Circuit and method for driving pixel

Patent metadata

Field	Value
Publication number	US-11651737-B2
Application number	US-202217726875-A
Country	US
Kind code	B2
Filing date	Apr 22, 2022
Priority date	Nov 15, 2018
Publication date	May 16, 2023
Grant date	May 16, 2023

Abstract

A circuit for driving a pixel includes a driving transistor having a first end connected to a first node, a control end connected to a second node, and a second end connected to a third node; a writing circuit connected to a first scanning signal and the first node and configured to transmit a data signal to the first node; a reset circuit connected to a second scanning signal and configured to transmit a reference signal to the second node; a compensation circuit connected to a compensation control signal and configured to put through a connection between the second end and the control end of the driving transistor in response to the compensation control signal, wherein the compensation control signal is different from the first scanning signal and the second scanning signal; and an energy storage circuit connected between a first power end and the second node.

First claim

What is claimed is:

1. A circuit for driving a pixel, comprising:
a driving transistor having a first end connected to a first node, a control end connected to a second node, and a second end connected to a third node;
a writing circuit connected to a first scanning signal and the first node and configured to transmit a data signal to the first node;
a first control circuit connected to a light emitting control signal and configured to transmit a first voltage signal to the first node;
a reset circuit connected to a second scanning signal and configured to transmit a reference signal to the second node, wherein the first scanning signal is different from the second scanning signal, and a turning-on level of the second scanning signal is preceding to a turning-on level of the first scanning signal;
a compensation circuit connected to a compensation control signal and configured to put through a connection between the second end and the control end of the driving transistor in response to the compensation control signal, wherein the compensation control signal is different from the first scanning signal and the second scanning signal; wherein in a period, both the first scanning signal and the compensation control signal are at the turning-on level; in another period, the first scanning signal is at a turning-off level, and the compensation control signal is at the turning-on level;
a second control circuit connected to the light emitting control signal and configured to transmit a signal of the third node to a first end of a light emitting element, wherein a second end of the light emitting element is connected to a second voltage signal; and
an energy storage circuit connected between a first power end and the second node.

2. The circuit for driving the pixel according to claim 1 , further comprising:
an initialization circuit connected to a reference signal end and configured to initialize the first end of the light emitting element.

3. The circuit for driving the pixel according to claim 1 , wherein:
the writing circuit comprises a first switching element having a control end connected to a first scanning end, a first end connected to a data signal end, and a second end connected to the first node;
the first control circuit comprises a second switching element having a control end connected to a light emitting control end, a first end connected to the first power end, and a second end connected to the first node;
the reset circuit comprises a third switching element having a control end connected to a second scanning end, a first end connected to a reference signal end, and a second end connected to the second node;
the compensation circuit comprises a fourth switching element having a control end connected to a compensation control signal end, a first end connected to the second end of the driving transistor, and a second end connected to the second node; and
the second control circuit comprises a fifth switching element having a control end connected to the light emitting control end, a first end connected to the third node, and a second end connected to the first end of the light emitting element.

4. A method of driving a pixel applied to a circuit for driving the pixel, comprising:
providing a driving transistor having a first end connected to a first node, a control end connected to a second node, and a second end connected to a third node;
providing a writing circuit connected to a first scanning signal and the first node and configured to transmit a data signal to the first node;
providing a first control circuit connected to a light emitting control signal and configured to transmit a first voltage signal to the first node;
providing a reset circuit connected to a second scanning signal and configured to transmit a reference signal to the second node, wherein the first scanning signal is different from the second scanning signal, and a turning-on level of the second scanning signal is preceding to a turning-on level of the first scanning signal;
providing a compensation circuit connected to a compensation control signal and configured to put through a connection between the second end and the control end of the driving transistor in response to the compensation control signal, wherein the compensation control signal is different from the first scanning signal and the second scanning signal; wherein in a period, both the first scanning signal and the compensation control signal are at the turning-on level; in another period, the first scanning signal is at a turning-off level, and the compensation control signal is at the turning-on level;
providing a second control circuit connected to the light emitting control signal and configured to transmit a signal of the third node to a first end of a light emitting element, wherein a second end of the light emitting element is connected to a second voltage signal;
providing an energy storage circuit connected between a first power end and the second node;
controlling to turn on the reset circuit and the compensation circuit and turn off the writing circuit, the first control circuit, and the second control circuit, so as to make the driving transistor in a bias state;
controlling to turn on the writing circuit and the compensation circuit and turn off the first control circuit and the reset circuit, so as to write the data signal and a threshold voltage of the driving transistor to an energy storage circuit; and
controlling to turn on the first control circuit and the second control circuit and turn off the writing circuit, the reset circuit, and the compensation circuit, so as to control the driving transistor to be turned on by the energy storage circuit to drive a light emitting element to emit light.

5. The method of driving pixel according to claim 4 , further comprising turning on an initialization circuit, so as to initialize the first end of the light emitting element.

6. The method of driving pixel according to claim 4 , wherein:
the writing circuit comprises a first switching element having a control end connected to a first scanning end, a first end connected to a data signal end, and a second end connected to the first node;
the first control circuit comprises a second switching element having a control end connected to a light emitting control end, a first end connected to the first power end, and a second end connected to the first node;
the reset circuit comprises a third switching element having a control end connected to a second scanning end, a first end connected to a reference signal end, and a second end connected to the second node;
the compensation circuit comprises a fourth switching element having a control end connected to a compensation control signal end, a first end connected to the second end of the driving transistor, and a second end connected to the second node; and
the second control circuit comprises a fifth switching element, a control end connected to the light emitting control end, a first end connected to the third node, and a second end connected to the first end of the light emitting element,
wherein the controlling to turn on the reset circuit and the compensation circuit and turn off the writing circuit, the first control circuit and the second control circuit, to make the driving transistor in the bias state, comprises:
the third switching element receiving the second scanning signal to turn on the third switching element, and transmitting the reference signal to the second node; and
the fourth switching element receiving the compensation control signal to turn on the fourth switching element, and putting through the connection between the second end and the control end of the driving transistor; and
the controlling to turn on the writing circuit and the compensation circu

Assignees

• Boe Technology Group Co Ltd

Inventors

• Wang Tieshi
• Gao Xueling
• Xu Zhiqiang
• Yang Chengchung
• Liu Haoran

Classifications

• G09G3/3233 Primary

  with pixel circuitry controlling the current through the light-emitting element · CPC title

• G09G3/3258 Primary

  with pixel circuitry controlling the voltage across the light-emitting element · CPC title

• G09G3/3266

  Details of drivers for scan electrodes · CPC title

• G09G2300/0819

  used for counteracting undesired variations, e.g. feedback or autozeroing · CPC title

• G09G2320/045

  Compensation of drifts in the characteristics of light emitting or modulating elements · CPC title