Scan driver and display device including the same and an electronic device
A scan driver includes a first scan driving circuit sequentially outputting gate scan signals to scan signal lines during an active period, wherein the first scan driving circuit includes: an n-th stage supplying a gate-on voltage to a pull-up node in response to a first gate control signal of a display driver circuit; output control parts sharing a pull-up node of the n-th stage and sequentially outputting the gate scan signals during an enable period in which the gate-on voltage is supplied to the pull-up node; at least one carry output part sharing the pull-up node of the n-th stage and outputting at least one carry signal during the enable period; and at least one node voltage control part controlling a voltage magnitude of the gate-on voltage charged to the pull-up node during the enable period in response to a pull-up control signal of the display driving circuit.
1 . A scan driver comprising: a first scan driving circuit that sequentially outputs gate scan signals to scan signal lines during an active period for a frame, wherein the first scan driving circuit includes: an n-th stage that supplies a gate-on voltage to a pull-up node in response to a first gate control signal of a display driver circuit, where n is a positive integer; a plurality of output control parts that shares a pull-up node of the n-th stage and that sequentially outputs the gate scan signals during an enable period in which the gate-on voltage is supplied to the pull-up node; at least one carry output part that shares the pull-up node of the n-th stage and outputs at least one carry signal during the enable period; and at least one node voltage control part that controls a voltage magnitude of the gate-on voltage charged to the pull-up node during the enable period in response to a pull-up control signal of the display driving circuit, wherein the at least one node voltage control part is electrically connected to the pull-up node of the n-th stage and electrically shares the pull-up node, and adjusts the voltage magnitude of the pull-up node according to a change in voltage magnitude of the pull-up control signal input from the display driving circuit during the enable period of the pull-up node, and the display driving circuit varies the pull-up control signal to a first voltage magnitude greater than a selected magnitude of the gate-on voltage during an initial portion and a final portion of the enable period, and a second voltage magnitude substantially equal to the selected magnitude of the gate-on voltage during a middle portion of the enable period, and supplies the varied pull-up control signal to a pull-up control transistor during the enable period of the pull-up node.
2 . The scan driver of claim 1 , further comprising:
a second scan driving circuit that sequentially supplies sensing control signals to the sensing control lines during the active period for the frame based on a second gate control signal from the display driving circuit,
wherein the second scan driving circuit sequentially supplies the sensing control signals to the sensing control lines arranged for each horizontal line to control a pixel driving voltage of each pixel for each horizontal line to be output to a data driving circuit.
3 . The scan driver of claim 1 , wherein
a plurality of n-th stages are cascadedly connected to each other, and
the plurality of output control parts are electrically connected to the pull-up node of the n-th stage to electrically share the pull-up node, and are connected in a series or parallel structure to the pull-up node of the n-th stage.
4 . The scan driver of claim 3 , wherein first to fourth output control parts of the plurality of output control parts sequentially output n-th to n+3-th gate scan signals to n-th to n+3-th gate lines, in response to first to fourth line select signals sequentially input in parts of at least one horizontal period during the enable period of the pull-up node.
5 . The scan driver of claim 4 , wherein
each of the first to fourth output control parts includes a pull-up transistor and a pull-down transistor, and
the pull-up transistor is turned on by the gate-on voltage of the pull-up node and outputs at least one line select signal input to a line select signal input terminal to each scan signal line.
6 . The scan driver of claim 3 , wherein the at least one carry output part is electrically connected to the pull-up node of the n-th stage and electrically shares the pull-up node, and outputs the at least one carry signal to stages disposed at a front end and a rear end in response to a carry select signal selectively input from the display driving circuit during the enable period of the pull-up node.
7 . The scan driver of claim 6 , wherein
the at least one carry output part includes a pull-up transistor and a pull-down transistor, and
the pull-up transistor is turned on by the gate-on voltage of the pull-up node and outputs the carry select signal input to the carry select signal input terminal to front-end and rear-end stages of a previous stage and a next stage.
8 . The scan driver of claim 1 , wherein the at least one node voltage control part includes:
a pull-up control transistor that is turned on by the gate-on voltage of the pull-up node and outputs the pull-up control signal input to a first electrode to a second electrode; and
a pull-up capacitor having a first side electrode connected to the pull-up node and a second side electrode connected to the second electrode of the pull-up control transistor in a parallel structure with the pull-up control transistor.
9 . The scan driver of claim 8 , wherein
the pull-up control transistor supplies the pull-up control signal from the display driving circuit to the second electrode of the pull-up capacitor, in case that the pull-up control transistor is turned on by the gate-on voltage of the pull-up node, and
the pull-up capacitor maintains the voltage magnitude of the pull-up node connected to the first side electrode according to the voltage magnitude of the pull-up control signal input to the second side electrode.
