A 10 mW-output power range and 88.1% efficiency reconfigurable DC-DC converter with clockless-sampling and pile-up technique for dual-source energy harvesting

Abstract

This paper presents a single-inductor triple-input dual-output buck–boost converter for the dual-source energy harvesting application. The converter employs the proposed series pile-up synchronized harvesting technique to improve the conversion efficiency at low input voltage and the system’s output power range. In parallel, to improve the tracking accuracy, a maximum power point tracking (MPPT) technique with coarse and fine tuning is incorporated into the harvester. In addition, to enable continuous energy extraction from transducers, a clockless-sampling technique is proposed. Implemented in the TSMC 0.18-$\mu$m standard CMOS process, the converter achieves a peak conversion efficiency of 88.1% and a maximum output power of 10 mW at $V_{\text{OUT}}=1.2V$.