Source Driver Charge Sharing for Low Power Consumption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices, such as LCDs and OLEDs, require low power consumption for their driving devices due to their reduced size and weight, but existing solutions have not effectively addressed the need for minimizing power consumption in source drivers during both normal and blank periods.
Innovation Solution
A source driver design that includes output buffers controlled by power down signals and a charge sharing unit, allowing for reduced power consumption by enabling charge sharing between output buffers during blank periods, thereby minimizing current usage and voltage distribution across multiple channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If power down mode is enabled for output buffers during blank periods, then power consumption is reduced, but output voltage must be maintained for subsequent display periods
Solution Approach 1:
The patent applies the discarding and recovering principle by temporarily storing charge in the first output buffer during blank period power down mode, then recovering and redistributing this charge to multiple output terminals when the power down mode is disabled. This allows the buffer to be powered down during blank periods while ensuring voltage is available when needed for display periods.
Solution Approach 2:
The patent uses charge sharing switches as intermediary components that enable charge transfer between the first output buffer and multiple output terminals. These switches act as mediators that allow the buffer to share its stored charge with multiple terminals, solving the problem of maintaining output voltage after power down mode is disabled.
2Use of energy by moving object
If charge sharing is enabled between output buffers, then power consumption during blank periods is reduced, but device complexity increases due to additional switches and control signals
Solution Approach 1:
The patent applies segmentation by dividing the charge sharing function into discrete controllable switches (first charge sharing switch, second charge sharing switch) that can be independently controlled. This segmentation allows selective activation of charge sharing paths, managing complexity through modular control rather than a monolithic charge sharing unit.
Solution Approach 2:
The patent implements periodic action by controlling charge sharing switches based on periodic blank periods and display periods. The first and second power down signals are activated during blank periods and deactivated during display periods, creating a rhythmic charge sharing pattern that reduces average power consumption while maintaining display functionality.
3Use of energy by moving object
If multiple power down signals are used to control different output buffers, then selective power saving is achieved, but control signal complexity increases
Solution Approach 1:
The patent applies local quality by enabling different power down modes for different output buffers based on their specific requirements. The first power down signal controls the first output buffer while the second power down signal controls the second output buffer, allowing selective power saving in specific local regions (buffers) rather than uniform power down across all buffers.
Solution Approach 2:
The patent implements dynamics by making the power down control adaptive and flexible. The first and second power down signals can be independently activated or deactivated based on operational requirements, allowing the system to dynamically adjust which buffers are in power down mode versus active mode, optimizing power consumption while maintaining necessary output capabilities.
Data Source
AI summary
Disclosed are a source driver and a display device including the same. The source driver may include: an output buffer unit including a pair of output buffers controlled by a first power down signal and another pair of output buffers controlled by a second power down signal; and a charge sharing unit configured to control output buffers to share charge when the first or second power down signal is enabled, the output buffers being driven in the same driving range among the pair of output buffers and the other pair of output buffers.