Pixel Circuit and Display Device Including the Same

A pixel circuit comprising:

• a first voltage node to which a pixel driving voltage is applied;
• a second voltage node to which a cathode voltage that is less than the pixel driving voltage is applied;
• a driving element including a first electrode to which the pixel driving voltage is applied, a gate electrode connected to a first node, and a second electrode connected to a second node;
• a light emitting element including an anode electrode and a cathode electrode, the light emitting element configured to be driven by a current from the driving element;
• a capacitor connected between the first node and the second node;
• a first switch element connected between a data line to which a data voltage is applied and the first node, the first switch element configured to be turned on in response to a first gate signal;
• a second switch element connected between the second node and the second voltage node, the second switch element configured to be turned on in response to a second gate signal;
• a third switch element connected between a third voltage node to which an initialization voltage is applied and the first node, the third switch element configured to be turned on in response to a third gate signal;
• and
• a fourth switch element connected between the first voltage node and the first electrode of the driving element, the fourth switch element configured to be turned on in response to a fourth gate signal,
• wherein the cathode electrode of the light emitting element is connected to the second voltage node.

A display device comprising:

• a display panel comprising a plurality of data lines, a plurality of gate lines, a plurality of power lines, and a plurality of pixel circuits;
• a data driver configured to output data voltages of pixel data to the plurality of data lines;
• and
• a gate driver configured to sequentially supply gate signals to plurality of gate lines,
• wherein each of the plurality of pixel circuits includes:
• a first voltage node to which a pixel driving voltage is applied;
• a second voltage node to which a cathode voltage that is less than the pixel driving voltage is applied;
• a driving element including a first electrode to which the pixel driving voltage is applied, a gate electrode connected to a first node, and a second electrode connected to a second node;
• a light emitting element including an anode electrode and a cathode electrode, the light emitting element configured to be driven by a current from the driving element;
• a capacitor connected between the first node and the second node;
• a first switch element connected between a data line from the plurality of data lines to which a data voltage from the data voltages is applied and the first node, the first switch element configured to be turned on in response to a first gate signal;
• and
• a second switch element connected between the second node and the second voltage node, the second switch element configured to be turned on in response to a second gate signal,
• wherein the cathode electrode of the light emitting element is connected to the second voltage node.