Title :
A fully-integrated 0.18μm CMOS DC-DC step-down converter, using a bondwire spiral inductor
Author :
Wens, Mike ; Steyaert, Michiel
Author_Institution :
ESAT-MICAS, Katholieke Univ. Leuven, Leuven
Abstract :
A fully-integrated DC-DC step-down converter in a 0.18 mum 1.8 V CMOS technology is realized, with a bondwire spiral inductor and integrated MOS and MIM capacitors. The converter is designed to generate an output voltage of 1.8 V out of a 3.6 V power supply. No external components are required. The maximum power conversion efficiency is 65 %, for a voltage conversion ratio of 0.5. This is a 23 % improvement compared to a linear regulator. Higher values are likely to be reached using a converter with external components, which is not the case here. Stacked transistors are used to cope with the high voltage. A novel control system based on a constant on/off-time keeps the output voltage constant at load conditions from 0 mW to 300 mW. The converter operates in discontinuous, asynchronous switching mode. The switching frequency ranges from 20 Hz to 140 MHz.
Keywords :
CMOS integrated circuits; DC-DC power convertors; MIM devices; MOS capacitors; inductors; switching convertors; MIM capacitors; MOS capacitors; asynchronous switching mode; bondwire spiral inductor; discontinuous switching mode; frequency 20 Hz to 140 MHz; fully-integrated CMOS DC-DC step-down converter; linear regulators; maximum power conversion efficiency; power 0 mW to 300 mW; voltage 1.8 V; voltage 3.6 V; voltage conversion ratio; Bonding; CMOS technology; DC-DC power converters; Inductors; MIM capacitors; Power conversion; Power generation; Power supplies; Spirals; Voltage;
Conference_Titel :
Custom Integrated Circuits Conference, 2008. CICC 2008. IEEE
Conference_Location :
San Jose, CA
Print_ISBN :
978-1-4244-2018-6
Electronic_ISBN :
978-1-4244-2019-3
DOI :
10.1109/CICC.2008.4672009
