Linear Technology

Linear Tech Announces Wide Input Voltage Range Step-Down DC-DC Controller

七月 27, 2011
By

July 21, 2011

Linear Tech
Announces Wide Input Voltage Range Step-Down DC-DC Controller

http://www.powerpulse.net/story.php?src=r1;storyID=24336

Power Channels: Power Components, Switch-Mode Power

Linear Technology Corp. announced the H- and MP- grade versions of the LTC3851A, a wide input voltage range (4 to 38V) synchronous step-down dc-dc controller that encompasses a broad range of applications, including most intermediate bus voltages and battery chemistries. The strong onboard MOSFET gate drivers enable the use of high power external MOSFETs to produce output currents up to 25A with output voltages ranging from 0.8 to 5.5V, well suited for point-of-load requirements. These H- and MP-grade versions are tested and guaranteed to operating junction temperature ranges from -40 to 150°C and -55 to 150°C, respectively. Applications include automotive systems, industrial, medical, datacom and telecom.

A constant-frequency, current-mode architecture allows a selectable fixed or phase-locked loop (PLL) frequency from 250 to 750kHz . Output current sensing is accomplished by measuring the voltage drop across the output inductor (DCR) or using an optional sense resistor. Current foldback limits MOSFET heat dissipation during short circuit and overload conditions. Selectable continuous, pulse skipping or Burst Mode® operation is user controlled to optimize light load efficiency. With up to 99% duty cycle, the LTC3851A/-1 has a very low dropout voltage, a useful feature for extending run times in battery powered applications. Additional features include tracking and adjustable soft-start. The LTC3851A-1 differs from the LTC3851A in that it has a power good signal instead of adjustable current limit.

The LTC3851AH/-1 and LTC3851AMP/-1 are available in a thermally enhanced MSOP-16 package.

The 1000-piece price starts at $2.24 each for the H-grade devices and $5.29 each for the MP-grade parts, respectively.

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Arrow Electronics Offers Turnkey Energy-Harvesting Reference Design

六月 20, 2011
By

Arrow Electronics Offers

Turnkey Energy-Harvesting Reference Design

http://eon.businesswire.com/news/eon/20110616006103/en/Arrow-Electronics-Offers-Turnkey-Energy-Harvesting-Reference-Design

Teams with industry-leading suppliers to provide comprehensive, self-sustaining, ultra-low-power wireless sensor network solution

June 16, 2011 10:24 AM Eastern Daylight Time 

MELVILLE, N.Y.–(EON: Enhanced Online News)–Arrow Electronics, Inc. has joined with leading suppliers Silicon Labs, Infinite Power Solutions and Linear Technology Corporation to launch a turnkey energy-harvesting reference design enabling wireless networks powered by a solar energy-harvesting source.

“Working together with industry leaders Silicon Labs, Infinite Power Solutions and Linear Technology, we’ve developed a complete solution that can help customers reduce the complexity and enhance the sustainability of a variety of wireless networking applications”

The energy-harvesting reference design offers a simple, cost-effective bill of materials based on several key components. The design includes a solar-powered wireless sensor node that measures temperature, light level and charge level. It uses Silicon Labs’ ultra-low-power Si10xx wireless microcontroller (MCU) to control the sensor system and transmit data wirelessly. It also incorporates a thin-film battery to store harvested energy, as well as a battery charger IC for efficient power management. The data is transmitted to a wireless USB adapter included with the reference design that connects the wireless sensor node to a PC where sensor data for up to four nodes is displayed via an easy-to-use network GUI.

“Working together with industry leaders Silicon Labs, Infinite Power Solutions and Linear Technology, we’ve developed a complete solution that can help customers reduce the complexity and enhance the sustainability of a variety of wireless networking applications,” said David West, vice president of supplier marketing and asset for Arrow Electronics.

Silicon Labs’ Si10xx wireless MCUs offer very low active current of 160 µA/MHz and very low sleep mode current, as low as 25 nA, to conserve system resources. The Si10xx MCUs can also wake up very quickly in 2 µS. An on-chip wireless transceiver enables 20 dBm output power and RF sensitivity of -121 dBm, greatly increasing the wireless range. An integrated dc-dc switching regulator enables a wide input voltage range of 0.9V to 3.6V, which is particularly useful in energy-harvesting applications where outputs typically vary.

