Oled ac driving circuit, driving method and display device

Patent metadata

Field	Value
Publication number	US-2016125803-A1
Application number	US-201314366893-A
Country	US
Kind code	A1
Filing date	Nov 1, 2013
Priority date	Jul 25, 2013
Publication date	May 5, 2016
Grant date	—

Abstract

An OLED AC driving circuit, a driving method and a display device are disclosed in the present disclosure. The OLED AC driving circuit includes a light-emitting control unit, a charging unit, a driving unit, a first storage unit, a second storage unit, a first light-emitting unit, a second light-emitting unit, a first voltage control unit and a second voltage control unit. The present disclosure employs the first light-emitting unit and the second light-emitting unit which are connected reversely with each other to make the first light-emitting unit and the second light-emitting unit emit light alternately during two adjacent frames. In one frame, only one light-emitting unit emits light for display while the other one is reversely biased. When the next frame comes, the two units exchange their operating states. The AC driving of the light-emitting units is realized, thus improving the energy utilization efficiency. The cause of the aging of the light-emitting unit is removed completely, and the lifespan of the light-emitting unit is extended largely. The influence of the internal resistance of the lines on the light-emitting current is eliminated, and the display quality of pictures is improved.

First claim

1 - 12 . (canceled)

13 . An OLED AC driving circuit comprising a light-emitting control unit, a charging unit, a driving unit, a first storage unit, a second storage unit, a first light-emitting unit, a second light-emitting unit, a first voltage control unit and a second voltage control unit, wherein
the light-emitting control unit is connected to the driving unit, the second storage unit and the first voltage control unit, and is configured to control the first light-emitting unit or the second light-emitting unit under the control of a light-emitting control signal; the charging unit is connected to the driving unit, the first storage unit, the second storage unit, the first light-emitting unit, the second light-emitting unit and the second voltage control unit, and is configured to charge the first storage unit or the second storage unit under the control of a scan signal and a data signal; the driving unit is connected to the first storage unit, the second storage unit, the first light-emitting unit and the second light-emitting unit, and is configured to drive the first light-emitting unit or the second light-emitting unit to emit light; the first storage unit is connected to the first light-emitting unit, the second light-emitting unit, the driving unit and the charging unit, and is configured to store the data signal or turn on the driving unit; the second storage unit is connected to the first voltage control unit and the driving unit, and is configured to store the data signal or turn on the driving unit; the first light-emitting unit is connected to the second voltage control unit, and is configured to emit light under the control of the first voltage control unit, the second voltage control unit, the charging unit and the driving unit; the second light-emitting unit is connected to the second voltage control unit, and is configured to emit light under the control of the first voltage control unit, the second voltage control unit, the charging unit and the driving unit; the first voltage control unit is connected to the light-emitting control unit and the second storage unit, and is configured to supply power to the second storage unit and the first light-emitting unit; and the second voltage control unit is connected to the charging unit, the first light-emitting unit and the second light-emitting unit, and is configured to supply power to the first storage unit and the second light-emitting unit.

14 . The OLED AC driving circuit of claim 13 , wherein the light-emitting unit comprises a first transistor having a gate configured to receive the light-emitting control signal, a source connected to the first voltage control unit, and a drain connected to the driving unit.

15 . The OLED AC driving circuit of claim 14 , wherein the driving unit comprises a driving transistor having a gate connected to a first terminal of the first storage unit and a first terminal of the second storage unit, and a source and a drain connected to the light-emitting control unit and a second terminal of the first storage unit, respectively.

16 . The OLED AC driving circuit of claim 15 , wherein the charging unit comprises:
a second transistor having a gate configured to receive the scan signal, a source connected to the drain of the driving transistor, and a drain connected to the second voltage control unit; and a third transistor having a gate configured to receive the scan signal, a source configured to receive the data signal, and a drain connected to the gate of the driving transistor.

17 . The OLED AC driving circuit of claim 16 , wherein the first storage unit comprises a first capacitor, and two terminals of the first capacitor are connected to the source of the second transistor and the drain of the third transistor, respectively.

18 . The OLED AC driving circuit of claim 17 , wherein the second storage unit comprises a second capacitor, and two terminals of the second capacitor are connected to the light-emitting control unit and the gate of the driving transistor, respectively.

19 . The OLED AC driving circuit of claim 18 , wherein the first light-emitting unit comprises a first light-emitting device having an anode connected to the drain of the driving transistor and a cathode connected to the second voltage control unit.

20 . The OLED AC driving circuit of claim 19 , wherein the second light-emitting unit comprises a second light-emitting device having a cathode connected to the drain of the driving transistor and an anode connected to the second voltage control unit.

21 . The OLED AC driving circuit of claim 20 , wherein the light-emitting control unit, the charging unit and the driving transistor are N-type transistors or P-type transistors.

22 . A display device comprising the OLED AC driving circuit of claim 13 .

23 . The display device of claim 22 , wherein the light-emitting unit comprises a first transistor having a gate configured to receive the light-emitting control signal, a source connected to the first voltage control unit, and a drain connected to the driving unit.

24 . The display device of claim 23 , wherein the driving unit comprises a driving transistor having a gate connected to a first terminal of the first storage unit and a first terminal of the second storage unit, and a source and a drain connected to the light-emitting control unit and a second terminal of the first storage unit, respectively.

25 . The display device of claim 24 , wherein the charging unit comprises:
a second transistor having a gate configured to receive the scan signal, a source connected to the drain of the driving transistor, and a drain connected to the second voltage control unit; and a third transistor having a gate configured to receive the scan signal, a source configured to receive the data signal, and a drain connected to the gate of the driving transistor.

26 . The display device of claim 25 , wherein the first storage unit comprises a first capacitor, and two terminals of the first capacitor are connected to the source of the second transistor and the drain of the third transistor, respectively; and
the second storage unit comprises a second capacitor, and two terminals of the second capacitor are connected to the light-emitting control unit and the gate of the driving transistor, respectively.

27 . The display device of claim 26 , wherein the first light-emitting unit comprises a first light-emitting device having an anode connected to the drain of the driving transistor and a cathode connected to the second voltage control unit; and
the second light-emitting unit comprises a second light-emitting device having a cathode connected to the drain of the driving transistor and an anode connected to the second voltage control unit.

28 . The display device of claim 27 , wherein the light-emitting control unit, the charging unit and the driving transistor are N-type transistors or P-type transistors.

29 . A driving method of the OLED AC driving circuit of claim 13 , comprising:
charging the first storage unit; controlling the first light-emitting unit to emit light; charging the second storage unit; and controlling the second light-emitting unit to emit light.

30 . The driving method of claim 29 , wherein
said charging the first storage unit comprises:
controlling the scan signal to be at a high level to turn on the charging unit, and controlling the light-emitting control signal to be at a low level to turn off the light-emitting control unit;
controlling the output voltage of the first voltage co

Assignees

• Boe Technology Group Co Ltd
• Chengdu Boe Optoelect Tech Co

Inventors

• Qing Haigang
• Qi Xiaojing

Classifications

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G09G2310/0272

  Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current · CPC title

• G09G2320/043

  Preventing or counteracting the effects of ageing · CPC title

• G09G3/3233 Primary

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

• G09G2300/0852

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