3 Replies Latest reply on Jun 16, 2019 8:51 PM by ShifangZ_26

    VBUS_C_CTRL on CYPD4155-96BZXI

    dapec_2892156

      I'm searching for a setting to prevent the VBUS_C_CTRL pin from enabling when my system is attached to a PC. I have my "Sink PDO 1" setup for fixed 15V, this is the voltage that I want to power up my system, not a low current PC USB port at 5V. I am not able to disable "Sink PDO 0" or change its voltage to 15V by the EZ-PD Configuration Utility.

      Is there a setting within the EZ-PD Configuration Utility to allow me to prevent 5V from powering up my system? meaning, don't enable VBUS_C_CTRL when a higher voltage supply has not been negotiated.

        • 1. Re: VBUS_C_CTRL on CYPD4155-96BZXI
          ShifangZ_26

          Hi ,

           

          1. The 5V sink PDO shall be included in. Since all of Type-C negotiation need settle it based on 5V voltage, the contract can be go back to 5V if the high and best voltage cannot be supplied by power supplier.

           

          2. The way to achieve your requirement is customize the firmware code with below@function void psnk_enable (uint8_t port) :

           

          Best Regards,

          Lisa

          • 2. Re: VBUS_C_CTRL on CYPD4155-96BZXI
            dapec_2892156

            This worked, but only if a PC is connected and a power supply is never connected. If I connect a power supply, then disconnect it and connect the PC, then VBUS_C_CTRL once again starts to be enabled. I assume this is because a contract has been negotiated and that remains in the "contract" property. Is there another property that would work, maybe "pd_get_vbus_adc_level"?

            • 3. Re: VBUS_C_CTRL on CYPD4155-96BZXI
              ShifangZ_26

              May I know the details CC log and VBUS, VBUS_C_CTRL, CC1/CC2 waveform?

               

              From your description, it seems the sink_fet_on have been called on some conditions, but it is not called by psnk_enable? Am I correct?

               

              Best Regards,

              Lisa