Another month brigs us another blog post, this time, from one of our DRs.
From April 5th to August 8th, 2024, Subramaniam Saravana Sankar (DR04) went on his first secondment at NXP Semiconductors in the Czech Republic. This collaboration focused on exploring solutions for capacitive touch sensing technologies, particularly addressing challenges related to electromagnetic interference (EMI) and electromagnetic susceptibility (EMS). These are critical aspects for improving the performance of projected capacitive touch systems used in smartphones, tablets, automotive interfaces, and other interactive displays.
The Challenge of EMI in Touch Sensing Systems
Capacitive touch systems are highly susceptible to electromagnetic disturbances, which can significantly impact their reliability and user experience. This issue is especially pronounced in applications that demand high precision and responsiveness, such as automotive displays. The research primarily centered on a widely used, yet limited method: the relaxation oscillator. Though cost-effective and simple, this method struggles to maintain a stable signal-to-noise ratio (SNR) in the presence of EMI.
Initial findings revealed that current charge transfer-based sensing approaches provide only minimal improvements in SNR, which is insufficient for high-reliability applications in a vehicle. This prompted a deeper exploration into alternative solutions for EMI mitigation.
Innovative Solutions for EMI Mitigation
DR4 investigated various strategies to enhance the resilience of capacitive touch systems against EMI. These included:
- Advanced Filtering Techniques: To effectively filter out unwanted electromagnetic signals.
- Improved Circuit Design: Redesigning circuits to optimise their resistance to EMI.
- Novel Materials: Evaluating alternative materials that can improve the sensors’ overall robustness.
- Signal Processing Algorithms: Introducing advanced algorithms to boost the system’s capacity to deal with interference.
Moreover, the potential of integrating novel shielding methods was evaluated to make the touch sensors more resilient in high-EMI environments.
Below are some photos of our DR Subramaniam Saravana Sankar.
This collaborative research would not have been possible without the invaluable support from Ing. Michael Galda from NXP Semiconductors, who provided essential systems engineering insights throughout the secondment. Special thanks are also due to Dr. Ing. Stanislav Kovář, for his supervision and guidance throughout the research period.
This is all for now. For more updates on the DN PARASOL, stay tuned!
Until next time!