Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Design of Pixel Circuit of Micro LED Display with Double Gate Thin Film Transistors

더블 게이트 박막 트랜지스터를 활용한 Micro LED 디스플레이 화소 회로 설계

  • Kim, Taesoo (School of Electronics and Information Engineering, Korea Aerospace University) ;
  • Jeon, Jaehong (School of Electronics and Information Engineering, Korea Aerospace University)
  • 김태수 (한국항공대학교 항공전자정보공학부) ;
  • 전재홍 (한국항공대학교 항공전자정보공학부)
  • Received : 2022.02.16
  • Accepted : 2022.03.25
  • Published : 2022.03.31
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Abstract

Due to the wavelength shift problem of micro LED caused by the change of current density, the active matrix driving pixel circuit that is used in OLED cannot be applied to micro LED displays. Therefore, we need a gray scale method based on modulation of duration time of light emission. In this study, we propose the PWM-controlled micro LED pixel circuit based on CMOS thin film transistors (TFTs). By adopting CMOS inverter structure, we can reduce the number of storage capacitors from the circuit and make the operating speed of the circuit faster. Most of all, our circuit is designed to make operating speed of PWM circuit faster by adopting feedback effect through double gate TFT structure. As a result, it takes about 4.7ns to turn on the LED and about 5.6ns to turn it off. This operating time is short enough to avoid the color distortion and help the precise control of the gray scale.

Keywords

Acknowledgement

본 연구는 경기도의 경기도 지역협력연구센터(GRRC) 사업의 일환으로 수행하였음. [GRRC-KAU-2021-B03, 극장용 영사기 및 스크린 대체를 위한 투음 디스플레이 개발]

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