A Regulated Charge Pump With a Low-Power Integrated Optimum Power Point Tracking Algorithm for Indoor Solar Energy Harvesting

• Published in: IEEE transactions on circuits and systems. II, Express briefs Vol. 58; no. 12; pp. 802 - 806
• Main Authors: Kim, Jungmoon, Kim, Jihwan, Kim, Chulwoo
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2011; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Batteries; Battery charger; Capacitors; charge pump (CP); Circuits; Electric potential; Energy harvesting; Harvesting; Indoor; maximum power point tracking (MPPT); Optimization; optimum power point tracking (OPPT); photovoltaic (PV) systems; Photovoltaic cells; Power generation; Solar energy; solar energy harvesting; Solar power generation; Solid state circuits; Voltage control; Wireless sensor networks; wireless sensor networks (WSNs)
• ISSN: 1549-7747; 1558-3791
• DOI: 10.1109/TCSII.2011.2173971

This brief presents a regulated charge pump (CP) with an integrated optimum power point tracking (OPPT) algorithm designed for indoor solar energy harvesting. The proposed OPPT circuit does not require a current sensor that consumes power proportionally to the load. The solar cell voltage is regulated at the optimum power point; the CP output is regulated according to the target voltage. The controller of the OPPT circuit and CP dissipates only 450 nW; thus, the proposed technique is appropriate for indoor solar energy harvesting applications under dim lighting conditions.