design charging system
上传时间: 2013-11-04
上传用户:wfl_yy