A Switched-Capacitor DC-DC Converter with Conversion Ratio Controller for Wide Output Power Range

Keywords: Energy Harvesting System (EHS), Inductor-based DC-DC Converter, Internet of Things (IoT), Switched-Capacitor (SC) DC-DC Converter

Abstract

The DC-DC converter is essential for all modern SoC (System on Chip) to provide proper supply voltage for each system block from the global supply voltage or the energy extracted by the energy harvesting system. Among them, especially IoT (Internet of Things) systems, which are increasing in demand, require DC-DC converters that occupy a small area and cover low-power area. However, the switched-capacitor DC-DC converter has a disadvantage of having a narrow output power range compared to inductor-based DC-DC converters. Therefore, the range of the output load current is limited, which may be a problem in some applications such as light sources driving DC-DC converter. In this paper, we focus on the technique of extending the output power range of the switched-capacitor DC-DC converter. The problems and limitations of the conventional structure were analyzed and based on this, an idea to expand the output power range of the switched-capacitor DC-DC converter was proposed. To prove the effectiveness of the proposed technique, a switched-capacitor DC-DC converter is designed and verified with 65nm CMOS process. Various simulations under different conditions were performed, and as a result, wide output load current range of 1 to 20 mA and good power conversion efficiency of up to 80.6% at 1mA output load current are achieved.

 

Author Biographies

Myeong Gyu Yang, Chung-Ang University

Myeong-Gyu Yang received the B.S. degrees at School of Electrical and Electronics Engineering from Chung-Ang University, Seoul, South Korea, in 2020, where he is currently working toward the M.S. degree in Electrical and Electronic Engineering. His current research interests include mixed-signal integrated circuit design, switched-capacitor dc-dc converter, energy harvesting systems

Kwang Hyun Baek, Chung-Ang University

Kwang-Hyun Baek received the B.S. and M.S. degrees from Korea University, Seoul, Korea, in 1990 and 1998, respectively. He received the Ph.D. degree in electrical engineering from the University of Illinois at Urbana-Champaign (UIUC), IL, USA, in 2002. From 2000 to 2006, he was with the Department of High-Speed Mixed-Signal ICs as a senior scientist at Rockwell Scientific Company, formerly Rockwell Science Center (RSC), Thousand Oaks, CA, USA. At RSC, he was involved in development of high-speed data converters (ADC/DAC) and direct digital frequency synthesizers (DDFS). He was also with Samsung Electronics from 1990 to 1996. Since 2006 he has been with the School of Electrical and Electronics Engineering, Chung-Ang University (CAU), Seoul, Korea, where he is a faculty member. His research interests include high-performance analog and digital circuits such as lowpower ADCs, high-speed DACs, hybrid frequency synthesizers (PLLs, DDFSs), high-speed interface circuits (CDRs, SerDes), PMIC, and near threshold-voltage (NTV) circuits.

Published
2022-06-30
How to Cite
Yang, M. G., Jang, C. H., & Baek, K. H. (2022). A Switched-Capacitor DC-DC Converter with Conversion Ratio Controller for Wide Output Power Range. Journal of Integrated Circuits and Systems, 8(3). Retrieved from http://jicas.idec.or.kr/index.php/JICAS/article/view/113
Section
Articles