Patent ID: 9495920
Filing Date: 2016-11-15
CPC Classification: G09G,G11C

Claim Text:
1. A shift register unit comprising a driving module, a first pull-down module, a second pull-down module, a third pull-down module and an output module; wherein the driving module is connected to the output module, and a connection point where the driving module is connected to the output module is a pull-up node; the driving module is configured to control a signal at the pull-up node to be at a first level when a forward selection signal is at the first level and a forward scan signal is at the first level; is configured to control the signal at the pull-up node to be at the first level when the forward selection signal is changed from the first level to a second level and the forward scan signal is at the first level; is configured to control the signal at the pull-up node to be at the second level when the forward scan signal is at the first level and a reverse selection signal is at a first level; is configured to control the signal at the pull-up node to be at the first level when the reverse selection signal is at the first level and the reverse scan signal is at the first level; is configured to control the signal at the pull-up node to be at the first level when the reverse selection signal is changed from the first level to the second level and the reverse scan signal is at the first level; and is configured to control the signal at the pull-up node to be at the second level when the reverse scan signal is at the first level and the forward selection signal is at the first level; the output module is configured to output a received clock signal from an output terminal of the shift register unit when the signal at the pull-up node is at the first level, and is configured to control the output terminal of the shift register unit to stop outputting the received clock signal when the signal at the pull-up node is at the second level; the first pull-down module is connected to the pull-up node, the output terminal of the shift register unit, and a second level signal input terminal respectively, the first pull-down module is configured to control both the pull-up node and the output terminal of the shift register unit to be connected to the second level signal input terminal when a received pull-down signal is at the first level and the signal at the pull-up node is at the second level; and is configured to control both the pull-up node and the output terminal of the shift register unit to be disconnected from the second level signal input terminal when the signal at the pull-up node is at the first level; wherein the pull-down signal is the signal among the forward scan signal and the reverse scan signal which is at the first level, or the pull-down signal is the clock signal, the second pull-down module is connected to the pull-up node and the second level signal input terminal respectively, and the second pull-down module is configured to control the pull-up node to be connected to the second level signal input terminal when the reverse scan signal is at the second level and a forward feedback signal is at the first level; and is configured to control the pull-up node to be disconnected from the second level signal input terminal when the reverse scan signal is at the first level or when the reverse scan signal is at the second level and the forward feedback signal is at the second level; wherein the forward feedback signal is a signal outputted from an output terminal of another shift register unit at a stage subsequent to that of the shift register unit; the third pull-down module is connected to the pull-up node and the second level signal input terminal respectively, and the third pull-down module is configured to control the pull-up node to be connected to the second level signal input terminal when the forward scan signal is at the second level and a reverse feedback signal is at the first level; and is configured to control the pull-up node to be disconnected from the second level signal input terminal when the forward scan signal is at the first level or when the forward scan signal is at the second level and the reverse feedback signal is at the second level; wherein, the reverse feedback signal is a signal outputted from an output terminal of another shift register unit at a stage previous to that of the shift register unit; wherein the forward selection signal is a signal output from the output terminal of another shift register unit at a stage previous to that of the shift register unit, and the reverse selection signal is a signal output from the output terminal of another shift register unit subsequent to that of the shift register unit.