Data Driving Circuit MSB Detection Prevents Data Line Overcharging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display driving circuits often overcharge data lines, leading to brighter display regions and affecting the overall performance of display devices.
Innovation Solution
A data driving circuit with a second latch module that detects the most significant bit (MSB) of sampled signals and controls pre-charge or pre-discharge operations to ensure data lines reach a specified voltage, preventing overcharging by disabling pre-operations when the grayscale value is within a specified range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the DAC circuit pre-charges the data line when the MSB changes, then the data line voltage reaches the target voltage faster, but the data line may be overcharged causing the display region to be brighter
Solution Approach 1:
The patent implements a feedback mechanism by detecting the MSB value and using it to control the pre-charging operation. The detection unit monitors the MSB of the sampled signal, and based on this feedback, the control unit decides whether to enable or disable the pre-charging function, thereby preventing overcharging while maintaining fast voltage response
Solution Approach 2:
The patent changes the operating parameters of the pre-charging circuit based on the MSB value. When the MSB indicates a grayscale value within a specified range, the pre-charging voltage or duration is adjusted or disabled, preventing overcharging. This dynamic parameter adjustment resolves the contradiction between fast voltage response and preventing excessive brightness
2Loss of time
If the pre-charging operation is always enabled when MSB changes, then display response time is reduced, but power consumption increases due to unnecessary pre-charging
Solution Approach 1:
Instead of always enabling pre-charging when MSB changes, the patent applies partial action by enabling pre-charging only when the MSB value falls outside a specified grayscale range. This selective application of pre-charging reduces unnecessary power consumption while maintaining fast response times when actually needed
Solution Approach 2:
The system uses the MSB information from the sampled signal itself to automatically control the pre-charging operation. The detection unit and control unit work together to self-regulate the pre-charging based on the actual data being displayed, eliminating the need for external control and reducing wasted energy
Data Source
AI summary
A data driving circuit proofed against excessive pixel brightness because of overvoltage on the data line comprises a shift register circuit, a first latch circuit, a second latch circuit, a level shift circuit, a DAC circuit, and an output circuit. The second latch circuit detects a change in the MSB of the data signal of a sampled signal, and outputs a signal for applying a pre-operation of the current data line. When the MSB of the sampled signal is changed, the second latch circuit outputs a pre-operation enabling signal, and whether the grayscale value of the current data line is within a specified region. If within the specified region, the second latch circuit outputs an invalid signal, and the pre-operation is disabled.