This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

  • Resolved

LMK04828: Clock output voltage

Prodigy 20 points

Replies: 4

Views: 411

Part Number: LMK04828

We are using LMK04828B in our board. We need 2400 MHz output clock. LMK04828B provides this clock frequency at VCO.  We can generate 75 MHz to 1200 MHz with desired LVDS output voltage level (400 mV p-p) using VCO clock. However when clock divider is bypassed in order to have 2400 MHz, output voltage level drops to 100 mV. How can we get VCO frequency at the output with desired voltage level?

  • Hello,
    I have assigned a responsible engineer to your post. He will get back to you soon.

    Kind regards,
    Lane

    ____________________________________________________________________________________

    To design your own Clock Tree solution, visit WEBENCH Clock Architect ​​​​

    More information Clock and Timing System products: http://www.ti.com/clock-and-timing/overview.html

  • Hello,

    It is true for your finding. Refer to the results TI measured in LMK04808, LVPECL could achieve higher amplitude than LVDS, especially in high frequency.

    Could you try LVPECL type?

    If the Vod on 2400 MHz is not enough, please look at LMK04832, which has CML drivers to get high Vod at high frequency like 2.5G/3.2G.

    Regards,

    Shawn

    ____________________________________________________________________________________

    To design your own Clock Tree solution, visit WEBENCH Clock Architect ​​​​

    More information Clock and Timing System products: http://www.ti.com/clock-and-timing/overview.html

  • In reply to Shawn Han:

    Thanks,

    Is there any document showing AC characteristics of LMK04032 or LMK4832? Otherwise we will try LVPECL type by modifying clock output termination circuit.
  • In reply to user5858002:

    Hello,

    It is LMK04832.

    Datasheet spec. highlights different Vods vs. frequencies.

    Best Regards,

    Shawn

    ____________________________________________________________________________________

    To design your own Clock Tree solution, visit WEBENCH Clock Architect ​​​​

    More information Clock and Timing System products: http://www.ti.com/clock-and-timing/overview.html

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.