6 Replies Latest reply on Nov 19, 2020 6:12 AM by user_4340301

    CYPD3171 powerbank - problem in production.

    user_4340301

      Dear Cypress,

      During production of powerbanks (with CYPD3171 as USBC PD 60W controller) we found problem that we hadn't noticed before:

       

      One of three devices cannot charge. After connecting charger with correct PD profile (or even simply 5V) CYPD3171 locks up and appears to be dead. After some time, when BMS disable power supply (because of discharging) and when charger is connected again, CYPD3171 works correctly. We are afraid that our clients can have the same situation. Can You check our configuration file for errors? I am adding also schematic.

       

      Best regards

      Lukas

        • 1. Re: CYPD3171 powerbank - problem in production.
          MallikaK_41

          Hi Lukas,

           

          >> Can you please specify what do you mean by "one of the three devices cannot charge"?

          Do you have 3 devices with the same schematic and firmware running and only 1 of them is behaving abnormally?

           

          >> May I know if you have PD log Analyzer with you? If yes, please share the cc logs.

           

          Best Regards,

          Mallika

          • 2. Re: CYPD3171 powerbank - problem in production.
            user_4340301

            Dear Mallika,

            for 500 devices produced, 130 of them have a problem.All of the devices have the same layout and PCB.

            The CYPD3171 is in this device as a DRP (device has a battery pack). Problem is when battery is low. Until the charger is onnected, everything works correctly. After connecting the charger, the device doesn't charge. We observed this on USBC-USBC dongle. and it looks like there was no communication. We had 6 device with this problem and we fixed all of them by reseting power supply. Now that 6 devices are working correctly, but we have to be sure, that this problem will not appear in future.

             

             

            Yes we have PD log analyzer, but we don't have any logs from these 6 devices. We are waiting for rest of devices with this issue.

             

            Best regards,

            Lukas

            • 3. Re: CYPD3171 powerbank - problem in production.
              MallikaK_41

              Hi Lukas,

               

              >> Do you have the VBUS_IN_DISCHARGE, VDDD and CC waveform when the issue had occurred?

              It would be easier to find the root cause if you would be able to provide the traces or the cc logs when the issue is occurring.

               

              >> What do you imply by resetting the power supply?

               

              Also, you can try disabling the OVP.

               

              Regards,

              Mallika

              • 4. Re: CYPD3171 powerbank - problem in production.
                user_4340301

                Dear Mallika,

                we don't have the devices having the issue yet(we are waitng for delivery), so I can't get any waveforms or logs. We also cannot  dissassembly the devices, we can only change software through USBC.

                This is a powerbank and by resseting the power supply I mean that, I left the device until the BMS disable power supply on the PCB.

                I will try to disable OVP.

                Best regards

                Lukas

                • 5. Re: CYPD3171 powerbank - problem in production.
                  ShifangZ_26

                  Hi Lukas,

                   

                  Could you please kindly share the schematic (You just need share CCG3PA relates circuits) in this thread and help to measure the power sequence of true environment of VDDD, VBUS_IN_DISCHAREG, VCCD?

                   

                  Feel free to contact local FAE with this issue to get further support.

                   

                  Best Regards,

                  Lisa

                  • 6. Re: CYPD3171 powerbank - problem in production.
                    user_4340301

                    Dear Lisa,

                    Here is a schematic of a converter that is connected to CYPD3171. More schematic of the device I can't upload here.

                    When the devices arrived to us, I will try to measure voltage at the points You listed above.

                    Best regards,

                    Lukas

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