Parallel Capacitive Sensor Acquisition via Segmented Channel Groups
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional capacitive touch systems face challenges with noise interference, particularly from displays and moisture, which can cause unwanted mutual capacitance effects, leading to reduced signal-to-noise ratio (SNR) and slower parsing speeds.
Innovation Solution
The implementation of a parallel acquisition method that simultaneously measures channel capacitance from multiple active sense channels using orthogonal polarity codes, allowing for improved noise tolerance and faster parsing speeds without compromising SNR, by decoupling the tradeoff between parsing speed and SNR.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If single-channel acquisition is used, then noise immunity is maintained, but parsing speed is slow and processing time increases
Solution Approach 1:
The patent segments the sense channels into multiple groups that can be measured in parallel. Instead of measuring all sense channels sequentially through a single acquisition channel, the system divides them into multiple groups, each measured by dedicated acquisition channels simultaneously, thereby increasing parsing speed while maintaining noise immunity through grouped measurement.
Solution Approach 2:
The patent combines multiple sense channel measurements into parallel acquisition operations. By merging the measurement processes of multiple sense channel groups into simultaneous operations, the system achieves faster overall parsing speed without sacrificing the noise immunity that would result from individual channel measurement.
2Productivity
If multiple sense channels are measured in parallel, then parsing speed increases, but noise interference and mutual capacitance effects worsen
Solution Approach 1:
The patent segments sense channels into multiple groups where each group is measured in parallel by dedicated acquisition channels. This segmentation allows high processing throughput while limiting noise interference within each group, as the number of simultaneously measured channels in each group is controlled and manageable.
Solution Approach 2:
The patent introduces drive lines as intermediaries between the sense lines and acquisition channels. These drive lines are configured with specific drive signals that facilitate the measurement process while minimizing mutual capacitance effects and noise interference, enabling parallel measurement of multiple sense channel groups without excessive noise coupling.
3Reliability
If sequential measurement of sense channels is used, then noise interference is minimized, but parsing speed and processing efficiency decrease
Solution Approach 1:
The patent segments sense channels into multiple groups that can be measured in parallel while maintaining measurement accuracy within each group. This segmentation approach preserves the noise immunity benefits of controlled measurement while achieving high parsing speed through simultaneous processing of multiple groups.
Solution Approach 2:
The patent creates a measurement system with universal applicability where multiple acquisition channels can simultaneously measure multiple sense channel groups using the same measurement principles. This multi-functional approach maintains measurement accuracy and reliability across all channels while achieving high parsing speed through parallel operations.
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 enhances the signal-to-noise ratio by √N times that of single-channel acquisition systems, enabling faster parsing speeds and improved noise immunity, allowing for larger touch panels to be processed within the same time constraints while reducing power consumption.
Implementation Method 1
capacitive sensor circuitry... determine at least one channel capacitance of at least one active sense line
Implementation Method 2
drive lines and sense lines... groups of drive signals... polarity changes
Data Source
AI summary
Embodiments of the disclosure relate, generally, to techniques for parallel acquisition and measurements and related circuits, systems and devices that implement those techniques. A technique for parallel acquisition and measurement generally includes simultaneously acquiring sensed signals from multiple sensor channels and determining channel capacitance measurements responsive to the sensed signals.