Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
권호 표지
DOI QR코드

DOI QR Code

Design of 2-Ch DC-DC Converter with Wide-Input Voltage Range of 2.9V~5.6 V for Wearable AMOLED Display

2.9V~5.6V의 넓은 입력 전압 범위를 가지는 웨어러블 AMOLED용 2-채널 DC-DC 변환기 설계

  • Lee, Hui-Jin (School of Electrical and Computer Engineering, Chungbuk National University) ;
  • Kim, Hak-Yun (Zinitix Co.) ;
  • Choi, Ho-Yong (School of Electrical and Computer Engineering, Chungbuk National University)
  • Received : 2020.08.31
  • Accepted : 2020.09.28
  • Published : 2020.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

This paper proposes a 2-ch DC-DC converter with a wide-input voltage range from 2.9V~5.6V for wearable AMOLED displays. For positive voltage VPOS, a boost converter is designed using an over-charged voltage permissible circuit (OPC) which generates a normal output voltage even if over-input voltage is applied, and a SPWM-PWM dual mode with 3-segmented power transistors to improve efficiency at light load. For negative voltage VNEG, a 0.5x regulated inverting charge pump is designed to increase power efficiency. The proposed DC-DC converter was designed using a 0.18-㎛ BCDMOS process. Simulation results show that the proposed DC-DC converter generates VPOS voltages of 4.6 V and VNEG voltage of -0.6V~-2.3V for input voltage of 2.9V to 5.6V. In addition, it has power efficiency of 49%~92%, output ripple voltage has less than 20 mV for load current range of 1 mA~70 mA.

본 논문에서는 2.9 V ~ 5.6V의 넓은 입력 전압 범위를 가지는 웨어러블 AMOLED용 2-채널 DC-DC 변환기를 설계한다. 양전압 VPOS는 과도한 입력전압이 인가된다 하더라도 정상 출력 전압을 생성되는 OPC를 내장하고, 경부하 효율을 제고하기 위한 SPWM-PWM 듀얼모드 및 파워 트랜지스터 3-분할을 적용한 부스트 변환기로 설계한다. 음전압 VNEG는 전력 효율을 높이기 위해 0.5x 인버팅 차지펌프를 이용해 설계한다. 제안된 DC-DC 변환기는 0.18-㎛ BCDMOS 공정으로 설계하였다. DC-DC 변환기는 2.9V~5.6V의 입력 전압에 대해 4.6V의VPOS와 -0.6V~-2.3V의 VNEG 전압을 생성한다. 또한 1mA~70mA 부하전류에서 49%~92%의 전력효율과 최대 20mV의 출력 리플을 가졌다.

Keywords

References

  1. S. Forrest, P. Burrows, and M. Thompson, "The Dawn of Organic Electronics," IEEE Spectrum, vol.37, no.8, pp.29-34, 2000. https://doi.org/10.1109/6.861775
  2. Ying Wang, "Design for OLED microdisplay," Proc. of 2010 Asia Pacific Conf. in Microelectronics and Electronics, pp.206-209, 2010. DOI: 10.1109/PRIMEASIA.2010.5604924
  3. S.-W. Hong, S.-H. Park, T.-H. Kong, and G.-H.Cho, "Inverting buck-boost DC-DC converter for mobile AMOLED display using real-time selftuned minimum power-loss tracking (MPLT) scheme with lossless soft-switching for discontinuous conduction mode," IEEE J. Solid-State Circuits, vol.50, no.10, pp.2380-2393, 2015. DOI: 10.1109/JSSC.2015.2450713
  4. C.-S. Chae, H.-P Le, K.-C Lee, G.-H Cho and G.-H Cho, "A Single-Inductor Step-Up DC-DC Switching Converter with Bipolar Outputs for Active Matrix OLED Mobile Display Panels," IEEE J. Solid-State Circuits, vol.44, no.2, pp.509-524, 2009. DOI: 10.1109/ISSCC.2007.373625
  5. B.-C. Kwak, S.-K Hong and O.-K Kwon, "A Highly Power-Efficient Single-Inductor Bipolar-Output DC-DC Converter Using Hysteretic Skipping Control for OLEDon-Silicon Microdisplay," IEEE T. Circuits and Systems II, vol.65, no.12, pp.2017-2021, 2018. DOI: 10.1109/TCSII.2018.2815994
  6. F. Mao, Y. Lu, E. Bonizzoni, F. Boera, M. Huang, F. Maloberti and R.P Martins, "A Power- Efficient Hybrid Single-Inductor Bipolar-Output DC-DC Converter with Floating Negative Output for AMOLED Displays," in Proc. IEEE Custom Integr. Circuits Conf. (CICC), pp.1-4, 2020. DOI: 10.1109/CICC48029.2020.9075940
  7. D. Salerno and R. Korsunsky, "Practical considerations in the design of lithium-ion battery protection systems," in Proc. 13th IEEE Appl. Power Electron. Conf. Expo., vol.2, pp.700-707, 1998. DOI: 10.1109/APEC.1998.653975
  8. Hak-Yun Kim, Myeong-Hak Lee, Young-Ho Shin, Jin-Won Kim, Nam-Soo Kim, and Ho-Yong Choi, "Dual-mode Inverting Buck-boost Converter using Set-time Variable PWM Method," Journal of Semiconductor Technology and Science. vol.18, no.4, 2018. DOI: 10.5573/JSTS.2018.18.4.423
  9. Seung-Ki Jeon, Hui-Jin Lee, Ho-Yong Choi, "Design of Highly Integrated 3-Channel DC-DC Converter Using PTWS for Wearable AMOLED," Institute of Korean Electrical and Electronics Engineers, Vol.23, No.4, pp.1061-1067, 2019. DOI: 10.7471/ikeee.2019.23.3.1061