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LMK00334: Can the output terminal of HCSL be changed from 50 ohm to 75 ohm?

hello_ao
Prodigy 100 points
Part Number: LMK00334

Because of the amplitude requirement of the receiver, the amplitude of 50 ohm of the termination is too small, I want to change it to 75 ohm termination

Is this OK? Does it affect the jitter？

  • 0
    TI__Genius 16845 points

    Typically for high speed design, the output impedance of the driver output impedance plus series resistance is matched to the trace and output termination. Does the receiver have integrated termination or biasing?

    Typically HCSL would only have this 50ohm termination at the driver. Alternatively it could be placed at the receiver, and it does not need to be placed in both locations.

    If there is no integrated termination at the receiver, you could start with R1=R2=25ohm and Zo = 75ohm.

    Kind regards,
    Lane

  • 0 in reply to Lane Boyd
    Prodigy 100 points

    The receiver have integrated termination and bias，and the channel is AC coupled

    I think it may be because of the small amplitude caused by the both termination,but the receiver cannot change it

    Because of the presence of AC capacitance, LMK00334 must be terminated, so if  R1=R2=22ohm and Zo = 75ohm is ok?

  • 0 in reply to hello_ao
    TI__Genius 16845 points

    What is the receiver termination and bias voltage?

    You could simulate using the IBIS model to analyze the signal integrity with your termination components, bias voltage, and transmission line to see if it meets your requirements

    Kind regards,
    Lane