Pixel, organic light emitting display device using the same, and method of driving the organic light emitting display device
A pixel includes an organic light emitting diode (OLED), a pixel circuit, and first and second transistors. The OLD includes a cathode electrode connected to a second power source. The pixel circuit includes a driving transistor having a gate electrode initialized by a third power source. The driving transistor controls the amount of current flowing from a first power source to the second power source via the OLED. The first transistor is connected between a fourth power source and the second power source and an anode electrode of the OLED. The first transistor is turned on based on a scan signal is supplied to a scan line. The second transistor is connected between a data line and the pixel circuit. The second transistor is turned on when the scan signal is supplied to the ith scan line.
1. A pixel comprising:
a driving transistor connected to a first node and having a gate electrode connected to a second node, the first node connected to a first power source;
a light emitting element connected between a third node and a second power source, the third node connected between the driving transistor and the light emitting element;
a first transistor connected between the third node and a first initializing power line to initialize a voltage of the third node;
a second transistor connected between a data line and the first node and having a gate electrode connected to a first scan line;
a third transistor connected between the gate electrode of the driving transistor and a second initializing power line to initialize a voltage of the gate electrode of the driving transistor;
a fourth transistor connected between the third node and the gate electrode of the driving transistor and having a gate electrode connected to the first scan line; and
a fifth transistor connected between the first node and the first power source and having a gate electrode connected to an emission control line,
wherein the second initializing power line has a voltage greater than a voltage of the first initializing power line, and
wherein:
a first signal is supplied through the first scan line;
a second signal is supplied through the emission control line;
the second transistor is turned on in response to the first signal enabled in a first time period; and
the fifth transistor is turned on in response to the second signal enabled in a second time period,
the second time period does not overlap the first time period.
2. The pixel of claim 1 , further comprising a sixth transistor connected between the third node and the light emitting element and having a gate electrode connected to the emission control line.
3. The pixel of claim 1 , further comprising a capacitor connected between the first power source and the second node.
4. The pixel of claim 1 , wherein the first node is directly connected to the driving transistor, the second transistor, and the fifth transistor.
5. The pixel of claim 1 , wherein the third node is directly connected to the driving transistor and the fourth transistor.
6. The pixel of claim 1 , wherein the first transistor has a gate electrode connected to the first scan line.
7. The pixel of claim 1 , wherein the third transistor has a gate electrode connected to a second scan line different from the first scan line.
8. The pixel of claim 1 , wherein the fifth transistor has a turn-on period that does not overlap a turn-on period of the second transistor.
9. The pixel of claim 1 , wherein the voltage of the first initializing power line is greater than a voltage of the second power source.
10. The pixel of claim 1 , wherein the voltage of the second initializing power line is lower than a voltage of a data signal of the data line.
11. A display device comprising:
pixels connected to scan lines, data lines, and emission control lines;
a scan driver to supply scan signals to the scan lines;
an emission control driver to supply emission control signals to the emission control lines; and
a data driver to supply data signals to the data lines,
one of the pixels comprises:
a driving transistor connected to a first node and having a gate electrode connected to a second node, the first node connected to a first power source;
a light emitting element connected between a third node and a second power source, the third node connected between the driving transistor and the light emitting element;
a first transistor connected between the third node and a first initializing power line to initialize a voltage of the third node;
a second transistor connected between one of the data lines and the first node and having a gate electrode connected to a first one of the scan lines;
a third transistor connected between the gate electrode of the driving transistor and a second initializing power line to initialize a voltage of the gate electrode of the driving transistor;
a fourth transistor connected between the third node and the gate electrode of the driving transistor and having a gate electrode connected to the first one of the scan lines; and
a fifth transistor connected between the first node and the first power source and having a gate electrode connected to one of the emission control lines,
wherein the second initializing power line has a voltage greater than a voltage of the first initializing power line, and
wherein:
a first signal is supplied through the first scan line;
a second signal is supplied through the emission control line;
the second transistor is turned on in response to the first signal enabled in a first time period; and
the fifth transistor is turned on in response to the second signal enabled in a second time period,
the second time period does not overlap the first time period.
12. The display device of claim 11 , wherein the first node is directly connected to the driving transistor, the second transistor, and the fifth transistor.
13. The display device of claim 11 , wherein the third node is directly connected to the driving transistor and the fourth transistor.
14. The display device of claim 11 , wherein the first transistor has a gate electrode connected to the first one of the scan lines.
15. The display device of claim 14 , wherein the third transistor has a gate electrode connected to a second one of the scan lines different from the first one of the scan lines.