Pixel circuit, driving method thereof and display apparatus

Patent metadata

Field	Value
Publication number	US-2016204166-A1
Application number	US-201414775027-A
Country	US
Kind code	A1
Filing date	Nov 28, 2014
Priority date	Aug 26, 2014
Publication date	Jul 14, 2016
Grant date	—

Abstract

Provided is a pixel circuit, a driving method thereof, and a display apparatus. The pixel circuit comprises a display unit ( 10 ) and a touch control unit ( 20 ), wherein a precharging module ( 13 ) in the display unit ( 10 ) is configured to charge a control terminal of a driving transistor (M 2 ), and maintain the state under the effect of a storage capacitor (C); a compensation module ( 14 ) is configured to compensate a data signal and write the compensated data signal into the storage capacitor (C); a power switch module ( 12 ) is configured to input an operating voltage into the driving transistor (M 2 ) after the data signal is written into the storage capacitor (C); the driving transistor (M 2 ) is configured to use the data signal stored in the storage capacitor (C) to drive a light-emitting element ( 11 ) to emit light; an initialization module ( 21 ) in the touch control unit ( 20 ) is configured to initialize a touch control module ( 22 ) while the precharging module ( 13 ) is operating; a touch control module ( 22 ) is configured to collect touch control signals in corresponding regions; a output control module ( 23 ) is configured to close an output path to output the touch control signals collected by the touch control module ( 22 ) while the compensation module ( 14 ) is operating. The pixel circuit can compensate the threshold voltage drift, and integrate a touch control module into the pixel circuit, which can simplify operation and manufacturing process.

First claim

1 . A pixel circuit comprising a display unit and a touch control unit, wherein the display unit comprises a light-emitting element, a driving transistor, a storage capacitor, a power switch module, a precharging module and a compensation module, the precharging module is configured to charge a control terminal of the driving transistor, and maintain the state under the effect of the storage capacitor, so that a conduction state is maintained between the compensation module and the storage capacitor; the compensation module is configured to compensate a data signal and write the compensated data signal into the storage capacitor; the power switch module is configured to input an operating voltage into the driving transistor after the data signal is written into the storage capacitor; the driving transistor is configured to use the data signal stored in the storage capacitor to drive the light-emitting element to emit light;
the touch control unit comprises an initialization module, a touch control module and an output control module, wherein the initialization module is configured to initialize the touch control module while the precharging module is operating; the touch control module is configured to collect touch control signals in corresponding regions; the output control module is configured to close an output path to output the touch control signals collected by the touch control module while the compensation module is operating.

2 . The pixel circuit according to claim 1 , wherein one terminal of the light-emitting element is connected to a grounded terminal, and the other terminal of the light-emitting element is connected to a second terminal of the driving transistor; a first terminal of the driving transistor is connected to a second terminal of the power switch module, and a control terminal of the driving transistor is connected to a first terminal of the storage capacitor; a first terminal of the power switch module is connected to an input terminal for the operating voltage, and a light emitting control signal is inputted into a control terminal of the power switch module; a second terminal of the storage capacitor is connected to the grounded terminal; the precharging module is connected to the second terminal of the power switch module, the control terminal of the driving transistor and a first control signal line; the compensation module is connected to a data signal line, the control terminal of the driving transistor and a second control signal line.

3 . The pixel circuit according to claim 2 , wherein the initialization module is connected to an input terminal of the touch control module, the first control signal line and an initialization signal line; the output control module is connected to an output terminal of the touch control module, the second control signal line and a signal read line,

4 . The pixel circuit according to claim 3 , wherein the touch control module is a photo-sensitive touch control module or a capacitive touch control module.

5 . The pixel circuit according to claim 4 , wherein the touch control module comprises a photo-sensitive transistor and a first capacitor, wherein
a first terminal of the photo-sensitive transistor is connected to a control terminal of the photo-sensitive transistor and a first terminal of the first capacitor, and is connected to the initialization module as the input terminal of the touch control module; a second terminal of the photo-sensitive transistor is connected to a second terminal of the first capacitor, and is connected to the output control module as the output terminal of the touch control module.

6 . The pixel circuit according to claim 3 , wherein the touch control module comprises a first transistor and a second capacitor, wherein
a control terminal of the first transistor is connected to a first terminal of the second capacitor, and is connected to the initialization module as the input terminal of the touch control module, a second terminal of the first transistor is connected to the output control module as the output terminal of the touch control module, a first terminal of the first transistor and a second terminal of the second capacitor are both connected to a common voltage input terminal.

7 . The pixel circuit according to claim 5 , wherein the initialization module is a second transistor, and the output control module is a third transistor.

8 . The pixel circuit according to claim 7 , wherein the compensation module comprises a fourth transistor and a fifth transistor, a first terminal of the fourth transistor is connected to the data signal line, a second terminal of the fourth transistor is connected to a first terminal of the fifth transistor, a control terminal of the fourth transistor is connected to the second control signal line; a second terminal of the fifth transistor is connected to a control terminal of the fifth transistor and connected to the control terminal of the driving transistor.

9 . The pixel circuit according to claim 8 , wherein the precharging module is a sixth transistor, and the power switch module is a seventh transistor.

10 . The pixel circuit according to claim 9 , wherein all the transistors have the same channel type.

11 . The pixel circuit according to claim 9 , wherein the channel type of the seventh transistor is opposite to that of the fourth transistor, a control terminal of the seventh transistor is connected to the second control signal line.

12 . A display apparatus in which is disposed the pixel circuit according to claim 1 .

13 . A driving method of a pixel circuit comprising
a precharging module charging a control terminal of a driving transistor, so that the potential of the control terminal becomes an operating voltage, the state is maintained under the effect of a storage capacitor, a conduction state is maintained between a compensation module and the storage capacitor, and meanwhile an initialization module in an touch control unit initializes a touch control module; a compensation module compensating a data signal, loading the compensated data signal onto the control terminal of the driving transistor and writing the same into the storage capacitor, and meanwhile an output control module in the touch control unit closing an output path to output the touch control signals collected by the touch control unit to a signal read line; turning off the touch control unit while a power switch module is turned on, inputting the operating voltage into the driving transistor, and the driving transistor using the data signal stored in the storage capacitor to drive a light-emitting element to emit light.

14 . The pixel circuit according to claim 6 , wherein the initialization module is a second transistor, and the output control module is a third transistor.

15 . The display apparatus in which is disposed the pixel circuit according to 12 , wherein one terminal of the light-emitting element is connected to a grounded terminal, and the other terminal of the light-emitting element is connected to a second terminal of the driving transistor; a first terminal of the driving transistor is connected to a second terminal of the power switch module, and a control terminal of the driving transistor is connected to a first terminal of the storage capacitor; a first terminal of the power switch module is connected to an input terminal for the operating voltage, and a light emitting control signal is inputted into a control terminal of the power switch module; a second terminal of the storage capacitor is connected to the grounded terminal; the precharging module is connected to the second terminal of th

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Optoelectronics

Inventors

• Yang Shengji

Classifications

• H01L27/323 Primary

  Electricity · mapped topic

• G09G2320/0233

  Improving the luminance or brightness uniformity across the screen · CPC title

• G09G2320/0626

  for control of overall brightness · CPC title

• G06F3/044

  by capacitive means · CPC title

• G06F3/042

  by opto-electronic means · CPC title