10 . The scan driver of claim 9 , wherein
the pull-up capacitor controls the voltage magnitude of the pull-up node according to the first voltage magnitude and the second voltage magnitude of the pull-up control signal input to the second side electrode.
11 . A display device comprising: a plurality of pixels arranged in a display area of a display panel; a display driving circuit that controls data voltages supplied to the plurality of pixels and image display timing of the pixels; and a scan driver that drives scan signal lines and sensing control lines of the display panel during an active period for a frame, wherein the scan driver includes a first scan driving circuit that sequentially outputs gate scan signals to scan signal lines during an active period for the frame, and the first scan driving circuit includes: an n-th stage that supplies a gate-on voltage to a pull-up node in response to a first gate control signal of a display driver circuit; a plurality of output control parts that share a pull-up node of the n-th stage and sequentially output the gate scan signals during an enable period in which the gate-on voltage is supplied to the pull-up node; at least one carry output part that shares the pull-up node of the n-th stage and outputs at least one carry signal during the enable period; and at least one node voltage control part that controls a voltage magnitude of the gate-on voltage charged to the pull-up node during the enable period in response to a pull-up control signal of the display driving circuit, wherein the at least one node voltage control part is electrically connected to the pull-up node of the n-th stage and electrically shares the pull-up node, and adjusts the voltage magnitude of the pull-up node according to a change in voltage magnitude of the pull-up control signal input from the display driving circuit during the enable period of the pull-up node, and the display driving circuit varies the pull-up control signal to a first voltage magnitude greater than a selected magnitude of the gate-on voltage during an initial portion and a final portion of the enable period, and a second voltage magnitude substantially equal to the selected magnitude of the gate-on voltage during a middle portion of the enable period, and supplies the varied pull-up control signal to a pull-up control transistor during the enable period of the pull-up node.
12 . The display device of claim 11 , wherein
a plurality of n-th stages are cascadedly connected to each other, and
the plurality of output control parts are electrically connected to the pull-up node of the n-th stage to electrically share the pull-up node, and are connected in a series or parallel structure to the pull-up node of the n-th stage.
13 . The display device of claim 12 , wherein first to fourth output control parts of the plurality of output control parts sequentially output n-th to n+3-th gate scan signals to n-th to n+3-th gate lines, in response to first to fourth line select signals sequentially input in parts of at least one horizontal period during the enable period of the pull-up node.
14 . The display device of claim 11 , wherein the at least one node voltage control part includes:
a pull-up control transistor that is turned on by the gate-on voltage of the pull-up node and outputs a pull-up control signal input to a first electrode to a second electrode; and
a pull-up capacitor having a first side electrode connected to the pull-up node and a second side electrode connected to the second electrode of the pull-up control transistor in a parallel structure with the pull-up control transistor.
15 . The display device of claim 14 , wherein
the pull-up control transistor supplies the pull-up control signal from the display driving circuit to the second electrode of the pull-up capacitor, in case that turned on by the gate-on voltage of the pull-up node, and
the pull-up capacitor maintains the voltage magnitude of the pull-up node connected to the first side electrode according to the voltage magnitude of the pull-up control signal input to the second side electrode.
16 . An electronic device comprising: a display device comprising: a plurality of pixels arranged in a display area of a display panel; a display driving circuit that controls data voltages supplied to the plurality of pixels and image display timing of the pixels; and a scan driver that drives scan signal lines and sensing control lines of the display panel during an active period for a frame, wherein the scan driver includes a first scan driving circuit sequentially outputting gate scan signals to scan signal lines during an active period for the frame, and the first scan driving circuit includes: an n-th stage that supplies a gate-on voltage to a pull-up node in response to a first gate control signal of a display driver circuit; a plurality of output control parts that share a pull-up node of the n-th stage and sequentially output the gate scan signals during an enable period in which the gate-on voltage is supplied to the pull-up node; at least one carry output part that shares the pull-up node of the n-th stage and outputs at least one carry signal during the enable period; and at least one node voltage control part that controls a voltage magnitude of the gate-on voltage charged to the pull-up node during the enable period in response to a pull-up control signal of the display driving circuit, wherein the at least one node voltage control part is electrically connected to the pull-up node of the n-th stage and electrically shares the pull-up node, and adjusts the voltage magnitude of the pull-up node according to a change in voltage magnitude of the pull-up control signal input from the display driving circuit during the enable period of the pull-up node, and the display driving circuit varies the pull-up control signal to a first voltage magnitude greater than a selected magnitude of the gate-on voltage during an initial portion and a final portion of the enable period, and a second voltage magnitude substantially equal to the selected magnitude of the gate-on voltage during a middle portion of the enable period, and supplies the varied pull-up control signal to a pull-up control transistor during the enable period of the pull-up node.