Patent ID: 6788757
Filing Date: 2004-09-07
Classification: G11C

Abstract:
A bi-directional shift-register circuit comprising thin film transistors for outputting data in different sequence according to a forward-scan control signal and a backward-scan control signal output by a scanning-sequence control circuit, comprising:a first shift-register unit with a first-stage input terminal, a first-stage control terminal, and a first-stage output terminal for outputting a first output signal; a second shift-register unit with a second-stage input terminal coupled to the first-stage output terminal and a third-stage output terminal, a second-stage control terminal and a second-stage output terminal for outputting a second output signal, wherein the second-stage control terminal is selectively coupled to a first-stage output terminal or the third-stage output terminal and disables the second shift-register unit according to a first output signal or a third output signal; a third shift-register unit with a third-stage input terminal, a third-stage control terminal and the third-stage output terminal for outputting the third output signal; and a switching circuit for electrically connecting the third-stage output terminal with the second-stage control terminal when receiving the forward-scan control signal, and electrically connecting the first-stage output terminal with the second-stage control terminal when receiving the backward-scan control signal.