4 Replies Latest reply on Nov 23, 2017 5:42 AM by user_2504551

    CY8CMBR2016 Don't Works



      I making a project with the CY8CMBR2016 controller, I followed the recommendations of datasheet, the button have 8 mm diameter and the more long trace have 85 mm, the Cpin with 2.2nF, the calculate parasite capacitance the bigger have 17pF,  the serie resistor with 560R, the resistor for Out_Sel for select encoding 4-bit with resistor 1K5, ARST with resistor 1K5, CMOD Cap with 2.2nF, Scan with resistor 1K5 and Sensitivity resistor 1k5 for medium, in debug with resistor of 5K6 and power supply with 3V3, some time the PCB alone the pin INT going up alone without anybody touch, Some people have some idea what happened. On the pin 4-bit don't have signal.


      My overlay have 2mm but doesn't works of 0 until 2 mm


      OBS the other chip on the PCB are the NFC controller but are disable!









      Best Regards

        • 1. Re: CY8CMBR2016 Don't Works

          hi cleber,


          i too faced similar issue while working with cap_sence last year. all remembered is that Cmod capacitance and resistance value in series wih need to be troubleshooting.

          i din't remembered exact values i have used but but the underlying fact is that when you increse the series resistance (5.4 k in your case) more drop will be across the resistance leading the config hyper-sensitive (unstable). i think 560E is ideal value you may vary it for tuning but it should not be in more than 1K .


          try reducing the value of resistance. if this is making the it less sensitive or if you are not getting proper results you may try incread

          sing the C_mod value arond 4.7nf (but this will increase the sensing time)


          if you want details about the configuration used please let me know i will get that from my archives.



          1 of 1 people found this helpful
          • 2. Re: CY8CMBR2016 Don't Works


            Thanks for answer.


            I try change of value Cmod about 1nF, 2,2nF, 3nF, 4nF e 10 nF did not Work, I change resistor ARST for to GND, 1K5 e 5K Not Work, the output Select is Encoded 4 bit output with 1K5 to GND, Scan are 1K5, Sensitivity with 1K5, try 5K and VDD/Floting but not Work.


            I install the BCP and MultiChart tools but not Work, I don't see any waveform, I put the command RX8 and nothing, but the pin Debug TX have waveform in oscilloscope "see image" before this the INT pin going up some times and now nothing.


            Does witch i damage the chip controller? I don't believe because are sending bytes in debug pin!


            In design layout estimator I put the data and PASS.








            See wave form in Debug Pin.


            The number of vias that have on layout are maximum with two, and some sense have one. I don't pass two vias.


            How the best tools for debug this Chip controller, have some other for this chip?


            Remember the other chip in PCB are disable.


            Have some other features for troubleshooting tools for fix and debug?


            The value is hard and precision?


            See video    YouTube



            • 3. Re: CY8CMBR2016 Don't Works



              Today I got change the C_pin capacitor then is get work ( I take off the 2.2nF from C_pin wich in Datasheet talk about is mandatory for work, but with C_pin does not work), the INT pin going high when I touch a button, have good sensivity, but I dont have any information in encoded 4 bit in any pin, the pin still in GND when I touch any button, the resistor for select output are 1K5 5% for encoded 4 bits.

              Have some others thinks for select output? Thats pins for output is a Open Drain?



              Have a lots of revision and others white paper obsolete.

              In BCP tools was don't work.  I try the put command line but in the chart don't see nothing without waveform.



              • 4. Re: CY8CMBR2016 Don't Works



                Thanks, for all


                After wich calculated the capacitor for Cmod and put correct resistor for select output, is are works really fine ever. The multi Chart tools works very well, each button works very fine. Are robust chip for controller touch capacitive.