DISPLAY DEVICE AND DRIVING METHOD OF DISPLAY DEVICE

• US 20100245219A1
• Filed: 06/11/2010
• Published: 09/30/2010
• Est. Priority Date: 09/16/2005
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: SHISHIDO, Hideaki
• Granted Patent: US 8,743,030 B2
• Time in Patent Office: Days
• US Class Current: 345/80
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than 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 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/0256 with the purpose of reversing the voltage across a light emitting or modulating element within a pixel
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 2320/0223 Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 3/3241 the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• CPC Class Codes: H01L 27/13 combined with thin-film or thick-film passive components

Abstract

One feature of the present invention includes first to third steps of holding a voltage, corresponding to a difference between a voltage applied to a first power supply line and a threshold voltage of a first transistor, between both electrodes of first and second storage capacitors; holding a voltage, corresponding to a difference between a voltage applied to the first power supply line and a gate-source voltage of the first transistor, which is necessary to supply a light-emitting element with a current equivalent to a video signal current inputted into a signal line, between both the electrodes of the second storage capacitor; and applying a voltage based on the voltage held in the first and second storage capacitors in the first and second steps to a gate electrode of the first transistor; therefore, a current is supplied to the light-emitting element through the first transistor.

Claims

1. A display device comprising:

a first FPC and a second FPC connected to a same surface of a substrate,

wherein the substrate is provided with a pixel portion between the first FPC and the second FPC,

wherein the pixel portion comprises a first transistor comprising a-InGaZnO, and

wherein the first transistor is formed over the substrate.

2. The display device according to claim 1, wherein an IC chip is provided over each of the first FPC and the second FPC.

3. The display device according to claim 1, wherein the IC chip comprises a signal line driver circuit.

4. The display device according to claim 1, wherein the IC chip comprises a scanning line driver circuit.

5. The display device according to claim 1,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the third transistor, a second electrode of the fourth transistor, and a first electrode of the second storage capacitor,

wherein a first electrode of the first transistor is electrically connected to the first power supply line

wherein a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein the gate electrode of the first transistor is directly electrically connected to a first electrode of the second transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, and a second electrode of the third transistor is electrically connected to a first electrode of the first storage capacitor,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the first storage capacitor is electrically connected to the capacitor line,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

6. The display device according to claim 1,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the second transistor, a second electrode of the fourth transistor, and a first electrode of the first storage capacitor;

a first electrode of the first transistor is electrically connected to the first power supply line; and

a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, a first electrode of the third transistor is electrically connected to a second electrode of the first storage capacitor and a first electrode of the second storage capacitor, and a second electrode of the third transistor is electrically connected to the capacitor line, wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

7. A display device comprising:

a first FPC and a second FPC connected to a same surface of a substrate,

wherein the substrate is provided with a pixel portion between the first FPC and the second FPC,

wherein the pixel portion comprises a first transistor comprising In, Ga, Zn and O, and

wherein the first transistor is formed over the substrate.

8. The display device according to claim 7, wherein an IC chip is provided over each of the first FPC and the second FPC.

9. The display device according to claim 7, wherein the IC chip comprises a signal line driver circuit.

10. The display device according to claim 7, wherein the IC chip comprises a scanning line driver circuit.

11. The display device according to claim 7,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the third transistor, a second electrode of the fourth transistor, and a first electrode of the second storage capacitor,

wherein a first electrode of the first transistor is electrically connected to the first power supply line

wherein a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein the gate electrode of the first transistor is directly electrically connected to a first electrode of the second transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, and a second electrode of the third transistor is electrically connected to a first electrode of the first storage capacitor,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the first storage capacitor is electrically connected to the capacitor line,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

12. The display device according to claim 7,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the second transistor, a second electrode of the fourth transistor, and a first electrode of the first storage capacitor;

a first electrode of the first transistor is electrically connected to the first power supply line; and

a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, a first electrode of the third transistor is electrically connected to a second electrode of the first storage capacitor and a first electrode of the second storage capacitor, and a second electrode of the third transistor is electrically connected to the capacitor line,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

13. An electronic book comprising:

a first FPC and a second FPC connected to a same surface of a substrate,

wherein the substrate is provided with a pixel portion between the first FPC and the second FPC,

wherein the pixel portion comprises a first transistor comprising a-InGaZnO, and

wherein the first transistor is formed over the substrate.

