Detection circuit, detection method and pixel driving circuit

Patent metadata

Field	Value
Publication number	US-10438542-B2
Application number	US-201515518335-A
Country	US
Kind code	B2
Filing date	Sep 30, 2015
Priority date	Jun 29, 2015
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

A detection circuit, a detection method and a pixel driving circuit are disclosed in the embodiments of the present disclosure. The detection circuit comprises a first detection unit, a second detection unit, a load unit, a light emitting device and a driving unit. The first detection module connected to the driving unit and the load unit. The second detection unit is connected to the light emitting device and the load unit.

First claim

We claim:

1. A detection circuit, comprising:
a first detection unit;
a second detection unit;
a load capacitor;
a light emitting device; and
a driving unit,
wherein the first detection unit is connected to the driving unit and the load capacitor, and the second detection unit is connected to the light emitting device and the load capacitor;
wherein the first detection unit comprises a first switch transistor, a second switch transistor, a third switch transistor and a storage capacitor, and the driving unit comprises a driving transistor, wherein, the first switch transistor has a control electrode connected to a first control line, a first electrode connected to a data line and the load capacitor, and a second electrode connected to a second electrode of the third switch transistor and a first terminal of the storage capacitor; the second switch transistor has a control electrode connected to a second control line, a first electrode connected to a reference power source, and a second electrode connected to a control electrode of the driving transistor and a second terminal of the storage capacitor;
the third switch transistor has a control electrode connected to a third control line, a first electrode connected to a first power source, and a second electrode connected to a first electrode of the driving transistor and the first terminal of the storage capacitor; and
the driving transistor has the control electrode connected to the second terminal of the storage capacitor and a second electrode connected to a first electrode of the light emitting device;
wherein the second detection unit comprises a fourth switch transistor having a control electrode connected to a fourth control line, a first electrode connected to the data line and the first terminal of the load capacitor, and a second electrode connected to the first electrode of the light emitting device.

2. The detection circuit according to claim 1 , wherein the light emitting device has a second electrode connected to a second power source.

3. A pixel driving circuit comprising a pixel compensation circuit and the detection circuit according to claim 2 ,
wherein the pixel compensation circuit is configured to compensate for the driving unit according to characteristic parameters of the driving unit, and compensate for the light emitting device according to characteristic parameters of the light emitting device.

4. The detection circuit according to claim 1 , wherein in a pre-charging phase, a pre-charging voltage is supplied to the load capacitor through the data line; in a first detection phase, the load capacitor is discharged through the first detection unit and the driving unit, so as to detect characteristic parameters of the driving unit; and in a second detection phase, the load capacitor is discharged through the second detection unit and the light emitting device, so as to detect characteristic parameters of the light emitting device.

5. The detection circuit according to claim 4 , wherein the characteristic parameters of the driving unit comprise at least one of a threshold voltage and electron mobility, and the characteristic parameters of the load capacitor comprise at least one of a threshold voltage and electron mobility.

6. A pixel driving circuit comprising a pixel compensation circuit and the detection circuit according to claim 5 ,
wherein the pixel compensation circuit is configured to compensate for the driving unit according to the characteristic parameters of the driving unit, and compensate for the light emitting device according to the characteristic parameters of the light emitting device.

7. A pixel driving circuit comprising a pixel compensation circuit and the detection circuit according to claim 4 ,
wherein the pixel compensation circuit is configured to compensate for the driving unit according to the characteristic parameters of the driving unit, and compensate for the light emitting device according to the characteristic parameters of the light emitting device.

8. A pixel driving circuit comprising a pixel compensation circuit and the detection circuit according to claim 1 ,
wherein the pixel compensation circuit is configured to compensate for the driving unit according to characteristic parameters of the driving unit, and compensate for the light emitting device according to characteristic parameters of the light emitting device.

9. A detection method for use in the detection circuit according to claim 1 , comprising:
in a pre-charging phase, supplying a pre-charging voltage to the load capacitor through a data line;
in a first detection phase, discharging the load capacitor through the first detection unit and the driving unit, so as to detect characteristic parameters of the driving unit; and
in a second detection phase, discharging the load capacitor through the second detection unit and the light emitting device, so as to detect characteristic parameters of the light emitting device.

10. The detection method according to claim 9 , wherein the second detection unit comprises a fourth switch transistor having a control electrode connected to a fourth control line, a first electrode connected to the data line and a first terminal of the load capacitor, and a second electrode connected to a first electrode of the light emitting device; and
discharging the load capacitor through the second detection unit and the light emitting device comprises: turning on the fourth switch transistor and discharging the load unit through the fourth switch transistor and the light emitting device.

Assignees

• Boe Technology Group Co Ltd

Inventors

• Li Yongqian
• Wang Longyan
• Gai Cuili

Classifications

• G09G2320/029

  by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel · CPC title

• G09G2320/045

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

• G09G2300/0861

  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 title

• G09G2300/0852

  being a dynamic memory with more than one capacitor · CPC title

• G09G3/3291 Primary

  in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements · CPC title