Display Device Charge Recycling Circuit for Power Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing display devices, particularly organic electroluminescent devices, face high power consumption due to the discharge of electric charges from data lines, leading to rapid battery depletion.

Innovation Solution

A circuit driving device that includes a feedback circuit with a charge storing circuit and a comparing circuit, which feeds electric charges discharged from the data lines back to the battery, optimizing power usage by storing and redistributing charges efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If data lines are discharged during discharge time to prepare for next frame, then display performance is maintained, but power consumption increases and battery life decreases

Engineering Contradiction:
Improvedisplay performanceVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements a feedback mechanism where the discharge circuit is controlled by a control signal that is generated based on the detection of the current frame's display completion. The control signal feeds back to the discharge circuit to trigger the next frame's data line discharge only when necessary, avoiding unnecessary discharge operations and reducing power consumption while maintaining display performance.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent changes the discharge voltage parameter by using a controllable voltage source that can adjust the discharge voltage level. By optimizing the discharge voltage to the minimum required level for proper display operation, the patent reduces the energy consumed during discharge operations while maintaining adequate display performance for the next frame.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If discharge voltage is increased to ensure proper pixel operation, then pixel performance is improved, but power consumption increases

Engineering Contradiction:
Improvepixel operationVSAvoiddischarge power
Core Design Contradiction:
ReliabilityVSPower

Solution Approach 1:

The patent employs parameter changes by dynamically adjusting the discharge voltage to the minimum effective level required for proper pixel operation. The controllable voltage source in the discharge circuit allows precise control of discharge voltage, optimizing it to balance pixel performance with power consumption reduction.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies partial action by discharging data lines only to the extent necessary for proper pixel operation in the next frame, rather than using excessive discharge voltage. This partial discharge approach is sufficient to clear residual charges and prepare pixels for new data, reducing power consumption while maintaining pixel operation reliability.

Inventive Principle:
Principle #16Partial or excessive action

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

This approach reduces power consumption and extends battery life by recycling electric charges, thereby improving the overall efficiency of the display device.

Implementation Method 1

a discharging circuit (308) which discharges the data lines (D1 to D4) to a voltage of a zener diode (ZD)

Methodology Applied
Scientific EffectZener breakdown: Avalanche Breakdown

Data Source

PatentEP1895494B1Display device and method of driving the same
Publication Date: 2019.07.03 LG DISPLAY CO LTD
  • EP1895494B1 patent drawingFigure 1
  • EP1895494B1 patent drawingFigure 2A
  • EP1895494B1 patent drawingFigure 2B

AI summary

The present invention relates to a display device for providing charges discharged from data lines to a battery. The display device includes data lines, scan lines, pixels, a charge storing circuit and a discharging circuit. The pixels are formed in cross areas of the data lines and the scan lines, and driven on the basis of a driving voltage. The charge storing circuit is coupled to at least one data line during a first sub-discharge time of a discharge time, and stores electric charges discharged from the data line during the first sub-discharge time. The discharging circuit is coupled to the data line during a second sub-discharge time of the discharge time, and discharges the data line up to a certain discharge voltage during the second sub-discharge time.