Title
Design of Low-Voltage Integrated Step-up Oscillators with Microtransformers for Energy Harvesting Applications
Abstract
This paper describes the modeling of startup circuits in battery-less micropower energy harvesting systems and investigates the use of bond wire micromagnetics. The analysis focuses on step-up Meissner oscillators based on magnetic core transformers operating with input voltages down to $approx$100 mV, e.g., from thermoelectric generators. As a key point, this paper examines the effect of core losses and leakage inductances on the startup requirements obtained with the classical Barkhausen criterion, and demonstrates the minimum transconductance for oscillations to occur. For validation purposes, a step-up oscillator IC is fabricated in a STMicroelectronics 0.32 $mu{rm m}$ technology, and connected to two bond wire microtransformers, respectively, with a 1:38 MnZn ferrite core and with a 1:52 ferromagnetic low-temperature co-fired ceramic (LTCC) core. Coherently with the proposed model, experimental measurements show a minimum startup voltage of 228 mV for the MnZn ferrite core and of 104 mV for the LTCC core.
Year
DOI
Venue
2015
10.1109/TCSI.2015.2423796
IEEE Transactions on Circuits and Systems
Keywords
Field
DocType
Bond wire magnetics, energy harvesting, integrated circuits, leakage inductances, magnetic losses, magnetic materials, step-up oscillators, transformers
Micropower,Barkhausen stability criterion,Voltage,Ferrite core,Electronic engineering,Magnetic core,Low voltage,Transconductance,MOSFET,Electrical engineering,Mathematics
Journal
Volume
Issue
ISSN
62
7
1549-8328
Citations 
PageRank 
References 
3
0.47
0
Authors
5
Name
Order
Citations
PageRank
Enrico Macrelli130.47
Aldo Romani261.22
Rudi Paolo Paganelli330.81
Antonio Camarda451.21
Marco Tartagni550.85