Abstract
This paper presents an SC voltage doubler-based voltage regulator for ultra-low power energy harvesting applications. It produces a stable 1.2-V power supply, using inputs from 0.63 to 1.8 V. External compensation and an on-chip output capacitor ensure good performance even with zero load current and any load capacitance. The regulator tolerates arbitrary input ramp-ups, and is immune to blackout and brownout. A stability analysis for the regulator control loop is presented. The regulator ASIC is implemented in a 180 nm CMOS process. The measured regulator peak power and current efficiency are 63 and 49 %, respectively. The performance has been characterized with load currents from zero to \(100\,\upmu\)A.
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This work received funding from the AUTOVOLT project granted by the Academy of Finland (Grant Number 140267) and the EffiNano project granted by Aalto University School of Electrical Engineering (Grant Number 10/2012), and Aalto ELEC Doctoral School.
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Salomaa, J., Pulkkinen, M. & Halonen, K. A microwatt switched-capacitor voltage doubler-based voltage regulator for ultra-low power energy harvesting systems. Analog Integr Circ Sig Process 88, 347–358 (2016). https://doi.org/10.1007/s10470-016-0708-2
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DOI: https://doi.org/10.1007/s10470-016-0708-2