LTC3108



3108fa

Typical applicaTion

DescripTion

Ultralow Voltage Step-Up

Converter and Power Manager

forharvestingandmanagingsurplusenergyfromextremely

low input voltage sources such as TEGs (thermoelectric

generators),thermopilesandsmallsolarcells.Thestep-up

topology operates from input voltages as low as 20mV.

The LTC3108 is functionally equivalent to the LTC3108-1

Usingasmallstep-uptransformer,theLTC3108providesa

completepowermanagementsolutionforwirelesssensing

and data acquisition. The 2.2V LDO powers an external

microprocessor, while the main output is programmed to

one of four fixed voltages to power a wireless transmitter

orsensors.Thepowergoodindicatorsignalsthatthemain

output voltage is within regulation. A second output can be

enabled by the host. A storage capacitor provides power

when the input voltage source is unavailable. Extremely

low quiescent current and high efficiency design ensure

the fastest possible charge times of the output reservoir

capacitor.

The LTC3108 is available in a small, thermally enhanced

12-lead (3mm

× 4mm) DFN package and a 16-lead SSOP

package.

Wireless Remote Sensor Application Powered From a Peltier Cell

FeaTures

applicaTions

n

Operates from Inputs of 20mV

n

Complete Energy Harvesting Power

Management System

- LDO: 2.2V at 3mA

- Logic Controlled Output

- Reserve Energy Output

n

Power Good Indicator

n

Uses Compact Step-Up Transformers

n

Small 12-Lead (3mm

× 4mm) DFN or 16-Lead

SSOP Packages

n

Remote Sensors and Radio Power

n

Surplus Heat Energy Harvesting

n

HVAC Systems

n

Industrial Wireless Sensing

n

Automatic Metering

n

Building Automation

n

Predictive Maintenance

3108 TA01a

C1

20mV TO 500mV

C2

SW

VS2

VS1

PGOOD

2.2V

470µF

PGD

VLDO

VSTORE

+

LTC3108

VAUX

GND

0.1F

6.3V

5V

3.3V

1µF

1nF

220µF

1:100

330pF

SENSORS

RF LINK

µP

2.2µF

+

+

+

THERMOELECTRIC

GENERATOR

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.

10

1

100

1000

0

3108 TA01b

0

100 150

250

50

200

300 350 400

1:100 Ratio

1:50 Ratio

1:20 Ratio