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DS110DF111: Does DS110DF111 meet SFP specification about input / output differential amplitude?

K.Yaita
Guru 29720 points
Part Number: DS110DF111

Hi Team,

The datasheet shows the following. 



On the other hand, I found the SFP specification as the following.
RD-/+ (differential receiver outputs) : 370mV~2000mV
TD-/+ (differential transmitter inputs) : 500mV~2400mV

It seems differential voltage of CML RX inputs and CML TX outputs of DS110DF111 can't cover the range of SFP specification.
Is it possible to connect directly to SFP?

Best Regards,
Yaita

  • 0
    TI__Guru* 93670 points

    Hi Yaita-San,

    DS110DF111 meets SFF-8431 specifications. This spec complies with 10G and 1.25Gbps operation. As noted in SFF-8431 specifications, INF-8074i 2000mV input differential is not considered practical for modern 10Gbps receivers. Additionally INF-8074i spec recommends value between 500-1200mV differential for best EMI performance.

    Regards,, Nasser

  • 0 in reply to Nasser Mohammadi
    Guru 29720 points

    Hi Nasser-san,

    Thank you for your support.

    >As noted in SFF-8431 specifications, INF-8074i 2000mV input differential is not considered practical for modern 10Gbps receivers.
    I understand 2000mV(max) of SFP module Receiver output is not considered practical.
    What do you think about 370mV(min) of SFP module Receiver output?
    Is seems DS110DF111 doesn't support it.



    Best Regards,
    Yaita

  • 0 in reply to K.Yaita
    TI__Guru* 93670 points

    Yaita-San,

    Yes based on data sheet that's what it looks like. 

    Can you please send me email and provide more information about this customer application.

    Regards,, Nasser

  • 0 in reply to Nasser Mohammadi
    Guru 29720 points

    Hi Nasser-san,

    Thank you for your kind reply.
    I will send the application information to you later.

    Best Regards,
    Yaita