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.