Some analog building blocks for TFT circuits

摘要

The analog circuits fabricated by the amorphous and/or polycrystalline silicon TFT suffer from very wide deviation effects of the threshold voltage Vth and the current gain β. This paper proposes some analog building blocks for TFT circuits, in which the techniques to reduce the effects caused by the threshold voltage and the current gain β mismatch of the transistors are used. First, Vth and β deviation-free differential amplifier is discussed. Second, Vth deviation-free current source is proposed. Finally, Vth and β deviation-free class A amplifier is presented. The test chip to verify the proposed idea has been simulated and designed using VDEC design environment.