LTC3105, a high
performance, synchronous boost converter incorporates maximum power point
control (MPPC) and starts up with inputs as low as 250mV. The LTC3105 operates
over an input range of 0.2 to 5V, making it useful for harvesting energy from
high impedance alternative power sources, including photovoltaic cells,
thermoelectric generators (TEGs) and fuel cells. The LTC3105's internal 400mA
synchronous switches maximize efficiency while its Burst Mode¬ģ
operation offers quiescent current of only 22uA, further optimizing converter
efficiency overall operating conditions. A user-programmable MPPC set point
maximizes the energy that can be extracted from any power source without
collapsing its internal voltage.
The LTC3105 is useful to power wireless sensors and data acquisition
applications. Surplus or ambient energy can be harvested and then used to
generate system power in lieu of traditional wired or battery power, which may
be expensive or impractical. Typically, these applications require very low
average power, but require periodic pulses of higher load current. For example,
the LTC3105 can be used in wireless sensor applications where the power load is
extremely low when the sensor is in standby mode, interrupted by periodic high
load bursts, when the circuitry is powered up to take measurements and transmit
offers an auxiliary LDO that delivers up to 6mA of output current to
power external microcontrollers and sensors while the main output is charging.
Once fully charged, the main output can deliver voltages as high as 5.25V with
up to 100mA of output current. It can also regulate VOUT even when VIN
is greater than or equal to VOUT
, offering further design
flexibility. In shutdown, the LTC3105 offers output disconnect, isolating VIN
, requiring only 4uA of quiescent current.
is available in a 10-lead 3 x 3mm DFN package and the LTC3105EMS is
available in an MSOP-12 package. Prices start at $2.70 each for 1,000-piece
quantities. Both are available from stock.