Design touchpad with hatch fill as shield electrode for water tolerance

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dabo_4430311
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Are there any design files or guides to build a trackpad with hatch ground connected to shield electrode for water tolerance? any general suggestions?

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1 Solution

1: You only need to connect the sensors of rows and columns both to the sensor pin, don't need to let them have any physical connection of shield. It should be configure it the CSD component like below:

pastedImage_0.png

2:  The answer of your second question: You should clarify your second question more clearly, if you means that whether needed to add one more layer to act as the shield, it is not needed.

3: You can refer to our PSoC4 trackpad board hardware design:

You can search the CY8CKIT-040 PSoC 4000 Pioneer Kit, download and install it, then you can find the touchpad shield file in the installation catalog like the routing :

C:\Program Files (x86)\Cypress\CY8CKIT-040 PSoC 4000 Pioneer Kit\1.0\Hardware\TrackpadShield

4: Hope it can be helpful for you!

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5 Replies
LinglingG_46
Moderator
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500 solutions authored 1000 replies posted 10 questions asked

Hi davide bondavalli,

Normally, we will design a touch pad like below:

pastedImage_0.png

You can configure the inactive sensor connected to the Shield.

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The circle has just image displaying purpose? It is not part of the traces right?

So there wouldn’t be an hatched fill around the trackpad but I should pitch some sensors inside of the trackpad and connect them to the shield?

Sent from my iPhone

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The circle has just image displaying purpose? It is not part of the traces right?

Yes, I only want to show you the pitch.

So there wouldn’t be an hatched fill around the trackpad but I should pitch some sensors inside of the trackpad and connect them to the shield?

You don't need to add the hatch fill around the trackpad sensor.

The CSD IP scans sensor one by one, you can configure the sensor to shield (which is not scanning). You don't need to add any other sensor.

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Thank you for the great and precise answer,

To recap:

I should design a trackpad with connections of rows and columns both to the shield and to the sensing signal, so to drive them with one signal or the other according to if I’m scanning that pad or not thus making them active or inactive dynamically?

Or can I just do that with one connection and change the interpretation of the reading? Because I read that the Csd takes both the signals as inputs

Second point is about the shield ground hatch on the back of the touchpad, should I cannot that one too to the shield further then connecting the inactive pads? Is it strictly necessary?

Sent from my iPhone

0 Likes

1: You only need to connect the sensors of rows and columns both to the sensor pin, don't need to let them have any physical connection of shield. It should be configure it the CSD component like below:

pastedImage_0.png

2:  The answer of your second question: You should clarify your second question more clearly, if you means that whether needed to add one more layer to act as the shield, it is not needed.

3: You can refer to our PSoC4 trackpad board hardware design:

You can search the CY8CKIT-040 PSoC 4000 Pioneer Kit, download and install it, then you can find the touchpad shield file in the installation catalog like the routing :

C:\Program Files (x86)\Cypress\CY8CKIT-040 PSoC 4000 Pioneer Kit\1.0\Hardware\TrackpadShield

4: Hope it can be helpful for you!