3 Replies Latest reply on Oct 30, 2019 8:11 AM by AH_96

    sensor connections in kit

    LaKa_4300241

      Hi

      I have connected the sensor we designed with a sensing loop and the ground loop.

      The sensor PCB has a shield at the bottom so that it should not sense any thing from bottom.

      But in our case the sensor is sensing at the bottom. I have attached the design pic in the mail.

       

      do you have any suggestions that i have to change the pin connections.

      Any suggestions for the sensor cord that we have to use for better sensing.

       

      pin connections:

       

      sense loop to pin 1.4

      shield to pin 4.0

      ground loop to GND.

      and sensor cord i used is PURtronic-D 3*0.14mm

      I have attaches the snsorcord connections pics also to the mail.In that connections I have a doubt that the shield of the sensor cord is connected to the GND or pin 4.0 on the kit. The small inner wires in sensor cord is connected to GND pin and the pin 1.4.

      is the connection rite or wrong.

        • 1. Re: sensor connections in kit
          AH_96

          Hi LaKa_4300241

           

          While checking sensor's activity in the bottom layer, please make sure that you are not touching the wires connecting the sensor to the kit. Cypress recommends using a 7-mil thick PCB trace for connecting CapSense traces. The thicker the wire, the more sensitive the wire becomes. Hence it is possible that the wire is causing the increased signal and not the proximity sensor.

           

          Also please share a picture of the sensor also so that we can understand the setup better.

           

          "I have a doubt that the shield of the sensor cord is connected to the GND or pin 4.0 on the kit. "

          Can you please elaborate this point? You can probe the shield pin to see if the shield hatch is getting charged and discharged. Please share a screenshot of the oscilloscope output.

           

          Thanks and regards

          Hari

          • 2. Re: sensor connections in kit
            LaKa_4300241

            Hi

            The shield of the sensor cord is connected one end to the pin 4.0 not to the ground and other end to the shield of the sensor.

             

            This is a loop senor with ground loop and sense loop. It had a hatching shield at the bottom.

            • 3. Re: sensor connections in kit
              AH_96

              Hello LaKa_4300241

               

              Please send a picture of the wire loop that you are using as proximity sensor. Please consider designing a PCB with a trace loop as proximity sensor. It is only in this case that a shield will help in not detecting on opposite side.

               

              A picture of the sensor will help us greatly in understanding the setup.

               

              Thanks and regards

              Hari