Apparatus for scan driving including scan driving units
A scan driving apparatus, includes a first scan driving unit coupled to a second scan driving unit, the first scan driving unit receives a first start signal, a first clock signal, a second clock signal, and sequentially outputs the first clock signal as a first scan, and outputs the first boost clock signal as a first boost signal, and the second scan driving receives the first clock signal, the second clock signal, a second boost clock signal, and the first scan signal as a second start signal, to sequentially output the second clock signal as a second scan signal, and sequentially outputs the second boost clock signal as a second boost signal.
1. A scan driving apparatus comprising:
a first scan driving unit configured to receive a first start signal, a first clock signal, a second clock signal, and a first boost clock signal, to sequentially output the first clock signal as a first scan signal having a first period in accordance with the first start signal applied in response to the second clock signal, and to sequentially output the first boost clock signal as a first boost signal having the first period, wherein the first scan signal changes from a first logic level to a second logic level at a start time of the first period of the first scan signal, and wherein the first boost signal changes from the first logic level to the second logic level at a start time of the first period of the first boost signal, wherein the start time of the first period of the first boost signal is delayed from the start time of the first period of the first scan signal, and wherein an end time of the first period of the first boost signal is delayed from an end time of the first period of the first scan signal; and
a second scan driving unit coupled to the first scan driving unit, the second scan driving unit configured to receive the first clock signal, the second clock signal, a second boost clock signal, and the first scan signal as a second start signal, to sequentially output the second clock signal as a second scan signal having a second period in accordance with the second start signal applied in response to the first clock signal, and to sequentially output the second boost clock signal as a second boost signal having the second period.
2. The scan driving apparatus of claim 1 , wherein the first scan driving unit comprises:
a scan signal generator configured to receive the first clock signal and the second clock signal and output the first clock signal as the first scan signal in accordance with the first start signal applied by the second clock signal; and
a boost output terminal configured to receive the first boost clock signal and output the first boost clock signal as the first boost signal in accordance with the first start signal applied in response to the second clock signal.
3. The scan driving apparatus of claim 2 , wherein
the scan signal generator of the first scan driving unit comprises:
a first transistor comprising a first terminal for receiving the first clock signal, a gate terminal for receiving the first start signal, and a second terminal for outputting the first scan signal;
a first capacitor coupled between the gate terminal of the first transistor and the second terminal of the first transistor; and
a second transistor comprising a first terminal coupled with the gate terminal of the first transistor, a gate terminal for receiving the second clock signal, and a second terminal for receiving the first start signal, and
the boost output terminal of the first scan driving unit comprises:
a third transistor comprising a first terminal for receiving the first boost clock signal, a gate terminal coupled to the gate terminal of the first transistor, and a second terminal for outputting the first boost clock signal; and
a second capacitor coupled between the gate terminal of the third transistor and the second terminal of the third transistor.
4. The scan driving apparatus of claim 3 , wherein
the scan signal generator of the first scan driving unit further comprises:
a fourth transistor comprising a first terminal coupled with a first power source, a gate terminal, and a second terminal coupled with the second terminal of the first transistor; and
a fifth transistor comprising a first terminal coupled with the gate terminal of the fourth transistor, a gate terminal for receiving a first initial signal, and a second terminal coupled with a second power source, wherein the first power source is configured to generate a higher voltage level than the second power source, and
the boost output terminal of the first scan driving unit further comprises
a sixth transistor comprising a first terminal coupled with the first power source, a gate terminal coupled with the first terminal of the fifth transistor, and the second terminal coupled with the second terminal of the third transistor.
5. The scan driving apparatus of claim 4 , wherein the first initial signal becomes a pulse of an activation level before the first start signal becomes a pulse of an activation level.
6. The scan driving apparatus of claim 4 , wherein the scan signal generator of the first scan driving unit further comprises:
a seventh transistor comprising a first terminal coupled with the first power source, a gate terminal for receiving the first start signal, and a second terminal coupled with the first terminal of the fifth transistor; an eighth transistor comprising a first terminal coupled with the first power source, a second terminal, and a gate terminal coupled with the second terminal of the seventh transistor; and
a ninth transistor comprising a first terminal coupled with the second terminal of the eighth transistor, a gate terminal coupled with the gate terminal of the eighth transistor, and a second terminal coupled with the gate terminal of the first transistor.
7. The scan driving apparatus of claim 1 , wherein the second scan driving unit comprises:
a scan signal generator for receiving the first clock signal, and the second clock signal, and for outputting the second clock signal as the second scan signal in accordance with the second start signal applied in response to the first clock signal; and
a boost output terminal for receiving the second boost clock signal and for outputting the second boost clock signal as the second boost signal in accordance with the second start signal applied in response to the first clock signal.
8. The scan driving apparatus of claim 7 , wherein
the scan signal generator of the second scan driving unit comprises:
a tenth transistor comprising a first terminal for receiving the second clock signal, a gate terminal for receiving the second start signal according to the first clock signal, and a second terminal for outputting the second scan signal;
a third capacitor coupled with the gate terminal and the second terminal of the tenth transistor; and
an eleventh transistor comprising a first terminal coupled with the gate terminal of the tenth transistor, a gate terminal for receiving the first clock signal, and the second terminal for receiving the second start signal, and
the boost output terminal of the second scan driving unit comprises:
a twelfth transistor comprising a first terminal for receiving the second boost clock signal, a gate terminal for receiving the second start signal applied by the first clock signal, and a second terminal configured to output the second boost clock signal; and
a fourth capacitor coupled with the gate terminal and the second terminal of the twelfth transistor.
9. The scan driving apparatus of claim 8 , wherein
the scan signal generator of the second scan driving unit further comprises:
a thirteenth transistor comprising a first terminal coupled with the first power source and a second terminal coupled to the second terminal of the tenth transistor; and
a fourteenth transistor comprising a first terminal coupled with the gate terminal of the thirteenth transistor, a gate terminal for receiving a second initial signal, and a second terminal coupled with the second power source; and
the boost output terminal of the second scan driving unit further comprises
a fifteenth transistor comprising a first terminal coupled with the first power source, a gate terminal coupled with the first terminal of the fourteenth transistor, and a second terminal coupled with the second terminal of the twelfth transistor.
10. The scan driving apparatus of claim 9 , wherein the second initial signal becomes a pulse of an activation level before the second start signal becomes a pulse of an activation level.
11. The scan driving apparatus of claim 9 , wherein the scan signal generator of the second scan driving unit further comprises:
a sixteenth transistor comprising a first terminal coupled with the first power source, a gate terminal for receiving the second start signal, and a second terminal coupled with the first terminal of the fourteenth transistor;
a seventeenth transistor comprising a first terminal coupled with the first power source, a second terminal, and a gate terminal coupled with the second terminal of the sixteenth transistor; and
an eighteenth transistor comprising a first terminal coupled with the second terminal of the seventeenth transistor, a gate terminal coupled with the gate terminal of the seventeenth transistor, and a second terminal coupled with the gate terminal of the tenth transistor.
12. The scan driving apparatus of claim 1 , wherein, the first scan signal is a frame start signal which is applied to display an image of one frame.
13. The scan driving apparatus of claim 1 , wherein the first boost clock signal is delayed from the first clock signal by a first time period.
14. The scan driving apparatus of claim 13 , wherein the first period is set by a user.