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.