Display Driver IC Gamma Adjustment for Pixel Voltage Variations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The luminance of display device pixels is affected by changes in pixel driving voltage due to internal and external loads, leading to non-linear luminance variations despite constant analog data voltage.
Innovation Solution
A display device with a driver IC that includes a weight selector and gamma reference voltage generating circuit to adjust the gamma voltage based on pixel driving voltage changes, using a voltage divider circuit and multiplexer to boost or reduce the pixel driving voltage by a specified multiple, generating gamma reference voltages to stabilize luminance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pixel driving voltage is supplied to drive the display panel, then the pixels can operate and display images, but the luminance of pixels changes due to voltage variations caused by internal and external loads
Solution Approach 1:
The patent implements a feedback mechanism where the gamma reference voltage generating circuit continuously monitors the pixel driving voltage and adjusts the gamma reference voltage accordingly. When the pixel driving voltage changes due to load variations, the circuit detects this change and generates a compensated gamma reference voltage to maintain stable luminance output
Solution Approach 2:
The patent changes the gamma reference voltage parameter in response to pixel driving voltage variations. By adjusting the gamma reference voltage based on the detected voltage changes, the system compensates for luminance variations and maintains consistent display quality under different load conditions
2Reliability
If gamma voltage is adjusted to compensate for pixel driving voltage changes, then luminance stability is improved, but the device complexity increases due to additional circuits
Solution Approach 1:
The patent merges the gamma reference voltage generating circuit with the existing driver IC structure. By integrating the voltage adjustment functionality into the existing circuit framework rather than adding completely separate compensation circuits, the patent reduces overall device complexity while still achieving luminance stability
Solution Approach 2:
The gamma reference voltage generating circuit serves multiple functions: it generates the gamma reference voltage, detects pixel driving voltage variations, and performs compensation adjustments. This multi-functionality reduces the need for separate dedicated circuits for each function, thereby reducing overall device complexity
Data Source
AI summary
A display device includes: a display panel including a plurality of pixels, a driver integrated circuit (IC) configured to convert digital data corresponding to an input image to an analog data voltage using a gamma voltage, and to supply the analog data voltage to the plurality of pixels, and a power supply configured to supply a pixel driving voltage to the display panel and the driver IC, and the driver IC includes: a weight selector configured to select a weight for adjusting the gamma voltage based on an amount of change in the pixel driving voltage supplied from the power supply, and a gamma reference voltage generating circuit configured to generate a gamma reference voltage based on the selected weight.