Stage and organic light emitting display device using the same

• US 10,311,781 B2
• Filed: 05/03/2017
• Issued: 06/04/2019
• Est. Priority Date: 06/17/2016
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Lee, Seung Kyu, Cha, Seung Ji, Ka, Ji Hyun, Kwon, Tae Hoon, Lee, Min Ku, Jeong, Jin Tae
• Primary Examiner(s): Watko, Julie Anne
• Application Number:
  US15/585,425
• Publication Number:
  US 20170365211A1
• Time in Patent Office: 762 Days
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0286 Details of a shift registers arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2330/02 Details of power systems and of start or stop of display operation
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3266 Details of drivers for scan electrodes
• CPC Class Codes: G09G 3/3275 Details of drivers for data electrodes

Abstract

A stage includes an output, an input, signal processors, and a stabilizer. The output supplies a voltage of a first or second power source to an output terminal based on voltages of first and second nodes. The input controls voltages of third and fourth nodes based on signals to a first and second input terminals. A first signal processor controls the voltage of the first node based on the voltage of the second node. A second signal processor is connected to a fifth node and controls the voltage of the first node based on a signal to a third input terminal. A third signal processor controls the voltage of the fourth node based on the voltage of the third node and the signal to the third input terminal. The stabilizer is connected between the second signal processor and input to control voltage drop widths of the third and fourth nodes.

Claims

1. A stage, comprising:

an output to supply a voltage of a first power source or a second power source to an output terminal based on voltages of a first node and a second node;

an input to control voltages of a third node and a fourth node based on signals supplied to a first input terminal and a second input terminal;

a first signal processor to control the voltage of the first node based on the voltage of the second node;

a second signal processor, connected to a fifth node, to control the voltage of the first node based on a signal supplied to a third input terminal;

and

a first stabilizer connected between the second signal processor and the input to control voltage levels of the third node and the fourth node to be not below the voltage of the second power source.

2. The stage as claimed in claim 1, wherein

the first power source has a voltage being higher than the voltage of

the second power source.

3. The stage as claimed in claim 1, wherein the first input terminal is to receive an output signal of a previous stage or a start pulse.

4. The stage as claimed in claim 3, wherein the output signal of the previous stage or the start pulse supplied to the first input terminal overlaps a clock signal supplied to the second input terminal at least once.

5. The stage as claimed in claim 1, wherein:

the second input terminal is to receive a first clock signal, and

the third input terminal is to receive a second clock signal.

6. The stage as claimed in claim 5, wherein:

the first clock signal and the second clock signal have a same period, and

the second clock signal is shifted from the first clock signal by a half period.

7. The stage as claimed in claim 1, wherein the first stabilizer includes:

a first transistor connected between the third node and the fifth node and having a gate electrode connected to the second power source; and

a second transistor connected between the second node and the fourth node and having a gate electrode connected to the second power source.

8. The stage as claimed in claim 1, wherein the input includes:

a seventh transistor connected between the first input terminal and the fourth node and having a gate electrode connected to the second input terminal;

an eighth transistor connected between the third node and the second input terminal and having a gate electrode connected to the fourth node; and

a ninth transistor connected between the third node and the second power source and having a gate electrode connected to the second input terminal.

9. The stage as claimed in claim 1, wherein the output includes:

a tenth transistor connected between the first power source and the output terminal and having a gate electrode connected to the first node; and

an eleventh transistor connected between the second power source and the output terminal and having a gate electrode connected to the second node.

10. The stage as claimed in claim 1, wherein the first signal processor includes:

a twelfth transistor connected between the first power source and the first node and having a gate electrode connected to the second node; and

a third capacitor connected between the first power source and the first node.

11. The stage as claimed in claim 1, wherein the second signal processor includes:

a first capacitor connected between the second node and third input terminal;

a second capacitor having a first terminal connected to the fifth node;

a fifth transistor connected between a second terminal of the second capacitor and the first node and having a gate electrode connected to the third input terminal; and

a sixth transistor connected between the second terminal of the second capacitor and the third input terminal and having a gate electrode connected to the fifth node.

12. The stage as claimed in claim 1, further comprising a third signal processor to control the voltage of the fourth node based on the voltage of the third node and the signal supplied to the third input terminal, wherein:

the third signal processor includes a thirteenth transistor and a fourteenth transistor serially connected between a first power source and the fourth node,

a gate electrode of the thirteenth transistor is connected to the third node, and

a gate electrode of the fourteenth transistor is connected to the third input terminal.

13. The stage as claimed in claim 1, further comprising:

a second stabilizer connected to the first power source, the first node, and the third input terminal to uniformly maintain the voltage of the second node in a period in which the voltage of the first power source is to be output to the output terminal.

14. The stage as claimed in claim 13, wherein the second stabilizer includes:

a third transistor connected between the first power source and a sixth node and having a gate electrode connected to the first node;

a fourth transistor connected between the sixth node and the third input terminal and having a gate electrode connected to the second node; and

a first capacitor connected between the second node and the sixth node.

15. The stage as claimed in claim 14, wherein the second signal processor includes:

a second capacitor having a first terminal connected to the fifth node;

a fifth transistor connected between a second terminal of the second capacitor and the first node and having a gate electrode connected to the third input terminal; and

a sixth transistor connected between the second terminal of the first capacitor and the third input terminal and having a gate electrode connected to the fifth node.

16. An organic light emitting 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;

a data driver to supply data signals to the data lines; and

an emission driver including a plurality of stages to supply emission control signals to the emission control lines, wherein each of the stages includes;

an output to supply a voltage of a first power source or a second power source to an output terminal based on voltages of a first node and a second node;

an input to control voltages of a third node and a fourth node based on signals supplied to a first input terminal and a second input terminal;

a first signal processor to control the voltage of the first node based on the voltage of the second node;

a second signal processor, connected to a fifth node, to control the voltage of the first node based on a signal supplied to a third input terminal;

and

a first stabilizer connected between the second signal processor and the input to control voltage levels of the third node and the fourth node to be not below the voltage of the second power source.

17. The organic light emitting display device as claimed in claim 16, wherein:

the first power source has a voltage being higher than the voltage of

the second power source, and

the voltage of the first power source supplied to the output terminal is an emission control signal.

18. The organic light emitting display device as claimed in claim 16, wherein:

the first input terminal is to receive an output signal of a previous stage or a start pulse,

the second input terminal of a jth (j is an odd number or an even number) stage is to receive a first clock signal and the third input terminal of the jth stage is to receive a second clock signal, and

the second input terminal of a (j+1)th stage is to receive the second clock signal and the third input terminal of the (j+1)th stage is to receive the first clock signal.

19. The organic light emitting display device as claimed in claim 16, wherein the first stabilizer includes:

a first transistor connected between the third node and the fifth node and having a gate electrode connected to the second power source; and

a second transistor connected between the second node and the fourth node and having a gate electrode connected to the second power source.

20. The organic light emitting display device as claimed in claim 16, further comprising:

a second stabilizer connected to the first power source, the first node, and the third input terminal to uniformly maintain the voltage of the second node in a period in which the voltage of the first power source is output to the output terminal, wherein the second stabilizer includes;

a third transistor connected between the first power source and a sixth node and having a gate electrode connected to the first node;

a fourth transistor connected between the sixth node and the third input terminal and having a gate electrode connected to the second node; and

a first capacitor connected between the second node and the sixth node.