Fully-Integrated High-Conversion-Ratio Dual-Output Voltage Boost Converter With MPPT for Low-Voltage Energy Harvesting.

This paper proposes a fully-integrated high-conversion-ratio dual-output voltage boost converter (VBC) with maximum power point tracking (MPPT) circuits for low-voltage energy harvesting. The VBC consists of two voltage generators that generate V\mathrm { OUT1} and V\mathrm { OUT2} . V\mathrm { OUT1} and V\mathrm { OUT2} are three and nine times higher than the harvester’s output V\mathrm { IN} , respectively. V\mathrm { OUT1} is used as a supply voltage for on-chip application circuits while V\mathrm { OUT2} is used as the charging voltage for a Li-ion secondary battery. The VBC achieves a high voltage conversion ratio (max. \times \,\,9 ) and a high power conversion efficiency. The MPPT circuits control the operating frequencies of the CPs to extract maximum power at each output. The measurement results demonstrated that the circuit converted a 0.59 V input to a 1.41 V output with 75.8% efficiency when the output powers of V\mathrm { OUT1} and V\mathrm { OUT2} were 396 and 0~\mu \text {W}$ , respectively, and a 0.62 V input to a 4.54 V output with 49.1% efficiency when the output powers were 0 and 114~\mu \text {W} , respectively. [ABSTRACT FROM PUBLISHER]