Signal Regulator Module for LCD Backlight Current Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LCD backlight module driving circuits face challenges in maintaining uniformity of light intensity across multiple lamps, leading to reduced display quality and increased manufacturing costs due to the need for multiple transformers, and existing active balance circuits are inefficient in current regulation and lifespan of lamps.
Innovation Solution
A signal regulator module comprising floating current regulators, signal sensors, and a feedback controller that adjusts driving signals in real-time to ensure uniform current distribution across lamps, using a photo couple means to generate feedback signals and control the current regulators, allowing for simultaneous current regulation and image processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If multiple transformers are used to drive each lamp separately, then current uniformity and display quality are improved, but manufacturing cost and device complexity increase significantly
Solution Approach 1:
The patent divides the backlight system into multiple independently controllable lamp units, each driven by a separate switching element (MOSFET or IGBT). This segmentation allows individual current regulation for each lamp while using a single transformer, resolving the contradiction between current uniformity and device complexity.
Solution Approach 2:
The patent implements feedback control by sensing the current through each lamp and using this information to regulate the driving signal. The feedback mechanism ensures uniform current distribution across all lamps without requiring multiple transformers, thus improving manufacturing precision while maintaining reasonable device complexity.
2Device complexity
If a single transformer drives multiple lamps simultaneously, then manufacturing cost and device complexity are reduced, but current uniformity and display quality deteriorate
Solution Approach 1:
The patent employs dynamic control by independently adjusting the switching duty cycles of each lamp's switching element. This dynamic regulation allows the system to compensate for variations in lamp characteristics and maintain uniform current distribution while using a single transformer, thus reducing device complexity without sacrificing manufacturing precision.
Solution Approach 2:
The patent changes the electrical parameters (current, duty cycle) of each lamp independently through separate switching elements controlled by the microcontroller. By dynamically adjusting these parameters based on feedback, the system achieves uniform current distribution across multiple lamps driven by a single transformer.
3Manufacturing precision
If active balance circuits with transistors and comparators are used for current regulation, then current uniformity is improved, but lamp lifespan decreases due to waveform deformation
Solution Approach 1:
The patent replaces expensive and lamp-shortening active balance circuits with a microcontroller-based control system that uses simple switching elements and sensing resistors. This approach maintains current uniformity while avoiding the waveform deformation that shortens lamp lifespan, effectively substituting a more durable control architecture.
Solution Approach 2:
The patent substitutes the analog active balance circuit (with transistors, diodes, and comparators) with a digital control system using a microcontroller. This substitution eliminates the waveform deformation caused by active components while maintaining precise current regulation, thereby extending lamp lifespan.
4Manufacturing precision
If feedback control is implemented for current regulation, then current uniformity and display quality are improved, but response time and equilibrium achievement become slower
Solution Approach 1:
The patent implements periodic sampling of lamp currents through the microcontroller's ADC at optimized intervals. This periodic measurement approach, combined with duty cycle adjustment, achieves rapid equilibrium while maintaining current uniformity, resolving the contradiction between precision and response time.
Solution Approach 2:
The patent performs preliminary current balancing during the initialization phase before image processing begins. By pre-establishing uniform current distribution across all lamps, the system minimizes the time required to achieve equilibrium during subsequent operation while maintaining precision.
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 solution achieves real-time current regulation and uniformity across lamps, extending their lifespan and improving display quality by isolating high and low voltages, enabling efficient operation in large-size panels with dual-side driving structures.
Implementation Method 1
adjusts the first driving signal based on a first feedback signal in a photo couple means
Data Source
AI summary
A signal regulator module includes a floating current regulator, a signal sensor, and a feedback controller. The floating current regulator is electrically coupled to a driving circuit and the light sources of a display panel for regulating the driving signals based on a feedback signal in a photo couple means. The signal sensor is electrically coupled to the floating current regulator for generating a corresponding voltage signal based on the driving signal through a photo couple means. The feedback controller is electrically coupled to the signal sensor and the floating current regulator for generating the feedback signal based on the voltage signal and outputting the feedback signal to the floating current regulator.