EnOcean Inc.’s SMT100 tiny solar-powered wireless sensor module overcomes the challenges to efficient wireless sensing and power management. It also addresses creation, storage and management of power. Within its custom two-stage solar cell, one stage provides quick startup energy while the other charges an onboard energy reservoir. Designed to operate indoors, the device requires only 200 lux to generate energy (typical lighting values in a building range from 200 lux in hallways, 500 lux on desktops and up to 1200 lux in display cases).

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The unit comprises a) a solar cell energy source, b) an energy reservoir, c) analog and digital sensor connections, d) a microprocessor for sensor control, and e) a radio transmitter - all packed into a minuscule 0.8 inch x 1.6 inch x 0.4 inch footprint (2 cm x 4 cm x 1 cm). Despite its small size, STM100 stores sufficient energy to operate continuously for up to five days in complete darkness.

“EnOcean’s patented technology lets STM100 generate a surprisingly long-range radio signal with extremely minute amounts of harvested energy,” said Armin Anders, EnOcean’s vice president of Product Marketing. “With just 50 µWs, a standard EnOcean transmitter will comfortably send a signal 300 meters outdoors, 30 meters indoors through walls. The secret is in the signal duration; the entire process is initiated, undertaken and completed in approximately 1/1000 of a second.”

STM100’s platform supports a wide variety of sensors - temperature, gas, humidity, illumination, location, presence, etc. - to enable mobile, maintenance-free monitoring and control of buildings, factories, logistics and automobiles. The product is particularly helpful to sensor manufacturers of lighting, security and HVAC equipment. By offering three analog and four digital inputs and sophisticated measurement routines, it greatly simplifies sensor integration.

To simplify the OEMs' development of their wireless networks, EnOcean provides a family of receivers and transceiver/repeaters compatible with all of its switch and sensor modules. The proprietary radio technology is approved for use in Europe (ETSI), United States (FCC) and Canada (IC). SMT100s including solar cell, energy reservoir and radio are available in OEM quantities for less than $25.