Harvesting push button powers electronics from your finger

Gemns G100 is the latest finger-powered energy harvester from WePower Technologies – in this case, a push-button with built-in wireless IoT sensor node.

Around 40mm in diameter and 70mm from end to end, it is designed to mount in a standard 22mm panel hole.

“G100 is an integrated, self-contained Bluetooth LE RF switch solution,” the company told Electronics Weekly. “Within the G100 enclosure is a WePower EHC100 charger board for energy extraction and a custom board containing the Bluetooth 5.0 module, FRAM and sensors. Each board is approximately 21mm x 26mm, with additional space available if required for other application considerations.”

The sensors include a three-axes accelerometer, temperature and barometric pressure.

WePower claims that the electricity generated is sufficient for other wireless formats including Zigbee Green Power, LoRa, Z-Wave and Thread, with up to 20dBm of output.

Load-dependent output curves

The generator uses both stationary and oscillating magnets toharvest kinetic energy through electromagnetic induction.

Across 5 to 50mA, 2.25mJ is available via the suggested 1.8V buck regulator (Renesas ISL9123), and 2.75mJ via the 3.3V buck-boost regulator (ISL9122).

A lifetime of one million cycles is expected, and operation is over -40 to +85°C.

A G100 energy harvesting push button data brief can be found here