OLED Pixel Circuit Voltage Compensation for IR Drop
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The IR drop of power supply voltage signals in pixel circuits affects the luminous brightness of OLED light-emitting devices, impacting the display effect in AMOLED panels.
Innovation Solution
A pixel circuit comprising a charge control module, a drive module, a reset control module, and a light-emitting control module, where the charge control module switches on the data signal and reset control module under scan control, and the reset control module resets and compensates the reference voltage, allowing the light-emitting control module to drive the light-emitting device independently of the power supply voltage signal during the light-emitting phase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional pixel circuit is used, then the structure is simple, but the IR drop of power supply voltage signals affects luminous brightness
Solution Approach 1:
The pixel circuit is divided into multiple functional modules: charge control module, drive module, reset control module, light-emitting control module, and light emitting device. Each module performs a specific function, allowing independent optimization of voltage compensation while maintaining overall circuit functionality.
Solution Approach 2:
The reset control module performs preliminary voltage compensation by resetting the control end and output end of the drive module before the light-emitting phase. This preliminary action compensates for reference voltage variations, ensuring stable drive current and luminous brightness before actual light emission occurs.
2Illumination intensity
If voltage compensation is implemented, then luminous brightness stability is improved, but device complexity increases
Solution Approach 1:
The reset control module serves multiple functions: it resets the drive module voltage levels and compensates for reference voltage variations. This multi-functionality reduces the need for separate compensation circuits, thereby limiting the increase in device complexity while achieving voltage stability.
Solution Approach 2:
The circuit implements feedback through the reset control module that monitors and compensates for voltage variations at the drive module outputs. This feedback mechanism ensures stable luminous brightness by automatically adjusting for voltage drops without requiring complex external compensation circuits.
Data Source
AI summary
A pixel circuit, an organic electroluminescent display panel and a display device, in a reset and compensation phase, a charge control module of the pixel circuit makes a data signal end and the first input end of a reset control module switch on, and the reset control module resets the control end and a output end of a drive module and compensates reference voltage; in a data writing phase, the charge control module writes the data signal inputted by the data signal end to the first input end of the reset control module; in a light-emitting phase, a light-emitting control module makes the output end of the drive module and the input end of the light emitting device switch on and drives the light emitting device to emit light by integrating the data signal inputted into the drive module with the reference voltage signal compensated into the drive module, which realizes the effect that the drive current driving the light emitting device to emit light is irrelevant to the power supply voltage signal, eliminates the influence on luminous brightness of the light emitting device caused by IR drop of the power supply voltage signal inputted into the pixel circuits, and further guaranteeing the display effect of the display panel.