3-D Microtransformers for DC-DC On-Chip Power Conversion

We address the miniaturization of power converters by introducing novel 3-D microtransformers with magnetic core for low-megahertz frequency applications. The core is fabricated by lamination and microstructuring of Metglas 2714A magnetic alloy. The solenoids of the microtransformers are wound aroun...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on power electronics 2015-09, Vol.30 (9), p.5088-5102
Main Authors: Moazenzadeh, Ali, Suarez Sandoval, Fralett, Spengler, Nils, Badilita, Vlad, Wallrabe, Ulrike
Format: Article
Language:English
Subjects:
3-D technology
Alloys
Amorphous magnetic materials
Controllers
DC-DC power conversion
Electric currents
Electromagnetics
Fabrication
Frequencies
Magnetic cores
Magnetic layered film
Metals
Micromachining
Microstructure
Saturation magnetization
Substrates
Transformer
Transformers
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We address the miniaturization of power converters by introducing novel 3-D microtransformers with magnetic core for low-megahertz frequency applications. The core is fabricated by lamination and microstructuring of Metglas 2714A magnetic alloy. The solenoids of the microtransformers are wound around the core using a ball-wedge wirebonder. The wirebonding process is fast, allowing the fabrication of solenoids with up to 40 turns in 10 s. The fabricated devices yield the high inductance per unit volume of 2.95 μH/mm 3 and energy per unit volume of 133 nJ/mm 3 at the frequency of 1 MHz. The power efficiency of 64-76% is measured for different turns ratio with coupling factors as high as 98%. To demonstrate the applicability of our passive components, two PWM controllers were selected to implement an isolated and a nonisolated switch-mode power supply. The isolated converter operates with overall efficiency of 55% and maximum output power of 136 mW; then, we experimentally demonstrate how we increased this efficiency to 71% and output power to 408 mW. The nonisolated converter can deliver an overall efficiency of 81% with a maximum output power of 515 mW. Finally, we benchmarked the results to underline the potential of the technology for power on-chip applications.
ISSN:0885-8993
1941-0107
DOI:10.1109/TPEL.2014.2368252