Corner-Cut Gate Driving Circuit for Parasitic Capacitance Control

Solution Overview

Problem

Existing display devices face image distortion due to parasitic capacitance effects during scanning, which affects the voltage of data signals and degrades image quality, especially in high-resolution displays.

Innovation Solution

A gate driving circuit comprising a corner cutting circuit and a scanning circuit that output smoothed corner cut voltage and scanning signals, respectively, to reduce the voltage change on scanning lines, thereby minimizing the impact of parasitic capacitance on data signals and extending the ON time of switch transistors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional scanning signals with sharp edges are used, then the scanning speed and response time are fast, but parasitic capacitance effects cause voltage changes on scanning lines that distort data signals and degrade image quality

Engineering Contradiction:

Improveimage qualityVSAvoidscanning speed

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The scanning signal waveform is dynamically adjusted by changing its shape from a conventional sharp-edge pulse to a corner-cut waveform. This dynamic modification of the signal characteristics allows the signal to maintain sufficient transition speed while reducing high-frequency components that interact with parasitic capacitance, thereby resolving the contradiction between scanning speed and image quality

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The corner-cut amount and corner-cut time of the scanning signal are optimized as key parameters. By adjusting these parameters, the signal waveform is modified to reduce voltage changes on scanning lines during the transition period, minimizing parasitic capacitance effects on data signals while maintaining acceptable scanning speed for high-resolution displays

Inventive Principle:

Principle #35Parameter changes

2Productivity

If the scanning signal has sharp transitions, then the signal switching is fast and efficient, but the voltage change on scanning lines at cut-off times causes harmful parasitic capacitance effects on data signals

Engineering Contradiction:

Improvesignal switching efficiencyVSAvoidparasitic capacitance effects

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The invention converts the harmful sharp-edge transitions that cause parasitic capacitance effects into beneficial corner-cut waveforms. By intentionally adding corner-cut portions to the scanning signal, the high-frequency components are reduced, which minimizes the harmful voltage changes on scanning lines while maintaining the signal's ability to switch states efficiently

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The scanning signal waveform is dynamically adjusted by changing its shape from a conventional sharp-edge pulse to a corner-cut waveform. This dynamic modification of the signal characteristics allows the signal to maintain sufficient transition speed while reducing high-frequency components that interact with parasitic capacitance, thereby resolving the contradiction between scanning speed and image quality

Inventive Principle:

Principle #15Dynamics

Solution Approach 3:

The corner-cut amount and corner-cut time of the scanning signal are optimized as key parameters. By adjusting these parameters, the signal waveform is modified to reduce voltage changes on scanning lines during the transition period, minimizing parasitic capacitance effects on data signals while maintaining acceptable scanning speed for high-resolution displays

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS10291224B2Gate driving circuit, driving method thereof, display panel and display device

Publication Date: 2019.05.14 BOE TECHNOLOGY GROUP CO LTD

AI summary

Embodiments of this disclosure provide a gate driving circuit, a driving method thereof, a display panel and a display device. The gate driving circuit comprises: a corner cutting circuit and a scanning circuit. The corner cutting circuit is configured to output a corner cut voltage signal, wherein the corner cut voltage signal comprises a pulse whose edge is smoothed. The scanning circuit is configured to output a corner cut scanning signal based on the corner cut voltage signal, wherein the corner cut scanning signal comprises a pulse whose edge is smoothed.