Touch Screen Signal Processing Circuit Noise Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Touch screen devices face instability and increased cost due to noise interference, which distorts output voltages and makes it difficult to distinguish touch inputs, requiring additional capacitors and increased circuit area.
Innovation Solution
A signal processing circuit for touch screens that shares capacitance between channels by controlling switches, allowing operation in normal or distortion modes to manage noise, without the need for additional capacitors, by connecting adjacent sensing channels in parallel when noise is detected.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If additional capacitors are added to increase capacitance when noise occurs, then touch input detection stability is improved, but circuit area and manufacturing cost increase
Solution Approach 1:
The patent merges capacitance resources from multiple sensing channels by connecting adjacent sensing channels in parallel through switch control. This allows the capacitance of neighboring channels to be combined and shared, providing increased capacitance for noise suppression without adding separate capacitor components, thereby maintaining compact circuit area while improving touch detection stability under noisy conditions
Solution Approach 2:
The patent enables sensing channel capacitors to serve multiple functions: they function as individual channel capacitors during normal operation and as shared capacitance resources when noise is detected. This multi-functionality allows existing capacitors to provide both channel-specific and noise-suppression functions, eliminating the need for additional dedicated capacitors and reducing overall circuit area
2Reliability
If additional capacitors are added to increase capacitance when noise occurs, then touch input detection stability is improved, but manufacturing cost increases
Solution Approach 1:
The patent merges capacitance resources from multiple sensing channels by connecting adjacent sensing channels in parallel through switch control. This allows the capacitance of neighboring channels to be combined and shared, providing increased capacitance for noise suppression without adding separate capacitor components, thereby maintaining compact circuit area while improving touch detection stability under noisy conditions
Solution Approach 2:
The patent enables sensing channel capacitors to serve multiple functions: they function as individual channel capacitors during normal operation and as shared capacitance resources when noise is detected. This multi-functionality allows existing capacitors to provide both channel-specific and noise-suppression functions, eliminating the need for additional dedicated capacitors and reducing overall circuit area
3Reliability
If capacitance is increased to reduce noise distortion, then output voltage distortion is reduced, but circuit complexity increases
Solution Approach 1:
The patent implements dynamic capacitance adjustment by using switch control to connect or disconnect adjacent sensing channels based on noise detection results. The capacitance configuration changes dynamically between normal mode (individual channel operation) and distortion mode (parallel connection for increased capacitance), allowing the circuit to adapt to varying noise conditions without permanent structural complexity
Solution Approach 2:
The patent introduces switch control units as intermediary elements that manage the connection between sensing channels. These switches act as mediators that can connect adjacent sensing channels in parallel when noise is detected, enabling flexible capacitance adjustment without requiring complex permanent circuit structures, thus reducing overall circuit complexity while maintaining output stability
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 stabilizes touch input detection by increasing capacitance when noise occurs, reducing distortion and maintaining circuit efficiency without increasing cost or power consumption.
Implementation Method 1
a capacitor and a plurality of sensing channel switches; when the distortion detection unit determines that distortion due to noise has occurred, the control unit operates the sensing channel switches to connect the capacitor to an adjacent sensing channel in parallel
Data Source
AI summary
A signal processing circuit of a touch screen panel is provided. A signal processing circuit can include a plurality of driving lines and sensing lines intersecting on the touch screen panel, a plurality of sensing channels connected to the sensing lines respectively and configured to detect whether a touch is performed by sensing mutual capacitance on intersecting nodes of the driving lines and the sensing lines, a distortion detection unit configured to detect whether distortion due to noise occurs on the basis of output voltages of the sensing channels, and a control unit configured to operate switches to alternate the circuit between a distortion mode and a normal mode, depending on whether noise is detected.