3 Replies Latest reply on Aug 20, 2019 10:03 PM by AH_96

    Regarding MBR touch controller button size and more

    DiLo_4415146

      Hi,

       

      Greetings!

       

      We are leaving manufacturers of process automation equipment in India.

       

      Recently we have started working on CY8CMBR3108 MBR touch controller.

      We had few successful trials with the same and it works very well.

      However we are having some queries as below, request you to please help us on the same.

       

      1. However here we came to know that button size can not exceeds 15mm x 15mm.

      So is it possible to have button size bigger than 15mm x 15mm?

       

      2. Is it possible to make 1 large button by combining 2 or more buttons?

       

      3. Do you have MBR touch controller for touchpad / trackpad application?

       

      Here please note that we are referring AN90071 CapSense design Guide.

       

      Thanks in advance.

       

      Regards,

       

      Dinesh

      Design Manager

      Gladiance Automation Pvt. Ltd. Kolhapur

      India

        • 1. Re: Regarding MBR touch controller button size and more
          AH_96

          Hello DiLo_4415146

           

          1. The limiting factor is parasitic capacitance, Cp. The smartsense algorithm that powers the MBR3 device has a limitation of 45 pF. It is observed that with buttons larger than 15x15 mm, the parasitic capacitance, Cp is higher than 45pF and the device may fail to register a touch.

           

          2. No. This is not possible in MBR3 device.

           

          3. Trackpad/Touchpad is not supported in MBR3. The only supported widgets are buttons, sliders and proximity sensors.

           

          Thanks and regards
          Harigovind

          • 2. Re: Regarding MBR touch controller button size and more
            DiLo_4415146

            Hi,

             

            Greetings!

             

            Thank you for prompt reply.

             

            let me explain you in more detail.

             

            1) Product A

             

            It is a button cell powered bluetooth low energy user interface with a area 42mm x 42mm assigned for touch buttons.

            We wish to place four touch buttons as per attached sketch. We will manage in the software this four touch buttons in such a way that either the entire area ( touch button 1, touch button 2, touch button 3, touch button 4 ) as one button or four individual buttons or two buttons ( touch button 1+touch button2, touch button3+touch button 4). Since we are keeping the button sizes and ground clearance s within the specifications given. We strongly feel that with above arrangement as four small buttons, two medium button or one big button will work. Please comment.

             

            2) Product B

             

            This is also button cell powered bluetooth low energy device. Can we use the button size other than 15x15mm ( 225 sqmm ) keeping the area within 225 sqmm. e.g.  20mm x 10mm.

            Please clarify.

             

            If the answer to 1 and 2 is NO then please suggest suitable device which can operate on button cell and it is a low cost.

             

            Regards,

             

            Dinesh

            Design Manager

            Gladiance Automation Pvt. Ltd. Kolhapur

            India

            • 3. Re: Regarding MBR touch controller button size and more
              AH_96

              Hello DiLo_4415146

               

              1. Product A-

              MBR3 cannot be programmed for such an operation. It can only be configured to detect the button press using the smart sense algorithm. Please consider using the PSoC devices which allow programming the chip for additional operations. It also allows manual tuning for better sensitivity when parasitic capacitance is higher.

              You can use the PSoC 4000 device which have pin compatibility with MBR3 devices (in case the layout is already designed). The PSoC 4000S, 4100S and 4100S plus have the latest CapSense IP for better performance and advanced features.

               

              2. Product B-

              Yes. This understanding is correct. The area is the factor contributing to the parasitic capacitance.

               

              Thanks and regards
              Harigovind