1. A Gain/Efficiency-Improved Serial- Parallel Switched-Capacitor Step-Up DC– DC Converter IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS—I: REGULAR PAPERS, VOL. 60, NO. 10, OCTOBER 2013 Yuen-Haw Chang and Song-Ying Kuo Date:2014/02/25 Reporter:Chen-Han Tsai 1

2. Outline INTRODUCTION CONFIGURATION OF SPSCC FORMULATION OF SPSCC ANALYSIS AND DESIGN OF SPSCC EXAMPLE OF SPSCC CONCLUSION PERSONAL REMARK 2

3. INTRODUCTION(1/2) The switched-capacitor converter (SCC), possessed of the charge pump structure, is one of solutions to DC-DC power conversion because it has only semiconductor switches and capacitors. Unlike traditional converters, the inductor-less SCC has light weight and small volume. 3

4. INTRODUCTION(2/2) A new SPSCC is proposed for reaching the goals of higher voltage gain, fewer capacitor count, and simple control circuit. Anaptive-conversion-ratio(ACR) control is suggested to change stage number for a proper gain to improve efficiency. 4

5. CONFIGURATION OF SPSCC(1/3) 5

6. CONFIGURATION OF SPSCC(2/3) Phase I III Phase II Phase IV 6

7. CONFIGURATION OF SPSCC(3/3) 7

8. FORMULATION OF SPSCC(1/4) Phase I III 8

9. FORMULATION OF SPSCC(2/4) Phase II 9

10. FORMULATION OF SPSCC(3/4) Phase IV 10

11. FORMULATION OF SPSCC(4/4) 11

12. ANALYSIS AND DESIGN OF SPSCC(1/3) Steady-State Analysis and Conversion Ratio 12

13. ANALYSIS AND DESIGN OF SPSCC(2/3) ACR-Based Power Efficiency 13

14. ANALYSIS AND DESIGN OF SPSCC(3/3) 14

15. EXAMPLE OF SPSCC 15 m=3 n=3 Vref=47.2v rp=0.033% η = 98.1%

16. EXAMPLE OF SPSCC(1/4) 16 m=3 n=2 Vref=35.6v rp=0.034% η = 98.5%

17. EXAMPLE OF SPSCC(2/4) 17 m=3 n=1 Vref=26.8v rp=0.036% η = 98.7%

18. EXAMPLE OF SPSCC(3/4) 18

19. EXAMPLE OF SPSCC(4/4) 19 m=4 n =4m=4 n=3 m=3 n=3

20. CONCLUSION(1/2) The SPSCC needs no magnetic element, so I.C. fabrication will be promising. With bidirectional switches, it is helpful to integrate various topologies into one structure. 20

21. CONCLUSION(2/2) By using ACR, the efficiency is improved much better than that just by the fixed stage number,especially for the lower output. By using PWM, the output regulation is enhanced as well as robustness to source/loading variation. 21

22. PERSONAL REMARK Switches used too, the cost increases. Pressure power is too small, practical application would be more difficult. 22

23. Q&A Thank for your attention 23