3 Replies Latest reply on Aug 13, 2015 9:13 AM by Carlos_A

    I210 Power using Single 3.3V rail

    asiwarski Community Member

      Hi,

       

      I have a question...If I'm designing a CCA using the i210, single 3.3V supply.   What is the worst case current draw I would expect on this rail operating 100Mb/s.  Section 11.5 in the datasheet shows current consumptions but it lists using external power supplies.  The table shows 75.5mA but I would expect this to increase if using the iSVRs as these are powered from the 3.3V rail.  This board would operate from -40 to 85C.  I'm trying to size my 3.3V power supply for the I210. 

       

      Also, the iSVRs for the 1.5V and 0.9V should follow the parameters listed in table 11.3.1?  Basically, if I'm using the single 3.3V rail option,  I don't have to worry about sequencing and rise times for the other two rails - correct - as this is designed into the part?

       

      Cheers,

       

      Andy Siwarski

        • Re: I210 Power using Single 3.3V rail
          Carlos_A Brown Belt

          Hello Andy,

           

          In order to better understand your consultations, could you please tell us if you are using the Intel(R) Ethernet Controller I210-AT, Intel(R) Ethernet Controller I210-IT, Intel(R) Ethernet Controller I210-IS, Intel(R) Ethernet Controller I210-T1, or Intel(R) Ethernet Controller I210-CS?

           

          On the other hand, the Intel(R) Ethernet Controller I210 supports generating the 1.5V and 0.9V power supplies from the 3.3V supply by using an on-chip Switching Capacitor Voltage Regulator (SVR) control circuit, which requires only an external capacitor component. You can confirm this information in section 3.6, on page 83 of the Intel(R) Ethernet Controller I210 Datasheet.

           

          In case that you want to implement the suggested design, please refer to the electrical specifications stated in Section 11.6.6, on page 795 of the cited Datasheet.

           

          Please let us know if this information is useful to you.

           

           

          Best Regards,
          Carlos A.

            • Re: I210 Power using Single 3.3V rail
              asiwarski Community Member

              Hi Carlos,

               

              I'm using the Intel(R) Ethernet Controller I210-IT.   I would use the single 3.3V option as recommended by the datasheet.  Looking at 11.6.6, am I sizing my 3.3V supply for 350mA worst case (175mA for each 0.9V and 1.5V?

               

              Looking at the reference schematic, page 9, it's showing the TPS63030 as Calculated Power supply as Iout Max = 350mA for V3p3_LAN so perhaps that is what I need to use.

                • Re: I210 Power using Single 3.3V rail
                  Carlos_A Brown Belt

                  Hello Andy,

                   

                  Thanks for your update.

                   

                  You are correct from the worst scenario perspective. By the way, it seems to match with the third party High Efficient Single Inductor Buck-Boost Converter specification mentioned.

                   

                  Please let us know if there is anything else we can help you with.

                   

                   

                  Best Regards,
                  Carlos A.