LTC3108

1

3108p

TYPICAL APPLICATION

DESCRIPTION

Ultralow Voltage Step-Up

Converter and Power Manager

for harvesting and managing surplus energy from extremely

low input voltage sources such as TEG (thermoelectric

generators), thermopiles and small solar cells. The step-up

topology operates from input voltages as low as 20mV.

Using a small step-up transformer, the LTC3108 provides a

complete power management solution for wireless sensing

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

or sensors. The power good indicator signals that the main

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 (4mm

× 3mm) 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

n

Uses Compact Step-Up Transformers

n

Small 12-Lead (4mm

× 3mm) DFN or 16-Lead

SSOP Packages

n

Remote Sensors and Radio Power

n

Surplus Heat Energy Harvesting

n

HVAC

n

Industrial Wireless Sensing

n

Automatic Metering

n

Building Automation

n

Indoor Light Energy Harvesting

3108 TA01a

C1

TEG

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

+

+

+

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

Electrical Specifications Subject to Change