The reference design uses a THINERGY® solid-state, rechargeable, micro-energy cell (MEC), a unique type of thin film battery, with a capacity of 0.7 mAh developed by Infinite Power Solutions. In direct sunlight, the battery can be recharged fully in only one hour. While in sleep mode, the wireless sensor node will retain a charge for 7,000 hours. If the wireless system is transmitting continuously, it will operate non-stop for about three hours, although it is designed to constantly recharge itself at an appropriate level to keep the MEC from completely discharging.

Linear’s LTC4071 battery charger IC provides additional power management and offers an easy-to-use shunt battery system for Li-ion/Polymer batteries that integrates a charger and battery pack protection into one IC.

The LTC4071, with its 550 nA operating current, charges and protects batteries from previously unusable very low current, intermittent or continuous charging sources.

The LTC4071 can charge at currents up to 50 mA. A near zero (0.1 nA ) low-battery-latching disconnect function protects even low-capacity batteries from deep discharge and potentially irreparable damage. With pin-selectable settings of 4.0 V, 4.1 V or 4.2V, the LTC4071 IC’s 1 percent accurate battery float voltage allows the developer to optimize the balance between battery capacity and lifetime.

Silicon Labs’ wireless sensor energy-harvesting reference design accommodates a wide range of harvested energy sources. An on-board bypass connector gives developers the flexibility to tap other energy-harvesting sources such as vibration, thermal and RF.

To register for a free kit, visit www.arrownac.com/charge. To learn more, e-mail energysolutions@arrow.com.

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Energy Harvesting LTC3105

五月 10, 2011
By

 

The LTC3105 is a

LTC3105 – 400mA Step-Up DC/DC Converter with Maximum Power Point Control and 250mV Start-Up

high efficiency step-up DC/DC converter that can operate from input voltages as low as 225mV.

A 250mV start-up capability and integrated maximum power point controller (MPPC) enable operation directly from low voltage, high impedance alternative power sources such as photovoltaic cells, TEGs (thermoelectric generators) and fuel cells.

A user programmable MPPC set point maximizes the energy that can be extracted from any power source.

Burst Mode operation, with a proprietary self adjusting peak current, optimizes converter efficiency and output voltage ripple over all operating conditions.

The AUX powered 6mA LDO provides a regulated rail for external microcontrollers and sensors while the main output is charging. In shutdown, IQ is reduced to 10μA and integrated thermal shutdown offers protection from overtemperature faults. The LTC3105 is offered in 10-lead 3mm × 3mm × 0.75mm DFN and 12-lead MSOP packages.

http://www.linear.com/product/LTC3105?utm_source=3105&utm_medium=bnr&utm_campaign=PMDL

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Multicell Battery Stack Monitor IC for High Voltage Applications

四月 10, 2011
By

 

Multicell Battery Stack Monitor IC

for High Voltage Applications

http://www.eetimes.com/electronics-products/electronic-product-reviews/processors/4214731/Analog-front-end-MCU-eases-anti-tampering-in-meter-design?cid=NL_EETimesDaily

Stacks of lithium ion cells are used in new hybrid electric vehicles and uninterruptible power supplies.

Maximizing the life and the safety of these high voltage, high power battery packs depends on sophisticated electronics.

Linear Technology’s LTC®6803 Multicell Battery Stack Monitor is the key component in a battery management system.

The precision, noise immunity, low current modes, and built in diagnostics of the LTC6803 are critical to maintaining the proper state of charge and state of health of every cell.

The unique stacking architecture reduces system cost by eliminating isolation components. Comprehensive applications support helps customers quickly integrate the LTC6803 into their products.

http://video.eetimes.com/playlist/video-design-ideas/594990914001

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Flyback regulator simplifies design, eliminates optocoupler

三月 4, 2011
By

Flyback regulator simplifies design, eliminates optocoupler

http://www.eetimes.com/electronics-products/power-products/4213496/Flyback-regulator-simplifies-design–eliminates-optocoupler?cid=NL_Automotive

2/24/2011 8:31 AM EST

Linear Technology Corp. announced the LT3512, a high voltage isolated monolithic flyback regulator that simplifies the design of an isolated DC/DC converter.

No optocoupler, third winding or signal transformer is required for feedback since the output voltage is sensed from the primary-side flyback signal. The LT3512 operates over a 4.5V to 100V input voltage range, has a 420mA, 150V power switch and delivers up to 4.5 watts of output power, making it well suited for a wide variety of telecom, datacom, automotive, industrial and medical applications.

