OLED Pixel Driving Circuit With Leakage Compensation for Flicker Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Low-frequency driving pixel circuits in OLED displays suffer from flickering issues due to leakage currents, which degrade display quality.
Innovation Solution
A pixel driving circuit with a data writing sub-circuit and a light-emitting control sub-circuit that applies data signals to a leakage current compensation point, compensating the voltage of the driving sub-circuit's control electrode during the light-emitting phase to stabilize the gate voltage of the driving transistor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional pixel driving circuit is used in low-frequency OLED display, then the display can operate with simple circuit structure, but flickering occurs due to leakage current and display quality deteriorates
Solution Approach 1:
The pixel driving circuit is divided into multiple functional sub-circuits: a data writing sub-circuit for writing data signals, a leakage current compensation sub-circuit for compensating leakage current, and a light-emitting control sub-circuit for controlling light emission. This segmentation allows each sub-circuit to perform its specific function efficiently, resolving the contradiction between improved reliability and reduced complexity.
Solution Approach 2:
A leakage current compensation point is introduced as an intermediary element between the data writing sub-circuit and the light-emitting control sub-circuit. This compensation point receives the data signal and applies it to compensate for leakage current effects, thereby improving display quality without significantly increasing overall circuit complexity.
2Stability of the object's composition
If data signal is applied to leakage current compensation point, then gate voltage stability is improved, but additional circuit components are required
Solution Approach 1:
The data writing sub-circuit is designed to perform multiple functions: writing the data signal into the driving sub-circuit and simultaneously applying the data signal to the leakage current compensation point. This multi-functionality reduces the need for separate dedicated components, thereby improving gate voltage stability while minimizing the increase in circuit complexity.
Solution Approach 2:
The leakage current compensation function is merged with the data writing function by using the same data signal path. The data signal serves dual purposes: driving the display and compensating for leakage current, thus reducing the number of additional components needed while achieving voltage stability.
3Reliability
If leakage current compensation is implemented, then flickering is reduced, but the circuit requires additional control signals
Solution Approach 1:
The leakage current compensation is performed in advance during the data writing phase before the light-emitting phase begins. By pre-compensating for leakage current effects using the data signal, the circuit eliminates the need for additional real-time compensation control signals during light emission, thereby reducing flicker while minimizing control signal complexity.
Data Source
AI summary
Provided are a pixel driving circuit (110) and a driving method, a display panel (610) and a display device (900). The pixel driving circuit (110) includes: a driving sub-circuit (111) connected to a light-emitting element (120); a data writing sub-circuit (112) configured to write a data signal from the data signal terminal (Vdata) into the driving sub-circuit (111) and apply the data signal-to a leakage current compensation point (M), under control of the scanning signal terminal (Vscan); and a light-emitting control sub-circuit (113) configured to control the driving sub-circuit (111) to output a driving current related to the data signal to the light-emitting element (120) under control of the light-emitting control signal terminal (EM). In a process of emitting light by the light-emitting element (120), a voltage of a control electrode of the driving sub-circuit (113) is compensated by a voltage of the leakage current compensation point (M).