14. The electronic book according to claim 13, wherein an IC chip is provided over each of the first FPC and the second FPC.

15. The electronic book according to claim 13, wherein the IC chip comprises a signal line driver circuit.

16. The electronic book according to claim 13, wherein the IC chip comprises a scanning line driver circuit.

17. The electronic book according to claim 13,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the third transistor, a second electrode of the fourth transistor, and a first electrode of the second storage capacitor,

wherein a first electrode of the first transistor is electrically connected to the first power supply line

wherein a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein the gate electrode of the first transistor is directly electrically connected to a first electrode of the second transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, and a second electrode of the third transistor is electrically connected to a first electrode of the first storage capacitor,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the first storage capacitor is electrically connected to the capacitor line,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

18. The electronic book according to claim 13,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the second transistor, a second electrode of the fourth transistor, and a first electrode of the first storage capacitor;

a first electrode of the first transistor is electrically connected to the first power supply line; and

a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, a first electrode of the third transistor is electrically connected to a second electrode of the first storage capacitor and a first electrode of the second storage capacitor, and a second electrode of the third transistor is electrically connected to the capacitor line,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

19. An electronic book comprising:

a first FPC and a second FPC connected to a same surface of a substrate,

wherein the substrate is provided with a pixel portion between the first FPC and the second FPC,

wherein the pixel portion comprises a first transistor comprising In, Ga, Zn and O, and

wherein the first transistor is formed over the substrate.

20. The electronic book according to claim 19, wherein an IC chip is provided over each of the first FPC and the second FPC.

21. The electronic book according to claim 19, wherein the IC chip comprises a signal line driver circuit.

22. The electronic book according to claim 19, wherein the IC chip comprises a scanning line driver circuit.

23. The electronic book according to claim 19,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the third transistor, a second electrode of the fourth transistor, and a first electrode of the second storage capacitor,

wherein a first electrode of the first transistor is electrically connected to the first power supply line

wherein a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein the gate electrode of the first transistor is directly electrically connected to a first electrode of the second transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, and a second electrode of the third transistor is electrically connected to a first electrode of the first storage capacitor,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the first storage capacitor is electrically connected to the capacitor line,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.

24. The electronic book according to claim 19,

wherein the pixel portion further comprises a light-emitting element, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a first storage capacitor, a second storage capacitor, a signal line, a first scanning line, a second scanning line, a third scanning line, a fourth scanning line, a first power supply line, a second power supply line and a capacitor line,

wherein a gate electrode of the first transistor is electrically connected to a first electrode of the second transistor, a second electrode of the fourth transistor, and a first electrode of the first storage capacitor;

a first electrode of the first transistor is electrically connected to the first power supply line; and

a second electrode of the first transistor is electrically connected to a first electrode of the fourth transistor and a first electrode of the fifth transistor,

wherein a gate electrode of the second transistor is electrically connected to the first scanning line, and a second electrode of the second transistor is electrically connected to the signal line,

wherein a gate electrode of the third transistor is electrically connected to the second scanning line, a first electrode of the third transistor is electrically connected to a second electrode of the first storage capacitor and a first electrode of the second storage capacitor, and a second electrode of the third transistor is electrically connected to the capacitor line,

wherein a gate electrode of the fourth transistor is electrically connected to the third scanning line,

wherein a gate electrode of the fifth transistor is electrically connected to the fourth scanning line, and a second electrode of the fifth transistor is electrically connected to a first electrode of the light-emitting element,

wherein a second electrode of the second storage capacitor is electrically connected to the capacitor line, and

wherein a second electrode of the light-emitting element is electrically connected to the second power supply line.