DESCRIPTION

Demonstration Circuit 1582B featuring the LTC3108 is

a highly integrated DC/DC converter optimized for

harvesting and managing energy from extremely low

input voltage sources such as thermoelectric generators (TEG). The step-up topology operates from input

voltages as low as 20mV.

The DC 1582B Demonstration Circuit has been optimized

for low start-up voltage with a 100:1 turns ratio transformer. For application where it is desirable to trade-off

a higher start-up voltage for higher current, a lower turns

ratio transformer can be used. Refer to the LTC3108

datasheet for more information.

The LTC3108 is designed to accumulate and manage

energy over a long period of time to enable short bursts

of power to be used to acquire and transmit data. The

burst must occur at a low enough duty cycle such that

the total output energy during the burst does not exceed

the average source power integrated over the accumulation time between bursts.

The Demonstration Circuit has been set up with a storage

capacitor that makes it easy to evaluate the general functionality of the circuit. The lower value capacitor allows

for a fast charge time but limits the pulsed energy that

can be drawn from it. Space is provided, and alternate

part footprints have been built into the PCB to allow experimentation with larger capacitors for more energy

storage. In a typical application, the larger output capacitors may be used. Refer to the datasheet for more information including equations to properly size the output

capacitors for a given application.

The LTC3108 is available in two versions, the only difference being the VOUT and VOUT2 output voltages. Refer

to the datasheets for more information.

Design files for this circuit board are available. Call

the LTC factory.