LED Display Row Driving Compensation for Parasitic Capacitance
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Solution Overview
Problem
The existence of parasitic capacitance in LED display devices leads to color shift due to unequal current distribution among LEDs, particularly at low grayscales, resulting from unchanged current discharge through parasitic capacitance during display.
Innovation Solution
A driving method that compensates for display grayscale by using a display grayscale compensation table to adjust driving parameters, taking into account parasitic capacitance effects, thereby controlling LED display to mitigate color shift.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If parasitic capacitance is present in the LED display device, then the display can be driven with simple PMOSFET row switching, but color shift occurs due to unequal current distribution among LEDs
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the drive current based on the display grayscale level. Different drive currents are selected according to the grayscale value (e.g., first drive current for first grayscale range, second drive current for second grayscale range), which compensates for the varying impact of parasitic capacitance at different operating conditions, thereby maintaining uniform current distribution and preventing color shift.
2Adaptability or versatility
If low-level data signals with different widths are used to control LED brightness, then display grayscale can be adjusted, but color shift occurs due to unchanged current discharge through parasitic capacitance
Solution Approach 1:
The patent changes the drive current parameter based on the display grayscale level to compensate for parasitic capacitance effects. By selecting different drive currents corresponding to different grayscale ranges, the system maintains color consistency across various brightness levels while preserving the ability to adjust display grayscale.
3Duration of action of stationary object
If parasitic capacitance discharge current is not compensated, then the display can operate continuously, but color shift increases over time during display
Solution Approach 1:
The patent implements feedback compensation by detecting the display grayscale level and adjusting the drive current accordingly. This feedback mechanism compensates for the cumulative effect of parasitic capacitance discharge over time, maintaining color consistency throughout continuous display operation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method effectively reduces color shift by accounting for parasitic capacitance influences, ensuring uniform current distribution and improved LED display quality.
Implementation Method 1
due to the existence of parasitic capacitance, the current discharged by the parasitic capacitance remains unchanged during display, resulting in different proportions of the currents flowing through the LEDs to those entering the data driving chip, resulting in color shift
Data Source
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AI summary
The present application discloses a driving method of a display device and a display device. The display device includes multiple scan lines, multiple data lines, and multiple LED lights driven by the multiple scan lines and multiple data lines. The multiple LED lights are arranged in multiple rows and columns. An anode of each LED is connected to the respective scan line. A cathode of each LED is connected to the respective data line. The driving method includes: obtaining a compensated display grayscale corresponding to an LED in an instant row based on a display grayscale of an LED in the previous row, a display grayscale of the LED in the instant row, and a display grayscale compensation table; obtaining corresponding driving parameters according to the compensated display grayscale corresponding to the LED in the instant row; and controlling the LED in the instant row to display according to the driving parameters.