DISPLAY DEVICE AND ELECTRONIC DEVICE HAVING THE SAME

Abstract

A display device includes a phase comparator which compares whether phases of two signals which are input are different from each other or not; a counter circuit which counts the number of the cases where a phase shift is detected in the phase comparator; and a phase shift circuit which can output a signal in which the phase shift is restored by shifting a phase of one of the two signals in accordance with a degree of the number of phase shifts which is counted in the counter circuit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1A and 1B are block diagrams for showing a structure of the invention;

FIG. 2 is an explanatory diagram of a pixel in a display device to which the invention is applied;

FIG. 3A is a diagram showing an example of a phase comparator of the invention, and FIGS. 3B and 3C are timing charts showing examples of a phase comparator of the invention;

FIG. 4A is a diagram showing an example of a phase comparator of the invention, and FIGS. 4B and 4C are timing charts showing examples of a phase comparator of the invention;

FIG. 5 is a diagram showing an example of a counter circuit of the invention;

FIG. 6 is a circuit diagram showing an example of a D flip-flop circuit of the invention;

FIG. 7 is a timing chart showing an operation of a counter circuit of the invention;

FIG. 8 is a diagram showing an example of a phase shift circuit of the invention;

FIG. 9 is a timing chart showing an operation of a phase shift circuit of the invention;

FIGS. 10A and 10B are diagrams showing Embodiment Mode 2 of the invention;

FIG. 11 is a timing chart showing Embodiment Mode 2 of the invention;

FIG. 12 is a diagram showing Embodiment Mode 2 of the invention;

FIGS. 13A to 13D are timing charts showing Embodiment Mode 2 of the invention;

FIGS. 14A and 14B are diagrams for showing a configuration of a phase comparator in Embodiment Mode 2 of the invention;

FIG. 15 is a block diagram for showing a configuration of Embodiment Mode 2 of the invention;

FIG. 16 is a timing chart for showing a phase comparator in Embodiment Mode 2 of the invention;

FIG. 17 is a timing chart for showing a phase comparator in Embodiment Mode 2 of the invention;

FIG. 18 is a timing chart for showing a phase comparator in Embodiment Mode 2 of the invention;

FIG. 19 is a timing chart for showing a phase comparator in Embodiment Mode 2 of the invention;

FIG. 20 is a timing chart for showing a phase comparator in Embodiment Mode 2 of the invention;

FIGS. 21A to 21H are views showing examples of an electronic device to which the invention is applied; and

FIG. 22A is a diagram showing a conventional example, and FIGS. 22B and 22C are timing charts showing conventional examples.

Claims

1. A display device comprising: a gate signal line;a source signal line;a phase comparator;a counter circuit; anda phase shift circuit,wherein the phase comparator compares a phase of a signal output into the gate signal line and a phase of a signal output into the source signal line;wherein the counter circuit counts the number of signals output from the phase comparator; andwherein the phase shift circuit shifts the phase of the signal output into the gate signal line in accordance with a signal output from the counter circuit.

2. The display device according to claim 1, wherein the phase comparator includes a logic circuit.

3. The display device according to claim 1, wherein the counter circuit includes a flip-flop circuit and a plurality of logic circuits which output a signal in accordance with a signal output from the flip-flop circuit.

4. The display device according to claim 2, wherein the counter circuit includes a flip-flop circuit and a plurality of logic circuits which output a signal in accordance with a signal output from the flip-flop circuit.

5. The display device according to claim 1, wherein the phase shift circuit includes a shift register circuit which shifts the phase of the signal output into the gate signal line and an analog switch provided in each stage of the shift register circuit, and on/off of the analog switch is switched in accordance with the number of signals counted in the counter circuit.

6. The display device according to claim 2, wherein the phase shift circuit includes a shift register circuit which shifts the phase of the signal output into the gate signal line and an analog switch provided in each stage of the shift register circuit, and on/off of the analog switch is switched in accordance with the number of signals counted in the counter circuit.

7. The display device according to claim 3, wherein the phase shift circuit includes a shift register circuit which shifts the phase of the signal output into the gate signal line and an analog switch provided in each stage of the shift register circuit, and on/off of the analog switch is switched in accordance with the number of signals counted in the counter circuit.

8. The display device according to claim 4, wherein the phase shift circuit includes a shift register circuit which shifts the phase of the signal output into the gate signal line and an analog switch provided in each stage of the shift register circuit, and on/off of the analog switch is switched in accordance with the number of signals counted in the counter circuit.

9. A display device comprising: a gate signal line;a source signal line;a phase comparator;a first counter circuit;a second counter circuit;a first phase shift circuit; anda second phase shift circuit,wherein a first signal and a second signal are output into the gate signal line;wherein a video signal is output into the source signal line;wherein the phase comparator compares a phase of the first signal with a phase of the video signal and compares a phase of the second signal with the phase of the video signal;wherein the first counter circuit counts the number of signals which are output by comparing the phase of the first signal with the phase of the video signal in a signal output from the phase comparator;wherein the second counter circuit counts the number of signals which are output by comparing the phase of the second signal with the phase of the video signal in the signal output from the phase comparator;wherein the first phase shift circuit shifts the phase of the first signal based on a signal output from the first counter circuit; andwherein the second phase shift circuit shifts the phase of the second signal based on a signal output from the second counter circuit.

