| 摘要 |
PURPOSE: To provide a drive circuit for a display which is composed of one- conductivity type TFTs to obtain a normal amplitude of output signal. CONSTITUTION: TFTs 101, 104 are turned on by an input pulse and goes into a floating state, when the potential on a node α reaches VDD-VthN. Accompanying turning on of TFT 105 is the potential on an output node is raised with a clock signal turned to Hi, while the potential on the gate electrode of the TFT 105 rises further to exceed VDD+VthN by the action of a capacitance 107 with the potential rise on the output node. Thus, the potential on the output node rises up to VDD according to the threshold of the TFT 105, without the occurrence of voltage drop. Then the next-stage output is inputted to TFTs 102, 103 to turn it on, causing the potential on the node α to lower to turn off the TFT 105, and to turn on a TFT 106 at the same time, and the output node potential goes to Lo. |
