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

摘要

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 VOUT1 and VOUT2. VOUT1 and VOUT2 are three and nine times higher than the harvester's output VIN, respectively. VOUT1 is used as a supply voltage for on-chip application circuits while VOUT2 is used as the charging voltage for a Li-ion secondary battery. The VBC achieves a high voltage conversion ratio (max. × 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 VOUT1 and VOUT2 were 396 and 0 μW, 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 μW, respectively.