10. The display device according to claim 9, wherein the phase comparator includes a logic circuit and a flip-flop circuit.

11. The display device according to claim 9, wherein the first counter circuit and the second counter circuit includes a flip-flop circuit and a plurality of logic circuits which output a signal in accordance with a signal output from the flip-flop circuit.

12. The display device according to claim 10, wherein the first counter circuit and the second counter circuit includes a flip-flop circuit and a plurality of logic circuits which output a signal in accordance with a signal output from the flip-flop circuit.

13. The display device according to claim 9, wherein the first phase shift circuit includes a first shift register circuit for shifting a phase of the first signal which is output into the gate signal line and a first analog switch provided in each stage of the first shift register circuit;wherein the second phase shift circuit includes a second shift register circuit for shifting a phase of the second signal which is output into the gate signal line and a second analog switch provided in each stage of the second shift register circuit;wherein on/off of the first analog switch is switched in accordance with the number of signals counted in the first counter circuit; andwherein on/off of the second analog switch is switched in accordance with the number of signals counted in the second counter circuit.

14. The display device according to claim 10, wherein the first phase shift circuit includes a first shift register circuit for shifting a phase of the first signal which is output into the gate signal line and a first analog switch provided in each stage of the first shift register circuit;wherein the second phase shift circuit includes a second shift register circuit for shifting a phase of the second signal which is output into the gate signal line and a second analog switch provided in each stage of the second shift register circuit;wherein on/off of the first analog switch is switched in accordance with the number of signals counted in the first counter circuit; andwherein on/off of the second analog switch is switched in accordance with the number of signals counted in the second counter circuit.

15. The display device according to claim 11, wherein the first phase shift circuit includes a first shift register circuit for shifting a phase of the first signal which is output into the gate signal line and a first analog switch provided in each stage of the first shift register circuit;wherein the second phase shift circuit includes a second shift register circuit for shifting a phase of the second signal which is output into the gate signal line and a second analog switch provided in each stage of the second shift register circuit;wherein on/off of the first analog switch is switched in accordance with the number of signals counted in the first counter circuit; andwherein on/off of the second analog switch is switched in accordance with the number of signals counted in the second counter circuit.

16. The display device according to claim 12, wherein the first phase shift circuit includes a first shift register circuit for shifting a phase of the first signal which is output into the gate signal line and a first analog switch provided in each stage of the first shift register circuit;wherein the second phase shift circuit includes a second shift register circuit for shifting a phase of the second signal which is output into the gate signal line and a second analog switch provided in each stage of the second shift register circuit;wherein on/off of the first analog switch is switched in accordance with the number of signals counted in the first counter circuit; andwherein on/off of the second analog switch is switched in accordance with the number of signals counted in the second counter circuit.

17. A display device comprising: a pixel;a first signal line for outputting a first signal having a first phase to the pixel;a second signal line for outputting a second signal having a second phase to the pixel;a phase comparator for comparing the first phase and the second phase, and for outputting a third signal;a counter circuit for counting the number of the third signal, and outputting a fourth signal in accordance with the number of the third signal; anda phase shift circuit for shifting a phase of the first signal based on the fourth signal.

18. The display device according to claim 17, wherein the first signal line is a gate line for being supplied a scan signal, and the second signal line is a source line for being supplied a video signal.

19. The display device according to claim 17, wherein the phase comparator includes a logic circuit.

20. The display device according to claim 18, wherein the phase comparator includes a logic circuit.

21. The display device according to claim 17, wherein the counter circuit includes a flip-flop circuit outputting a signal, and a plurality of logic circuits which output a signal in accordance with the signal output from the flip-flop circuit.

22. The display device according to claim 18, wherein the counter circuit includes a flip-flop circuit outputting a signal, and a plurality of logic circuits which output a signal in accordance with the signal output from the flip-flop circuit.

23. The display device according to claim 19, wherein the counter circuit includes a flip-flop circuit outputting a signal, and a plurality of logic circuits which output a signal in accordance with the signal output from the flip-flop circuit.

24. The display device according to claim 20, wherein the counter circuit includes a flip-flop circuit outputting a signal, and a plurality of logic circuits which output a signal in accordance with the signal output from the flip-flop circuit.

25. The display device according to claim 17, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

26. The display device according to claim 18, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

27. The display device according to claim 19, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

28. The display device according to claim 20, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

29. The display device according to claim 21, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

30. The display device according to claim 22, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

31. The display device according to claim 23, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

32. The display device according to claim 24, wherein the phase shift circuit includes a shift register circuit which shifts the first phase, and an analog switch provided in the shift register circuit,and wherein an on/off of the analog switch is switched in accordance with the fourth signal.

33. An electronic device provided with the display device according to claim 1.

34. An electronic device provided with the display device according to claim 9.

35. An electronic device provided with the display device according to claim 17.