Capsense operation with conducting sheet

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
BhSa_4078721
Level 2
Level 2
10 replies posted 10 questions asked 5 replies posted

Hi,

I am using PSOC4 part.

Generally we place a non conducting material on capsense pcb as overlay...Will it work if very thin conducting material place on pcb ??

Or any suggestions, recommendation for such assembly...

0 Likes
1 Solution
BragadeeshV
Moderator
Moderator
Moderator
First question asked 1000 replies posted 750 replies posted

Hi BhSa_4078721​,

It is not recommended to place any conductive material as overlay on top of the sensors for the following reasons:

1. If the metal object is floating and is not grounded, then accidental grounding of the metal would lead to raw count saturation and is a potential false trigger.

2. If the metal is ensured to be grounded at all times, then the sensitivity of the button would drastically decrease owing to increased Cp.

If you are looking for metal over touch applications (metal overlay), we recommend you to look for Inductive sensing based touch detection that we offer. For more information see Inductive sensing app note.

https://www.cypress.com/documentation/application-notes/an219207-inductive-sensing-design-guide

Regards,

Bragadeesh

Regards,
Bragadeesh

View solution in original post

0 Likes
1 Reply
BragadeeshV
Moderator
Moderator
Moderator
First question asked 1000 replies posted 750 replies posted

Hi BhSa_4078721​,

It is not recommended to place any conductive material as overlay on top of the sensors for the following reasons:

1. If the metal object is floating and is not grounded, then accidental grounding of the metal would lead to raw count saturation and is a potential false trigger.

2. If the metal is ensured to be grounded at all times, then the sensitivity of the button would drastically decrease owing to increased Cp.

If you are looking for metal over touch applications (metal overlay), we recommend you to look for Inductive sensing based touch detection that we offer. For more information see Inductive sensing app note.

https://www.cypress.com/documentation/application-notes/an219207-inductive-sensing-design-guide

Regards,

Bragadeesh

Regards,
Bragadeesh
0 Likes