Stage circuit and organic light emitting display device using the same
An organic light emitting display device having a stage circuit capable of creating a scan signal and a light emitting control signal. The stage circuit includes a control unit controlling a first node and a second node corresponding to signals of a first input terminal, a third input terminal, and a fourth input terminal, a first output unit supplying a light emitting control signal to a second output terminal corresponding to voltages at the first node and the second node, and a second output unit supplying a scan signal having different polarity than that of the light emitting control signal to a first output terminal corresponding to a signal of a second input terminal and voltages at the first node and the second node.
1. A stage circuit comprising:
a control unit controlling voltage at first node and a second node in response to a first clock signal input to a first input terminal, an input control signal input to a third input terminal, and a scan signal of a previous stage or a start signal input to a fourth input terminal;
a first output unit supplying a light emitting control signal to a second output terminal in direct response to the voltages at the first node and the second node; and
a second output unit having a second input terminal, the second output unit supplying a scan signal having different polarity than that of the light emitting control signal to a first output terminal corresponding to a second clock signal input to the second input terminal and in direct response to the voltages at the first node and the second node, wherein the first output unit includes:
a first transistor connected between a first power supply and the second output terminal, and having a gate electrode connected to the second node;
a second transistor connected between the second output terminal and a second power supply having voltage set lower than that of the first power supply, and having a gate electrode connected to the first node; and
a first capacitor connected between the second output terminal and the first node, and the second output unit includes:
a third transistor connected between the first power supply and the first output terminal, and having a gate electrode connected to the first node;
a fourth transistor connected between the first output terminal and the second input terminal, having a gate electrode connected to the second node; and
a second capacitor connected between the first output terminal and the second node.
2. The stage circuit according to claim 1 , wherein the first clock signal and the second clock signal have the same cycle, and phases of the first clock signal and the second clock signal do not overlap with each other.
3. The stage circuit according to claim 1 , wherein the start signal is supplied so as to overlap with the first clock signal.
4. The stage circuit according to claim 1 , wherein the phase of the input control signal does not overlap with the phases of the first clock signal and the second clock signal.
5. The stage circuit according to claim 1 , wherein the control unit includes:
a fifth transistor connected between the first power supply and the first node, and having a gate electrode connected to the fourth input terminal;
a sixth transistor connected between the first node and the second power supply having the voltage set lower than that of the first power supply, and having a gate electrode connected to the third input terminal;
a seventh transistor connected between the first power supply and the second node, and having a gate electrode connected to the first node; and
an eighth transistor connected between the second node and the fourth input terminal, having a gate electrode connected to the first input terminal.
6. The stage circuit according to claim 5 , wherein each of the fifth transistor and the seventh transistor consists of a plurality of transistors connected in series with each other.
7. The stage circuit according to claim 1 , further comprising:
a bi-directional driving unit connected between the fourth input terminal and a seventh input terminal and the control unit.
8. The stage circuit according to claim 7 , wherein the bi-directional driving unit includes:
a ninth transistor connected between the fourth input terminal and the control unit, and turned on when a first bi-directional control signal is supplied;
a tenth transistor connected between the seventh input terminal and the control unit, and turned on when a second bi-directional control signal is supplied.
9. The stage circuit according to claim 7 , wherein the seventh input terminal receives a scan signal of a next stage or the start signal.
10. An organic light emitting display device comprising:
pixels positioned in regions divided by scan lines, light emitting control lines, and data lines;
a data driving unit supplying data signals to the data lines; and
a scan/light emitting driving unit including a plurality of stages each connected to a scan line and a light emitting control line in order to supply scan signals to the scan lines and supply light emitting signals to the light emitting control lines,
wherein each stage includes:
a control unit controlling voltages at a first node and a second node corresponding to one of a first clock signal and a second clock signal input to a first input terminal, an input control signal input to a third input terminal, and a scan signal of a previous stage or a start signal input to a fourth input terminal;
a first output unit supplying a light emitting control signal to a second output terminal corresponding to the first node and the second node; and
a second output unit supplying a scan signal having different polarity than that of the light emitting control signal to a first output terminal corresponding to the other one of the first clock signal and the second clock signal input to a second input terminal and voltages at the first node and the second node, such that the first input terminal and the second input terminal of an odd-number-th stage receive the first clock signal and the second clock signal, respectively, and the first input terminal and the second input terminal of an even-number-th stage receive the second clock signal and the first clock signal, respectively,
wherein the third input terminal of a j-th (j=1, 4, 7,. . .) stage receives a first control signal, the third input terminal of a j+1-th stage receives a second control signal, and the third input terminal of a j+2-th stage receives a third control signal,
wherein the light emitting control signal is supplied during a substantially same period of time in one frame period in each of the plurality of stages.
11. The organic light emitting display device according to claim 10 , wherein the first clock signal and the second clock signal have the same cycle, and phases of the first clock signal and the second clock signal do not overlap with each other.
12. The organic light emitting display device according to claim 10 , wherein the first, second, and third control signals have the same cycle, and phases of the first, second, and third control signals do not overlap with one another.
13. The organic light emitting display device according to claim 12 , wherein the phases of the first, second, and third control signals do not overlap with the clock signals supplied to the first input terminal and the second input terminal.
14. The organic light emitting display device according to claim 10 , wherein the first output unit includes:
a first transistor connected between a first power supply and the second output terminal, and having a gate electrode connected to the second node;
a second transistor connected between the second output terminal and a second power supply having voltage set lower than that of the first power supply, and having a gate electrode connected to the first node; and
a first capacitor connected between the second output terminal and the first node.
15. The organic light emitting display device according to claim 10 , wherein the second output unit includes:
a third transistor connected between the first power supply and the first output terminal, and having a gate electrode connected to the first node;
a fourth transistor connected between the first output terminal and the second input terminal, and having a gate electrode connected to the second node; and
a second capacitor connected between the first output terminal and the second node.
16. The organic light emitting display device according to claim 10 , wherein the control unit includes:
a fifth transistor connected between the first power supply and the first node, and having a gate electrode connected to the fourth input terminal;
a sixth transistor connected between the first node and the second power supply having voltage set lower than that of the first power supply;
a seventh transistor connected between the first power supply and the second node, and having a gate electrode connected to the first node; and
an eighth transistor connected between the second node and the fourth input terminal, and having a gate electrode connected to the first input terminal.