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LMK05318: LVPECL output configuration

Part Number: LMK05318

Hi team,

My customer is using LMK05318 now. Currently the output is LVPECL. We want to check whether we need to put terminator resistors. From the datasheet, we may not need to put any terminator resistors. Thanks.

  • Hello, 

    On LMK05318, LVDS, CML and LVPECL outputs are all similar. They require AC-coupling and 50 ohm to ground resistance. If the resistance is provided on the receiver side then that is sufficient. 

    Thanks and regards,

    Amin 

  • Hi Amin,

    if our device source current is 8mA, the single end voltage will be only 400mv, the differential voltage will be 800mv. Which is not aligned with normal LVPECL spec (800mv single end). Could you please share your comments? Thanks.

    BTW: What's the risk if the customer put the external pull down resistors? Thanks.

  • Hi Frank, 

    The specs are SE - 800mV, differential double that. This is aligned with normal LVPECL swing. 

    Recommendation is no pull down resistors. AC coupled - 50 ohm loading. 

    Thanks and regards,

    Amin