A Thin Film Flexible Thermoelectric Generator with a Fully Electrical, Low Startup Voltage and High Ffficiency DC - DC Converter

In this paper, an energy harvesting system composed by a flexible thermoelectric generator (TEG) with a DC - DC converter is shown. The proposed generator has been produced by screen printing technology on 80 mu m thick common paper and thin Kapton foil and integrates about 280 thermocouples, for an output voltage of about 75mV with 5K of the thermal gradient, useful for wearable - oriented applications. To increase the voltage provided by TEG, a DC - DC converter is implemented in 65nm CMOS technology. It operates for an input voltage (V-IN) range from 80mV to 370mV. This converter achieves an automatic control based on pulse width modulation (PWM), that ensure IV output voltage (V-OUT), for the various input voltages. The peak efficiency is 73% at 370mV of input voltage.