Electronic circuit, optoelectronic device, method for driving optoelectronic device, and electronic apparatus

• US 20080068361A1
• Filed: 10/30/2007
• Published: 03/20/2008
• Est. Priority Date: 05/31/2002
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Miyazawa, Takashi
• Granted Patent: US 8,094,144 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G09G 2300/043 Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• 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 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: G09G 3/325 the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver

Abstract

An electronic circuit, an electronic device, and an electronic apparatus are provided that are capable of display with good quality and reducing operation delay, and a method to drive the electronic circuit. First and second switching transistors are turned on and an operation voltage Vdx and a data-current Idata are transmitted to a holding capacitor. The conduction state of a driving transistor is set according to an electrical-charge amount corresponding to the data-current Idata held in the holding capacitor and a current that passes the driving transistor is transmitted to an organic EL element. Then, a first switch is turned off, a second switch and the second switching transistor are turned on, and a reset voltage Vr is transmitted to the holding capacitor, whereby the driving transistor is turned off and the organic EL element stops emitting light.

Claims

1. An electronic circuit for driving an electronic element, comprising:

a first transistor;

a holding element that is connected to a gate of the first transistor, the holding element accumulating a first electrical charge whose amount corresponds to a current level of a current signal that flows through the first transistor as a current during a first period, and the holding element accumulating a second electrical charge whose amount corresponds to a voltage level of a voltage signal that is supplied to the holding element during a second period different from the first period; and

a driving voltage or a driving current whose level corresponds to the first electrical charge being supplied to the electronic element through the first transistor.

2. The electronic circuit according to claim 1,

the voltage signal being set so that a conduction state of the first transistor determined based on the second electrical charge is lower than a conduction state of the first transistor determined based on the first electrical charge.

3. The electronic circuit according to claim 1,

the first transistor being in a substantial off-state during a period in which the second electrical charge is maintained to the holding element.

4. An electro-optical device, comprising:

a plurality of data lines;

a plurality of scan lines; and

a plurality of electronic circuits, each of the plurality of electronic circuits being as claimed in claim 1,

each of the plurality of electronic circuits including an electronic element, and

the electronic elements functioning as an electro-optical element.

5. An electronic circuit for driving an electronic element, comprising:

a first transistor; and

a holding element,

wherein a first conduction state of the first transistor being set by a current signal that flows through the first transistor,

a second conduction state of the first transistor being set by a voltage signal that is supplied to the holding element, and

a conduction state of the first transistor changing from the first conduction state to the second conduction state by the voltage signal.

6. The electronic circuit according to claim 5,

the holding element being connected to a gate of the first transistor.

7. An electro-optical device comprising:

a plurality of data lines;

a plurality of scan lines; and

a plurality of electronic circuits, each of the plurality of electronic circuits being as claimed in claim 5,

each of the plurality of electronic circuits including the electronic element, and

the electronic elements functioning as an electro-optical element.

8. The electronic circuit according to claim 5,

the second conduction state being lower than the first conduction state.