Fran Granville
Linear Technology recently introduce the LTC3588-1 energy harvester, targeting low-energy sources, including piezoelectric transducers. The LTC3588-1 integrates a low-loss, full-wave bridge rectifier with a high-efficiency buck converter to harvest ambient vibrational energy through piezoelectric transducers and then convert it to a well-regulated output to power application microcontrollers, sensors, data converters, and wireless transmission components.
The LTC3588-1 operates from an input-voltage range of 2.7 to 20V, making it suitable for a wide array of piezoelectric transducers, as well other high-output-impedance energy sources. Its buck dc/dc converter delivers as much as 100 mA of continuous output current or even higher pulsed loads. You can program its output to one of four fixed voltages of 1.8, 2.5, 3.3, or 3.6V to power a wireless transmitter or sensor. Quiescent current is 950 nA with the output in regulation at no load, maximizing overall efficiency.
The LTC3588-1 interfaces directly with a piezoelectric or alternative ac-power source, rectifies a voltage waveform, stores harvested energy in an external storage capacitor, and dissipates any excess power through an internal shunt regulator. A quiescent current of 450 nA and an undervoltage-lockout mode with a wide hysteresis window enable charge to accumulate on the storage capacitor until the buck converter can efficiently transfer a portion of the stored charge to the output. In its no-load sleep state, the LTC3588-1 regulates the output voltage, consuming only 950 nA of quiescent current while continuously charging the storage capacitor. The LTC3588-1 requires minimal external components and comes in a 3×3-mm DFN or a thermally enhanced MSOP-10 package.
The LTC3588EDD-1 is available in a 3×3-mm DFN package, and the LTC3588EMSE-1 is available in a thermally enhanced MSOP-10 package. Prices start at $2.95 (1000). Industrial-temperature-grade versions, the LTC3588IDD-1 and LTC3588IMSE-1, are also available, with prices starting at $3.47 (1000).
