US Patent 7068076 Semiconductor device and display device

A circuit capable of reducing a consumption current is provided for a digital display device composed of unipolar TFTs. There is provided a latch circuit for holding a digital video signal. According to the latch circuit, when the digital video signal is inputted to an input electrode of a TFT (101), a non-inverting output signal is outputted from an output electrode of the TFT (101) and an inverting output signal is outputted from output electrodes of TFTs (102 and 103). Two line outputs of non-inversion and inversion are obtained. Thus, when a buffer located in a subsequent stage is operated, a period for which a direct current path is produced between a high potential and a low potential of a power source can be shortened, thereby contributing to reduction in a consumption current.