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

다국어 초록 (Multilingual 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 with 65nm CMOS process, and this paper is based on simulations. 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.

참고문헌 (Reference)

1 M. Manninger, "Power management for portable devices" 2007

2 Hanh-Phuc Le, "Design Techniques for Fully Integrated Switched-Capacitor Voltage Regulators" 2015

3 H. Le, "Design Techniques for Fully Integrated Switched-Capacitor DC-DC Converters" 46 (46): 2120-2131, 2011

4 Michael Dougles Seeman, "Analytical and Practical Analysis of Switched-Capacitor DC-DC Converters" 2006

5 Y. Jiang, "Algebraic Series-Parallel-Based Switched-Capacitor DC–DC Boost Converter with Wide Input Voltage Range and Enhanced Power Density" 54 (54): 3118-3134, 2019

6 Z. Hua, "A Reconfigurable Dual-Output Switched-Capacitor DC-DC Regulator with SubHarmonic Adaptive-On-Time Control for Low-Power Applications" 50 (50): 724-736, 2015

7 X. Liu, "A Highly Efficient Reconfigurable Charge Pump Energy Harvester with Wide Harvesting Range and Two-Dimensional MPPT for Internet of Things" 51 (51): 1302-1312, 2016

8 H. Kim, "A Dual-Mode Continuously Scalable-ConversionRatio SC Energy Harvesting Interface With SC-Based PFM MPPT and Flying Capacitor Sharing Scheme" 56 (56): 2724-2735, 2021

9 Michael Dougles Seeman, "A Design Methodology for Switched-Capacitor DC-DC Converters" 2009

10 D. El-Damak, "A 93% efficiency reconfigurable switched-capacitor DC-DC converter using on-chip ferroelectric capacitors" 374-375, 2013

11 Z. Hua, "A 1.2-A DualOutput SC DC–DC Regulator with Continuous GateDrive Modulation Achieving ≤0.01-mV/mA Cross Regulation" 56 (56): 1576-1587, 2021

12 J. -H. Tsai, "A 1 V Input, 3 V-to-6 V Output, 58%-Efficient Integrated Charge Pump with a Hybrid Topology for Area Reduction and an ImprovedEfficiency by Using Parasitics" 50 (50): 2533-2548, 2015

13 D. Lutz, "12.4 A 10mW fully integrated 2-to-13V-input buck-boost SC converter with 81.5% peak efficiency" 224-225, 2016

14 Z. Hua, ""A cross-regulation-free triple-output switched-capacitor DC-DC regulator for energyharvesting applications" 352-355, 2013