ELECTRONIC CIRCUIT, METHOD OF DRIVING ELECTRONIC CIRCUIT, ELECTRO-OPTICAL DEVICE, AND ELECTRONIC APPARATUS

• US 20060231740A1
• Filed: 04/14/2006
• Published: 10/19/2006
• Est. Priority Date: 04/19/2005
• Status: Active Grant

• Current Assignee: Element Capital Commercial Company Pte. Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: KASAI, Toshiyuki
• Granted Patent: US 7,329,849 B2
• Time in Patent Office: Days
• US Class Current: 250/214.100
• 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 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3291 in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements

Abstract

There is provided a method of driving an electronic circuit. The electronic circuit includes a light-emitting element that is interposed between a first electric supply line and a second electric supply line having different potentials and emits light by the supply of a current, a storage capacitor that holds a voltage between a first electrode and a second electrode, and a driving transistor that is interposed between the first electric supply line and the second electric supply line and has a gate terminal connected to the first electrode of the storage capacitor. The method includes: for a first period, applying a data potential according to a gray-scale level designated for the light-emitting element to the second electrode of the storage capacitor while electrically connecting an initialization wiring line supplied with an initialization potential to the first electrode of the storage capacitor; and for a second period subsequent to the first period, electrically connecting the second electrode of the storage capacitor to a source terminal of the driving transistor.

Claims

1. A method of driving an electronic circuit, the electronic circuit including a light-emitting element that is interposed between a first electric supply line and a second electric supply line having different potentials and emits light by the supply of a current, a storage capacitor that holds a voltage between a first electrode and a second electrode, and a driving transistor that is interposed between the first electric supply line and the second electric supply line and has a gate terminal connected to the first electrode of the storage capacitor, the method comprising:

for a first period, applying a data potential according to a gray-scale level designated for the light-emitting element to the second electrode of the storage capacitor while electrically connecting an initialization wiring line supplied with an initialization potential to the first electrode of the storage capacitor; and

for a second period subsequent to the first period, electrically connecting the second electrode of the storage capacitor to a source terminal of the driving transistor.

2. The method of driving an electronic circuit according to claim 1,

wherein the initialization potential is set to a level which allows the driving transistor to be turned off.

3. An electronic circuit comprising:

a light-emitting element that is interposed between a first electric supply line and a second electric supply line having different potentials and emits light by the supply of a current;

a storage capacitor that holds a voltage between a first electrode and a second electrode;

a driving transistor that is interposed between the first electric supply line and the second electric supply line and has a gate terminal connected to the first electrode of the storage capacitor;

a selecting switching element that switches an electrically conductive state and an electrically non-conductive state between a data line and the second electrode of the storage capacitor, the data line being supplied with a data potential according to a gray-scale level designated for the light-emitting element;

a first switching element that switches an electrically conductive state and an electrically non-conductive state between a first terminal and a second terminal, the first terminal being connected to an initialization wiring line supplied with an initialization potential, the second terminal being connected to the first electrode of the storage capacitor; and

a second switching element that switches an electrically conductive state and an electrically non-conductive state between a first terminal and a second terminal, the first terminal being connected to the second electrode of the storage capacitor, the second terminal being connected to a source terminal of the driving transistor.

4. The electronic circuit according to claim 3,

wherein the initialization potential is set to a level which allows the driving transistor to be turned off.

5. The electronic circuit according to claim 3,

wherein each of the driving transistor, the selecting switching element, the first switching element, and the second switching element is composed of an n-channel-type transistor.

6. The electronic circuit according to claim 3,

wherein the selecting switching element is turned on for a part or all of a first period in accordance with a scanning signal supplied to the corresponding selecting switching element and turned off for a second period subsequent to the first period,

the first switching element is turned on for the first period in accordance with a first control signal supplied to the corresponding first switching element and turned off for the second period, and

the second switching element is turned off for the first period in accordance with a second control signal supplied to the corresponding second switching element and turned on for the second period.

7. The electronic circuit according to claim 6,

wherein the first switching element is turned on for both an initialization period and a writing period right after the initialization period, all of which are included in the first period, and

the selecting switching element is turned off for the initialization period and turned on for the writing period.

8. The electronic circuit according to claim 6,

wherein the scanning signal is supplied to the selecting switching element and to the first switching element as the first control signal.

9. The electronic circuit according to claim 6,

wherein each of the first switching element and the second switching element is composed of a different channel type transistor, and

the first control signal is supplied to the first switching element and to the second switching element as the second control signal.

10. The electronic circuit according to claim 6,

wherein each of the second switching element and the selecting switching element is composed of a different channel type transistor, and

the scanning signal is supplied to the selecting switching element and to a gate terminal of the second switching element as the second control signal.

11. The electronic circuit according to claim 6,

wherein the second switching element is composed of a different channel type transistor from the selecting switching element and the first switching element, and

the scanning signal is supplied to the first switching element as the first control signal and to the second switching element as the second control signal.

12. The electronic circuit according to claim 6,

wherein the scanning signal is supplied to the selecting switching element and to the initialization writing line as the initialization potential.

13. The electronic circuit according to claim 6,

wherein the second control signal is supplied to the second switching element and to the initialization wiring line as the initialization potential.

14. An electro-optical device comprising:

a plurality of the electronic circuits according to claim 3, which are disposed in a matrix;

a driving circuit that drives each of the electronic circuits so as to allow the light-emitting element to emit light.

15. The electro-optical device according to claim 14,

wherein the selecting switching element of each electronic circuit is turned on for a part or all of a first period in accordance with a scanning signal supplied from the driving circuit and turned off for a second period subsequent to the first period, and

a scanning signal, which is supplied from the driving circuit to a selecting switching element of one electronic circuit, is supplied to an initialization wiring line of another electronic circuit as the initialization potential.

16. An electronic apparatus comprising the electro-optical device according to claim 14.