Which PSOC/MCU Device Works Best for Trackpad? (Mutual Capacitance/CSX)

[JoJo_4453281]

I have designed a touchpad product and would like to begin the next phase of development: Ordering components, putting them together, testing them, refining design, etc. THE FUN STUFF! I am very new to PSoC design and electrical engineering in general, but I understand how mutual capacitance/CSX works on a theoretically level with Rx/Tx electrodes, hatched ground plane, etc.

The requirements for this trackpad is that it can:

1. Sense multiple touch points

2. Send the data wirelessly to a computer.

3. Latency-free (not noticeable/under 5-10ms)

What I need to know to confidently move on is what family of PSoC should I be looking into (because they all have capsense), and how do I choose the correct MCU to start with? Is this decision based off the amount of electrodes that need to be sensed, and the number of I/O pins? There just doesn't seem to be much information or examples for trackpad design within PSoC Creator/PSoC Designer.

Any help pointing me in the right direction would be greatly appreciated!

[BragadeeshV · Accepted solution]

Hi jojo_4453281​,

Thank you for your interest in Cypress products.

We recommend you to use PSoC 63 BLE family products (4th generation CapSense) that supports both CapSense and BLE in a single chip. Or else you can also go with PSoC 4200 BLE products (3rd generation CapSense).

The PSoC 4S series - 4000S , 4100S and 4100 S Plus (4th gen CapSense) can also be used. But since your application needs a wireless transmission, you can interface it with the PSoC based BLE modules that Cypress provides.

PSoC 4 Trackpad examples:

https://www.cypress.com/documentation/code-examples/ce224821-psoc-4-capsense-touchpad-gestures

Trackpad Schematic / Layout: Refer to the design files of the flex PCB

https://www.cypress.com/documentation/development-kitsboards/cy8ckit-041-psoc-4-s-series-pioneer-kit

Regards,

Bragadeesh