Touch Panel Driving Circuit Parasitic Capacitor Voltage Stabilization

Solution Overview

Problem

Current touch panel driving circuits require external voltage stabilizing capacitors, increasing circuit area and component costs due to the need for high-output power boost circuits.

Innovation Solution

The use of parasitic capacitors inherent to the touch panel as voltage stabilizing capacitors, eliminating the need for external capacitors by generating scan signals through multiple signal generating circuits that correspond to scan electrodes, reducing the required output power and eliminating the need for additional capacitors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a high-output power boost circuit is used to generate scan signals for multiple scan electrodes, then the scan signal generation capability is improved, but the circuit area increases due to the requirement of external large-capacitance voltage stabilizing capacitors

Engineering Contradiction:

Improveoutput power of boost circuitVSAvoidcircuit area

Core Design Contradiction:

PowerVSArea of stationary object

Solution Approach 1:

The patent merges the voltage stabilizing capacitor function into the touch panel structure itself by utilizing the parasitic capacitance formed between the scan electrodes and the common electrode. This eliminates the need for separate external voltage stabilizing capacitors, thereby reducing circuit area while maintaining the required output power capability for driving multiple scan electrodes

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The touch panel structure provides its own voltage stabilizing function through the inherent parasitic capacitance between electrodes. The parasitic capacitance that normally represents a parasitic effect is instead utilized as a functional component to stabilize the scan signal voltage, making the system self-sufficient and eliminating external component requirements

Inventive Principle:

Principle #25Self-service

2Reliability

If external large-capacitance voltage stabilizing capacitors are added to stabilize output voltage, then voltage stability is improved, but the cost of external components increases

Engineering Contradiction:

Improvevoltage stabilityVSAvoidcost of external components

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The touch panel structure provides its own voltage stabilizing function through the inherent parasitic capacitance between electrodes. The parasitic capacitance that normally represents a parasitic effect is instead utilized as a functional component to stabilize the scan signal voltage, making the system self-sufficient and eliminating external component requirements

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent converts the harmful parasitic capacitance effect into a beneficial functional component. The parasitic capacitance between scan electrodes and common electrode, which traditionally represents signal loss and interference, is instead harnessed to provide voltage stabilization, eliminating the need for external capacitors and reducing component costs

Inventive Principle:

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

3Device complexity

If a single boost circuit serves multiple scan electrodes, then device complexity is reduced, but the required output power increases requiring larger capacitors

Engineering Contradiction:

Improvenumber of boost circuitsVSAvoidoutput power of boost circuit

Core Design Contradiction:

Device complexityVSPower

Solution Approach 1:

The patent merges the voltage stabilizing capacitor function into the touch panel structure itself by utilizing the parasitic capacitance formed between the scan electrodes and the common electrode. This eliminates the need for separate external voltage stabilizing capacitors, thereby reducing circuit area while maintaining the required output power capability for driving multiple scan electrodes

Inventive Principle:

Principle #5Merging (Combining)

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 circuit area and external component costs while maintaining effective touch panel functionality, as the parasitic capacitors within the touch panel stabilize the scan signals, eliminating the need for external voltage stabilizing capacitors.

Implementation Method 1

the parasitic capacitor of the touch panel is used as the voltage stabilizing capacitor

Methodology Applied

Scientific EffectParasitic capacitance: Parasitic Capacitance

Data Source

PatentUS11099684B2Method and structure for a driving circuit of touch panel touch device and touch module

Publication Date: 2021.08.24 XMYTH IP GRP LTD

AI summary

The present invention relates to a driving circuit, the touch device thereof, the touch module thereof, and the method for manufacturing the same. The present invention comprises a control circuit, a scan circuit, a touch panel, and a detection circuit. The control circuit generates an input signal. The scan circuit comprises a plurality of signal generating circuits, which receive the input signal, generate a plurality of scan signals according to the input signal, and output the plurality of scan signals to the plurality of scan electrodes of the touch panel. The detection circuit detects the touch panel according to the plurality of scan signals and outputs a detection signal to the control circuit to let the control circuit know at least a touch point of the touch panel being touched.