An Autonomous Piezoelectric Energy Harvesting IC Based on a Synchronous Multi-Shot Technique Pierre Gasnier, Jérôme Willemin, Sebastien Boi sseau, Ghislain Despess e, Cyril Condemine, Guillaume Gouvernet, and Jean-Jacques Chaillout

Abstract

This paper presents a fully autonomous integrated circuit (IC) dedicated to piezoelectric harvesters. The novel Multi-Shot Synchronous Electri c Charge Extraction (MS-SECE) performed by the IC optimizes the energy transfer from a highly charged piezoelectric harvester to a low volt age storage element. The system deals with piezoelectric powers in the 10 µW to 1 mW range and handles very high piezoelectric voltage values ( 100 V) thanks to the off-chip components around th eI C .T h eI Ch a s been fabricated in AMS 0.35 µm 3.3 V technology and its low power consumption (1 µW @ 5 Hz) is particularly suitable for low frequency harvesters. MS-SECE increas es the extracted power compared to the Maximum Power Point Tracking (MPPT) tech- nique but it also improves the ef ficiency by up to 25% compared to standard SECE. Furthermore, MS -SECE allows the use of small off-chip components: an ef ficiency of 61% has been reached with a 125 mm 3 coupled-inductor. Finally, the proposed power management circuit self-start s, works without any battery and its overall volume is expected to be less than 1 cm 3.