Key highlights:

  • VIN Range from 4.5V to 100V
  • Onboard 420mA, 150V Integrated Power Switch
  • No Optocoupler, Transformer or Third Winding Required for Feedback
  • Current-Mode Control
  • Boundary-Mode Operation
  • VOUT Set with Two External Resistors
  • Off-the-Shelf Transformers
  • Programmable Undervoltage Lockout
  • Output Voltage Temperature Compensation
  • Small MSOP-16 package

Pricing: Starts at $3.15 each in 1000-piece quantities.

Availability: In addition to the extended and industrial versions that operate over a junction temperature range from -40°C to 125°C, a high temperature automotive grade is available that operates from -40°C to 150°C. 

Datasheet: Click here.

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LTC6801 – Independent Multicell Battery Stack Fault Monitor

二月 21, 2011
By

LTC6801

– Independent Multicell Battery Stack Fault Monitor

FEATURES
  • Monitors Up to 12 Li-Ion Cells in Series
    (60V Max)
  • Stackable Architecture Enables > 1000V Systems
  • 1% Maximum Overvoltage Detection Level Error
  • Adjustable Overvoltage and Undervoltage Detection
  • Self Test Features Guarantee Accuracy
  • Robust Fault Detection Using Differential Signals
  • Simple Pin-Strapped Confi guration Allows Battery Monitoring without a Microcontroller
  • 15.5ms to Monitor All Cells in a System
  • Programmable Response Time
  • Two Temperature Monitor Inputs
  • Low Power Idle Mode
  • 36-Lead SSOP Package
TYPICAL APPLICATION

LTC6801 Typical Application

 

DESCRIPTION

The LTC6801 is a multicell battery monitoring IC incorporating a 12-bit ADC, a precision voltage reference, sampled comparator, and a high voltage input multiplexer. The LTC6801 can monitor as many as 12 series connected battery cells for overvoltage, undervoltage, and overtemperature conditions, indicating whether the cells are within specified parameters. The LTC6801 generates a clock output when no fault conditions exist. Differential clocking provides high noise immunity and ensures that battery stack fault conditions cannot be hidden by frozen bits or short circuit conditions.

Each LTC6801 can operate with a battery stack voltage up to 60V and multiple LTC6801 devices can be stacked to monitor each individual cell in a long battery string. When multiple devices are stacked, the status signal of each LTC6801 can be daisy-chained, without opto-couplers or isolators, providing a single status output for the entire battery string.

The LTC6801 is configurable by external pin strapping. Adjustable overvoltage and undervoltage thresholds support various Li-Ion chemistries. Selectable measurement times allow users to save power.

http://www.linear.com/product/LTC6801?utm_source=6801&utm_medium=bnr&utm_campaign=ACDL

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60V降壓轉換器可驅動3組10顆100mA LED-LTC

十月 3, 2010
By

 

60V降壓轉換器可驅動3組10顆100mA LED

凌力爾特(Linear Technology)日前發表 60V、1MHz 降壓DC/DC轉換器LT3596，其專門設計以操作為驅動30顆LED之定電流LED驅動器。

LT3596 可從48V輸入驅動3組分別達10顆100mA串聯之LED，效率可達90%。

多通道能力使其成為LED 告示板及工業與醫療顯示器應用的理想選擇，

而6V至60V輸入電壓範圍，則使其適用於汽車和工業應用。

LT3596可提供+ 1.5% 的 LED電流匹配以確保顯示器的一致性亮度，高達10,000:1的調光比可透過True Color PWM 調光來達成。可設定的200kHz至1MHz定頻操作，以及電流模式架構，使其能於廣泛的供應和輸出電壓範圍內達到穩定操作，同時可將外部零組件尺寸縮減至最小，切換頻率並可與外部時脈同步化。LT3596的散熱加強型5mm x 8mm QFN封裝，為LED背光應用提供一個非常精小的layout面積。

LT3596透過單一800mA、60V內部開關來提供降壓固定電流源。內部降壓轉換器使用自適性回授迴路以穩壓輸出電壓，使其稍高於所需的LED電壓以確保最大效率， 如果其中任一串LED遭遇開路或短路，LT3596將持續穩壓既有的LED串，並警示FAULT針腳訊號。其它功能包括依據接面溫度及/或LED溫度而定的LED電流降額，以及關機時的LED斷開。

LT3596EUHG供貨39接腳5mm x 8mm QFN 封裝。

工業等級版本之LT3596IUHG 業經測試，並保證操作於-40℃ 至125℃操作接面溫度。所有版本均已供貨。

 

http://www.eettaiwan.com/ART_8800612213_617739_NP_e44bb7c4.HTM?click_from=8800061005,8723946550,2010-09-28,EETOL,NEWSLETTER

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