Touch Display Driving Device Multiplexing Common Electrode Blocks

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional touch display devices with TDDI drivers face issues of slow recovery speed and discontinuous display quality due to high resistance paths from the common voltage generation circuit to common electrodes, leading to abnormal display during touch detection.

Innovation Solution

A multiplexing circuit is used to selectively couple common electrode blocks to either a first voltage during display periods for active regions and a second voltage during non-display periods, reducing the loading and power consumption on the common voltage generation circuit, thereby increasing recovery speed and maintaining display quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If all common electrode blocks are coupled to common voltage VCOM during display period, then display coverage is improved, but recovery speed deteriorates due to high resistance paths

Engineering Contradiction:

Improvedisplay coverage areaVSAvoidrecovery speed

Core Design Contradiction:

Area of stationary objectVSSpeed

Solution Approach 1:

The common electrode blocks are segmented into multiple groups, with each group coupled to VCOM independently during different time periods. This allows selective activation of only the electrode blocks needed for current display refresh, reducing the total capacitance load and enabling faster voltage recovery while maintaining adequate display coverage through sequential refresh.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The common electrode blocks are activated in periodic cycles rather than continuously. Each block is coupled to VCOM during its designated display period and then decoupled during touch detection period or when not needed for display, creating a periodic activation pattern that reduces average loading on the voltage generation circuit and improves recovery speed.

Inventive Principle:

Principle #19Periodic action

2Stability of the object's composition

If all common electrode blocks are coupled to common voltage VCOM during display period, then display continuity is improved, but power consumption increases

Engineering Contradiction:

Improvedisplay continuityVSAvoidpower consumption

Core Design Contradiction:

Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The common electrode blocks are divided into multiple segments that are activated only when needed for display refresh. By segmenting the electrode blocks and selectively coupling only the necessary segments to VCOM during each display period, the patent reduces the total power consumption while maintaining display continuity through coordinated sequential refresh of different segments.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of coupling all common electrode blocks to VCOM simultaneously, the patent applies partial action by coupling only the specific electrode blocks needed for the current display refresh operation. This partial activation approach maintains adequate display continuity for the active region while significantly reducing overall power consumption compared to full activation.

Inventive Principle:

Principle #16Partial or excessive action

3Adaptability or versatility

If common electrodes are coupled to touch detecting circuit during touch detection period, then touch detection capability is improved, but display quality deteriorates due to slow recovery

Engineering Contradiction:

Improvetouch detection capabilityVSAvoiddisplay quality

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The common electrode blocks are periodically switched between display mode (coupled to VCOM) and touch detection mode (coupled to touch detecting circuit). This periodic switching allows the system to alternate between maintaining display quality and enabling touch detection, with each electrode block spending appropriate time in each mode to balance both functions without compromising display quality during refresh periods.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The coupling configuration of common electrode blocks is made dynamic rather than static. Each electrode block can be dynamically reconfigured during operation to be coupled to either the voltage generation circuit or the touch detecting circuit based on current operational needs. This dynamic reconfiguration enables the system to adapt between display and touch detection modes, improving touch detection capability while maintaining display quality through timely voltage recovery.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS11182018B2Touch display driving device and driving method in the same

Publication Date: 2021.11.23 NOVATEK MICROELECTRONICS CORP

AI summary

The present invention discloses a touch display driving device and a driving method in the same. The touch display driving device is used for driving a touch display panel, the touch display panel comprising a plurality of common electrode blocks and a plurality of display regions. The touch display driving device comprising a multiplexing circuit which is configured to: during a display period, couple one or more common electrode blocks corresponding to one of the display regions which is to be displayed during the display period to a first voltage; and during the display period, couple one or more of the common electrode blocks corresponding to the display regions which are not to be displayed during the display period to a second voltage.