• RE: [LTPoE LT4293] Implementation and configuration when LT4293 works Ultramode

    Hi HS,

    UltraPWR is a specific mode of the LTC4279. It should only be used in a closed system. It will aggressively power any valid PDs, and it will set the current limit to 2950mA typical. The LT4293 will identify an LTC4279 in UltraPWR mode as an LTPoE…

  • RE: LT4320 implementation with LT4293


    the LT4321 features these important facts:

    • Fully Compatible with IEEE 802.3 Detection and Classification
    • IEEE 802.3 Compliant When Paired with a Powered Device (PD) Controller
    • Works with 2-Pair and 4-Pair PoE Applications
    • Compatible with PoE,…
  • RE: [LT4293] Inquries regarding aux power, ground and miscellaneous things

    Good Day HS,

    The LT4321, LT4293, and the input side of the isolated DC/DC converter will have their ground pins connected. The output of the DC/DC converter will have a separate ground.

    About the choke filter, are you talking about this filter (boxed…

  • Inquiry about LT4293 PD


    My customer has two questions for LT4293 PD application.

    1. The description section of the LT4293 data sheet states that LT4293 includes undervoltage lockout. But there is no further explanation.

        Could you please provide the operation condtion of…

  • DC2911A/LT4293: PoE demotion/denial unclear

    I'm studying the DC2911A datasheet (Evalboard for LT4293).

    Table 4 lists the interoperability between PSE and PD. The blue shaded region is labeled as "PD has been demoted or denied power".

    How will that demotion work in practice? Will the…

  • Overvoltage Protection over 100V for the LT4293


    My customer wants to design a IEEE802.bt complient PD module with overvoltage protection function for over 100V using the LT4293 + the LT4321.

    Could you please provide any information fot the above application ?


  • LT4293 PD Operation with Lower Class PSE Devices

    I am looking into using the LT4293 for use within a design; however, I am confused about two issues.

    Looking at Table 6 in the LT4293's datasheet (LT4293 Interoperability), it shows that 802.3 lower class PSE devices will agree upon demotion for higher…

  • LTC4279、LT4293输出波形问题

    使用LTC4279做PSE端48V供电,LT4293做PD端,连接后测量VPP和VPN两端电压发现如下图波形,之后一直是如此循环状态是什么原因? ,PSE原理图如下图所示 ,PD原理图如下图所示

  • RE: Can the LT4295, LT4293, LT4275A and LT4276A handle dual-signature in PD applications?


    IEEE 802.3bt defines two PD topologies: single-signature and dual-signature. Single-signature PDs present a valid detection signature on both pairsets, while dual-signature PDs present separate detection signatures on each of the two pairsets.…

  • 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…