A Level Shifter Using Aluminum-Doped Zinc Tin Oxide Thin Film Transistors with Negative Threshold Voltages

  • Hwang, Tong-Hun (Division of Electrical and Computer Engineering, Hanyang University) ;
  • Yang, Ik-Seok (Division of Electrical and Computer Engineering, Hanyang University) ;
  • Kim, Kang-Nam (Division of Electrical and Computer Engineering, Hanyang University) ;
  • Cho, Doo-Hee (Transparent Electronics Team, Electronics and Telecommunications Research Institute) ;
  • KoPark, Sang-Hee (Transparent Electronics Team, Electronics and Telecommunications Research Institute) ;
  • Hwang, Chi-Sun (Transparent Electronics Team, Electronics and Telecommunications Research Institute) ;
  • Byun, Chun-Won (Transparent Electronics Team, Electronics and Telecommunications Research Institute) ;
  • Kwon, Oh-Kyong (Division of Electrical and Computer Engineering, Hanyang University)
  • Published : 2009.10.12

Abstract

A new level shifter using n-channel aluminum-doped zinc tin oxide (AZTO) thin film transistors (TFTs) was proposed to integrate driving circuits on qVGA panels for mobile display applications. The circuit used positive feedback loop to overcome limitations of circuits designed with oxide TFTs which is depletion mode n-channel TFTs. The measured results shows that the proposed circuit shifts 10 V input voltage to 20 V output voltage and its power consumption is 0.46 mW when the supply voltage is 20 V and the operating frequency is 10 kHz.

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