1 Reply Latest reply on Dec 21, 2017 11:49 PM by gani

    Curve shape slider design

    user_50100167

      Hello,

       

      We are intended to place capsense slider segments in curved shape  ( as shown in attached file ) and have below queries.

       

      1> Is there any guideline document available to place slider segment along curved path ?

      2> Is it must to have all slider segments in equal dimension ?

      3> Is there any requirement on width of the ground mesh around slider segment ? As we intend to place slider close to board edge, and have very small room for ground mesh on one side.

      4> Can slider trace run parallel with 10 mil clearance in between ( No ground mesh in between them) ?

      5> is it Ok to place capsense IC on one side of slider , as shown in image ?

       

      Thanks,

      Vishal

        • 1. Re: Curve shape slider design
          gani

          Hi Vishal,

           

          Please find the answers below:

           

          >>"1> Is there any guideline document available to place slider segment along curved path ?"

           

          --> There is no special document for specifying the curved slider. Our basic recommendation is to keep all the sensing elements identical for linearity between finger position and the actual output. So you can go with the recommendations of linear slider only.

           

          >>"2> Is it must to have all slider segments in equal dimension ?"

           

          --> Yes. Otherwise the output count will not be in linear with the position of the finger.

           

          >>"3> Is there any requirement on width of the ground mesh around slider segment ? As we intend to place slider close to board edge, and have very small room for ground mesh on one side."

           

          --> The air gap between the surrounding mesh and the CapSense sensors should be equal to the thickness of the overlay. And the dimensions of the hatch pattern is 7 mil width and 45 mil spacing in top layer and 7 mil width and 70 mil spacing in the bottom layer.

           

          >>"4> Can slider trace run parallel with 10 mil clearance in between ( No ground mesh in between them) ?"

           

          --> The recommended CapSense trace to trace clearance is 0.25 mm. Converting to mil it is 20 mil.

           

          >>"5> is it Ok to place capsense IC on one side of slider , as shown in image ?"

           

          --> It is not recommended to place the IC exactly under the CapSense sensors or traces in the other layer. Other than this area you can place it anywhere.

           

          Thanks and Regards

          Ganesh