EnerPak from TPL Inc is a sophisticated power management and energy storage system for energy harvesting-powered wireless sensors that have moderate power needs due to high data rate, the need to support a mesh network topology, or complex data measurement requirements. It features dynamic peak power tracking, a broad operating temperature range (-20°C to 60°C), and a broad dynamic range of delivered power (from microWatts to hundreds of milliWatts). It accommodates the low, variable and intermittent nature of energy harvesting sources, while providing reliable, regulated power necessary for critical sensing applications. Built around an ultra-low power microcontroller, EnerPak can consume as little as 5-8µA, enabling efficient use of the harvested energy for the application load. The system uses low impedance supercapacitors at the output to enable efficient delivery of high power burst loads while a lithium-polymer battery provides back-up in the event of a failure of the ambient energy.
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