• RE: LT4275 Cannot deliver power and ethernet signal together


    To understand your problem; ethernet data stops working with the LT4275. Are you using an LT4275 demo board, or is this a custom design? Same question with the ENC28J60, is this a custom design? A schematic and block diagram would be very helpful.

  • Will LT4275 be supportive for PSE switches other than linear make?


    I have been working with power over ethernet project and using PD -LT4275. Tested PD board with PSE - 1815A-D and is working well. I would like to know whether the PD will support of other PSE like cisco pse switch. Or LT4275 will works only compatible…

  • Power-ON problem of LT4275A - LTPoE++ with DC1815A-D-ND with load above 30W


    I am working with power over ethernet and using PD LT4275A with DC1815A pse. The circuit seems to be working properly at least till 70W. But am facing a problem at startup.If the Power demand at the start of board is higher than around 10-12W, the…

  • PD Design Query for UltraPWR Mode of LTC4279


    My customer wants to implement PoE system up to 123W using the LTC4279's UltraPWR mode.

    However, ADI's PD devices only support up to 90W(LT4275, LT4276, LT4293...).

    Could you please provide reference material for a PD design that supports 123W…

  • LTC4266A-3 fail to output 70w


          We  design POE++ with LTC4266A-3 , but now the output can be only around  30w  with 90w PD (LT4275), can you kindly help to advice,

    1. How can i get the software programming documentation.

    2. Things to improve with the design...

  • RE: POE LTC4271/LTC4290 -SR-70860-Q5B2L

    Hi Suleyman,

    What PD are you testing with, and have you tested with different boards like our LT4275 demo circuit?  Can you provide a schematic for your PSE board, and if you built the PD board, the schematic for that as well? Which LTC4290 are you using…

  • RE: LT4275 cannot deliver power above 30W eventhough designed for LTPoE++

    Check out LTC4279, Single Port PoE/PoE+/LTPoE++ PSE Controller. DC2541A supports up to 90W LTPoE++ PDs.

    Best Regards,


  • RE: LTC4266 and POE specs info

    As usual i answer my own questions when i decide to read the datasheet in details and not the scattered informations on google.

    But correct me if i am wrong :

    -I want to use a LTC4266 with a 54V/200W external power supply

    -The distant device (<12.95W…