Energy-Harvesting IC Plays Into Internet Of Things Ecosystem

When connected to either a solar cell or thermo-electric generator (TEG), STMicroelectronics’ new energy-harvesting IC integrates the functions needed to power electronic circuits from a few microwatts to several milliwatts, as well as recharge batteries. Harvesting ambient light or thermal energy to power small electronic devices not only reduces CO₂ emissions, but it eliminates batteries and power cabling, thus enabling the Internet of Things (IoT) ecosystem. The SPV1050 contains a buck-boost converter has a 180-mV to 8-V input-voltage range, which allows the device to connect to a TEG or indoor/outdoor solar-energy harvesting modules. Both 1.8- and 3.3-V regulators are available to directly power a companion MCU or wireless transmitter. Operating efficiency averages 90%, enabling fast battery charging even at low input-power levels. Maximum power-point tracking (MPPT) accuracy is 90% minimum, which augments energy extraction from solar or TEG sources. Battery-charging circuitry supports various battery types: lithium-ion, lithium-polymer, lithium thin-film solid-state, NiMH, and NiCd (and supercapacitors). An integrated battery-charging controller uses high-accuracy undervoltage and end-of-charge thresholds, while safe control logic prevents excessive discharging to extend battery life.

STMICROELECTRONICS