Pixel circuit and display device including same
A pixel circuit of a display device presented herein includes a driving element including a first electrode connected to a first node, a gate electrode connected to a second node, and a second electrode connected to a third node; a first switch element connecting the second node to the third node; a second switch element applying a data voltage to the first node; a third switch element connecting a pixel driving voltage line to the first node; a fourth switch element connecting the third node to a fourth node; a fifth switch element applying a first initialization voltage to the second node; a sixth switch element applying a second initialization voltage to the fourth node; a capacitor connected to the pixel driving voltage line and the second node; and a light-emitting element connected to the fourth node and a low potential power voltage line.
1 . A pixel circuit, comprising:
a driving element including a first electrode connected to a first node of the pixel circuit, a gate electrode connected to a second node of the pixel circuit, and a second electrode connected to a third node of the pixel circuit;
a first switch element connecting the second node to the third node in response to a first gate signal;
a second switch element applying a data voltage to the first node in response to a second gate signal;
a third switch element connecting a pixel driving voltage line of the pixel circuit to the first node in response to a third gate signal;
a fourth switch element connecting the third node to a fourth node of the pixel circuit in response to the third gate signal;
a fifth switch element applying a first initialization voltage to the second node in response to a fourth gate signal;
a sixth switch element applying a second initialization voltage to the fourth node in response to the second gate signal;
a capacitor connected to the pixel driving voltage line and the second node; and
a light-emitting element connected to the fourth node and a low potential power voltage line of the pixel circuit.
2 . The pixel circuit of claim 1 , wherein:
the pixel circuit is driven in an order of an initialization step, an on-bias stress (OBS) step, a sampling step, and a light emission step,
in the initialization step, the fifth switch element is turned and a voltage of the second node is discharged to the first initialization voltage, and the sixth switch element is turned on and a voltage of the fourth node is discharged to the second initialization voltage, and
in the OBS step, the second switch element is turned on and the data voltage of a previous frame is applied to the first node.
3 . The pixel circuit of claim 2 , wherein, in the sampling step, both the first switch element and the second switch element are turned on and the data voltage of a current frame is applied to the first node.
4 . A display device, comprising:
a pixel array with a plurality of data lines, a plurality of gate lines, and a plurality of pixel circuits;
a data driver outputting a data voltage to the plurality of data lines; and
a gate driver outputting gate signals to the plurality of gate lines,
wherein each of the plurality of pixel circuits comprises:
a driving element including a first electrode connected to a first node of the pixel circuit, a gate electrode connected to a second node of the pixel circuit, and a second electrode connected to a third node of the pixel circuit;
a first switch element connecting the second node to the third node in response to a first gate signal;
a second switch element applying the data voltage to the first node in response to a second gate signal;
a third switch element connecting a pixel driving voltage line to the first node in response to a third gate signal;
a fourth switch element connecting the third node to a fourth node in response to the third gate signal;
a fifth switch element applying a first initialization voltage to the second node in response to a fourth gate signal;
a sixth switch element applying a second initialization voltage to the fourth node in response to the second gate signal;
a capacitor connected to the pixel driving voltage line and the second node; and
a light-emitting element connected to the fourth node and a low potential power voltage line.
5 . The display device of claim 4 , wherein:
each of the plurality of pixel circuits is driven in an order of an initialization step, an on-bias stress (OBS) step, a sampling step, and a light emission step,
in the initialization step, the fifth switch element is turned on and a voltage of the second node is discharged to the first initialization voltage, and the sixth switch element is turned on and a voltage of the fourth node is discharged to the second initialization voltage, and
in the OBS step, the second switch element is turned on and the data voltage of a previous frame is applied to the first node.
6 . The display device of claim 5 , wherein, in the sampling step, both the first switch element and the second switch element are turned on and the data voltage of a current frame is applied to the first node.