Pixel circuit for compensating shift of threshold voltage and thin film transistor backplane

A technology of voltage drift and threshold compensation, which is applied to instruments, static indicators, etc., and can solve problems such as uneven image display and uneven current

CN102820006AActive Publication Date: 2012-12-12BOE TECH GRP CO LTD
11 Cites 5 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2012-12-12

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The embodiment of the invention provides a pixel circuit for compensating shift of a threshold voltage and a thin film transistor backplane, so as to solve the problem of uneven display of an image caused by the shift of the threshold voltage in the prior art. The pixel circuit comprises a driver module and a signal loading module, wherein the driver module comprises a VDD (virtual device driver) signal source, a driver transistor T1, a storage capacitance C1 and an OLED (organic light emitting diode) D1; a grid electrode of the driver transistor T1 is connected with an output end of the signal loading module and drives the OLED D1 to emit light; one end of the storage capacitance C1 is connected with an output end of the VDD signal source, and the other end of the storage capacitance C1 is connected with the grid electrode of the driver transistor T1; the driver module further comprises a p-shaped decaying transistor T2, the grid electrode is connected with a source electrode and is connected with the output end of the VDD signal source, a drain electrode is connected with the source electrode of the driver transistor T1; alternatively, the driver module further comprises a n-shaped decaying transistor T2, the grid electrode is connected with the drain electrode and is connected with the output end of the VDD signal source, and the source electrode is connected with that of the driver transistor T1.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of liquid crystal display, in particular to a pixel circuit and a thin film transistor backplane for compensating threshold voltage drift. Background technique

[0002] Active Matrix Organic Light Emitting Diode (AMOLED) displays have been widely used due to their advantages of wide viewing angle, good color contrast, fast response and low cost. However, due to the unevenness and stability of the thin film transistor (Thin Film Transistor, TFT) backplane during the process, the threshold voltage will drift.

[0003] The traditional 2T1C pixel circuit such as figure 1 As shown, it includes: gate signal source VGATE, image frame data signal source VDATA, VDD signal source, switching transistor T1, driving transistor T2, storage capacitor C1 and organic light emitting diode (Organic Light Emitting Diode, OLED) D1, etc., where the switching transistor The gate of T1 is connected to the output terminal of the g...

Examples

Embodiment Construction

[0022] The specific implementation manners of a pixel circuit for compensating threshold voltage drift and a thin film transistor backplane provided by an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0023] A pixel circuit for compensating threshold voltage drift provided by the embodiment of the present invention has two implementation methods, the first one is as Figure 2a As shown, the structure of the pixel circuit specifically includes:

[0024] A signal loading module 21 and a driving module 22, wherein the signal loading module 21 is used to output the current frame data signal, and the driving module 22 includes a VDD signal source, a driving transistor T1, a storage capacitor C1, a p-type decay transistor T2 and an OLED D1, wherein, p The drain of the p-type attenuation transistor T2 is connected to the source of the drive transistor T1, the gate of the p-type attenuation transistor T2 is connected to the ...