ltc3108 presentation

8/8/2019 LTC3108 Presentation

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2005 Linear Technology

Linear TechnologyCorporation

Tony ArmstrongDirector of Product Marketing - Power Products

2009Linear Technology

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Energy Harvesting - Opportunity

Charge, supplement or replace batteries in systems where batteryuse is inconvenient, impractical, expensive or dangerous

Eliminate the need for wires to carry power or to transmit data

Smart wireless sensor networks to monitor and optimize complexindustrial processes, remote field installations and building HVAC

Harvesting otherwise wasted heat from industrial processes, solarpanels, internal combustion engines, etc.

Various consumer electronic accessory chargers


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Energy Harvesting Sources

Thermo-Electric Generator or Thermopile (Heat)

Piezo-Electric (Vibration or strain)

PhotoVoltaic (Light)

Galvanic (Moisture)

Coil/Magnet (Motion)


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LTC3108: Ultra-Low Voltage (20mV) Step-Up converter and Power Manager

Operates from inputs aslow as 20mV

Selectable Fixed OutputVoltages

Unique Resonant Powerconverter / EnergyHarvester

Auxiliary LDO Manages Energy storage

between Reservoir and MainCout or Batt

Compact Step-up X-former

3x4mm DFN or GN16packages

Design: Dave Salerno

Transformer: Coilcraft LPR-6235


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LTC3108: Energy Harvesting Applications

Remote Industrial Sensor networks

HVAC monitoring and control

Building Automation

Predict ive Maintenance

Avionics

Automatic Metering

Free

Energy

Source

Energy

Harvester /

Manager

Sensors,

A/D,

UController

Wireless

transmitter /

receiver

TEG, PV, Piezo,

Electrochemical,

trees

LTC3108

Power Conversion and

Energy Management is

the Missing Link


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LTC3108 Block Diagram Review

VOUT: Main Output

Charge Control and Prioritizer

VSTORE: Energy Reservoir

VOUT2: Switched VOUT

Digital Vout Select

3mA LDO: uControllerpower

Rectifier

Compact Step-Up transformer

20mV Vin Source

VAUX: Intermediate Charge storage andIC bias supply

Depletion ModeMOSFET


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LTC3108 Feature: 20mV Resonant Boost Topology

20m V Operation or ~1deg dT if powered from a PeltierEffect Thermal Electric Generator (TEG or TEC)

LTC proprietary compound Depletion mode N-ChannelMOSFET makes extreme low voltage possible

Circuit Self-oscillates, resonant circuit formed by Lmag andCg

Built-in Synchronous rectification improves Energyharvesting yield

1 :100 transformer i sstandard Coilcraft part (LPR-6235),6mm x 6mm x 3.5mm


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LTC3108: Typical Performance

Key Points:

Average Power for the App, must be 10s of mWs or less

Higher Sample Rates = Higher dT or betterTEG required

Best Performance is obtained with lowest Rs TECs/TEGs

LTC3108: Typical Performance Data


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LTC3108: More Typical Performance Data

Key Points:

Bigger Area TEG = More mV per delta T, bu t also more ESR

Small dT Use 1:100 transformer

Large dT Use 1:50 or 1:20 or lower turns ratio transformers


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LTC3108: TEG / TEG Reference Data

Remember: Bigger TEG doesnt always mean more available power!


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LTC3108: Indoor Light Powered PhotoVoltaic Charger

~200 to 300mV available fromsmall Solar Cells with Indoorlighting

Battery or Storage Capacitor onoutput is trickle charged

1:20 transformer maximizes powerdelivery (charging current)

Potential Applications:

Autonomous Proximity Sensors

Battery-less Smoke/Gas detectors


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LTC3108: Demo Circuit DC1582A

Rev.B will use the 3x4mm DFN package.


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LTC3108: Schedule

Datasheet: Now

First Samples: Now

Demo Boards: Now

Product Release Date: December 1, 2009

ltc3108 presentation

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