Proprietary sensor design

After the choice of driver IC, the design of the sensor is the most important part of achieving the required system performance and yet is often the most compromised part of the overall capacitive touchscreen system. The main reason for this is that the design guides provided by the sensor IC vendors are quite conservative documents which try to take account of a broad range of sensor manufacturing techniques and vendors.

TouchNetix approach is focussed on ensuring that the sensor design is fully optimised for the end users product while accounting for the compromises which need to be made for the sensors to be manufactured using commonly available materials and at reasonable yields. TouchNetix typically achieves 90%+ of the theoretical performance achievable for any given set of parameters.

The TouchNetix sensor design process has been optimised through simulation and automation. Taking the inputs from the materials properties, the stack of the sensor and the comfortable sensor manufacturing envelope, we are able to predict key performance parameters such as charge time, touch delta and SNR before sensors are built. The output of our simulation tools is then run through a fully automated design tool which generates a ready-to-manufacture digital file (including edge wiring) without resort to any drawing tools. This leads to right-first-time prototypes and the best possible performance.

The very best technology Animated GIF

Highly EMC & ESD tolerant

In industrial, home appliance and other mission critical applications, one of the more challenging aspects of meeting the specification requirements is for EMC tolerance and particularly for injected current noise tolerance. The specification requirements for noise tolerance are noted in EN61000-4-6.

Meeting Class A requirements at 10V RMS is challenging for a capacitive touch system and requires that all aspects of the system design and of tuning the system in end product to meet the requirement is quite critical. There are often specific frequency ranges of interest to certain users, for example in the case of applications where a high powered RF transmitter is in close proximity. Optimising the design and then tuning the end system for the best overall noise performance is an area where TouchNetix expertise provides you with an edge over your competitors.

Touch target area on touchscreen

The right driver IC

The best capacitive touchscreen designs must consider that while there are many capacitive touchscreen driver IC manufacturers in the world, the majority of these IC’s have been developed specifically to be low cost for consumer electronics applications. TouchNetix have evaluated a broad range of IC’s and typically select based on the most cost effective IC needed on a project which can meet the required performance. Driver IC’s also vary greatly in how ‘easy’ it is to tune the system to work in any given application. The most versatile IC’s have a broad range of parameters which can be tuned using appropriate software tools such as TouchNetix proprietary ‘TouchHub’ software whereas others can only be tuned by direct modification of the firmware load which means that support can be a challenge.

The driver IC has a strong influence over how the overall capacitive touch system will perform and, particularly in areas like noise tolerance in high EMC environments. The most advanced IC’s use noise avoidance features such as frequency hopping to improve the system SNR whereas the more basic IC’s rely on software filtering to achieve a similar result.

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Tuned to perform flawlessly in your system

TouchNetix use their deep knowledge of how the driver IC’s work to simulate the overall system performance, allowing us to predict touch behaviour in the end user applications. The performance of the system must be finally evaluated and tuned in a good representation of our customers end product; this is readily achieved using TouchNetix proprietary tuning tools which we provide to our customers. These tools can even be configured for remote use by TouchNetix to achieve the most optimum configuration and best capacitive touchscreen performance whatever the end environment may be.

TouchNetix philosophy is not just to design and deliver a capacitive touchscreen, rather to ensure that our customers end product has a capacitive touch solution which meets their requirements.

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