Touch Panel Wireless Interference Timing Coordination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Projective capacitive touch panels in electronic devices are highly susceptible to wireless signal interference from built-in wireless communication modules, particularly during near field communication or radio-frequency operations, which disrupts touch sensing functions.
Innovation Solution
A synchronous signal interface is established between the wireless communication module and the touch sensing module to coordinate the transmission of wireless signals and touch sensing operations, allowing the touch sensing module to stop sensing when wireless signals are transmitted or received, thereby reducing interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a wireless communication module is built into an electronic device with a projective capacitive touch panel, then the device gains wireless communication capability (NFC, RF), but the touch sensing function becomes susceptible to interference from wireless signals
Solution Approach 1:
The system performs preliminary action by stopping the touch sensing operation before wireless signal transmission begins. The controller receives a stop signal from the wireless communication module and halts the sensing operation in advance, preventing interference from occurring. This is implemented through timing control where the sensing operation is stopped during RF pulse generation and resumed after transmission completes.
2Speed
If the touch sensing module continuously scans for touch input, then touch response is immediate, but wireless signal transmission is interfered with causing data acquisition disruption
Solution Approach 1:
The system implements periodic action by alternating between touch sensing operations and wireless communication operations. Instead of continuous scanning, the touch sensing module operates periodically with intervals coordinated with wireless transmission cycles. The controller manages this by receiving timing signals and adjusting the scanning frequency to occur during safe time windows when no wireless transmission is active.
3Productivity
If the wireless communication module transmits RF signals during touch sensing operation, then wireless communication function is maintained, but touch data acquisition is disrupted
Solution Approach 1:
The system uses feedback mechanisms where the wireless communication module sends timing signals to the controller indicating when transmission is occurring. The controller uses this feedback to dynamically adjust the touch sensing operation, stopping scanning during RF transmission periods and resuming afterward. This ensures that touch data is not lost during communication intervals while maintaining wireless productivity.
Data Source
Figure 1
Figure 2A~2B
Figure 3A~3B
AI summary
A touch-controlled electronic device with a wireless communication function and a method for reducing wireless signal interference to a touch sensing function are disclosed. The electronic device includes a wireless communication module, a touch sensing module and a synchronous signal interface. By the synchronous signal interface, a synchronous signal is transmitted between the wireless communication module and the touch sensing module and, accordingly, the transmission of the wireless signal is staggered from the timing that receiver electrodes of the touch sensing module receive sensed signals. Thus, wireless signal interference to the touch sensing function of the touch sensing module is suppressed.