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TRF3765: External VCO input to outputs frequency response (no PLL)

Dave Lewis93983
Prodigy 100 points
Other Parts Discussed in Thread: TRF3765

we would like to use the external VCO input to optionally distribute an external clock that can be > 4800 MHz to the TRF3765 outputs. In a prior case Mr. Hanish said....

Analog blocks do not exhibit these hard limits and tend to roll off functionality softly. For example, the electrical characteristics table in the datasheet describes a 9GHz limit where power output has rolled off by 20dB compared to normal, in-band levels.

http://e2e.ti.com/support/rf__digital_radio/high_performance_rf_modulators_pll_and_vco_products/f/224/t/219816

Is there more insertion loss information (plot, -3 and/or -6 dB bandwidth perhaps) and am I correct in that the TRF3765 can be used as a distribution buffer from the external VCO input?

many thanks

Dave 

  • 0
    TI__Mastermind 43910 points

    Hi Dave

    I'm checking to see if there is any additional data to help answer your question.

    So far I haven't found anything beyond the datasheet 9 GHz spec that Pete had mentioned.

    Best regards,

    Jim B

  • 0 in reply to Jim Brinkhurst1
    Prodigy 100 points
    Hi Jim,

    Thank you
    any update?

    I looked at the available kits and it looks like I could try to measure this on the TRF3765 EVM but seems like a bit of a waste to get an eval kit and set it up for only this (and we would have to measure with a power meter as we don't have a 10 GHz network analyzer)... Perhaps we could use the Eval kit for other things but we are more interested in integer mode (assume integer mode will be lower jitter and spurs?) and the TI web site says the TRF3765 board for integer mode is not available ?

    Thanks again

    Dave
  • 0 in reply to Dave Lewis93983
    Prodigy 100 points

    Any update?

    I checked internally and we (and our sister companies') test equipment does not currently  have frequency coverage  above 6 GGHz

    Thanks

    Dave

    PS: this is getting to be time sensitive so if no response I will try other channels to get a response tomorrow PM.

  • 0 in reply to Dave Lewis93983
    TI__Mastermind 43910 points

    Hi Dave

    My lab equipment is also limited to around 6 GHz.

    As noted in the datasheet, attenuation from the external VCO input to the LO outputs is around 20dB at 9 GHz.

    If you can provide your specific frequency range a colleage of mine may be able to provide additional information. However since this is not a datasheet spec, the information provided would only be typical data measured from a single device.

    Best regards,

    Jim B

  • 0 in reply to Jim Brinkhurst1
    TI__Mastermind 18065 points

    Below is a performance graph of the external VCO input to LO1M (with LO1P terminated) swept from 2 GHz to 12 GHz.  --RJH

  • 0 in reply to RJ Hopper
    Prodigy 100 points

    Thank you very much 

    That is what we needed.

    FYI (no action required) ...

    We are adding a lot of cost to our product to be able to operate with an external clock mode at higher frequencies and wanted to give an estimate of how high we will typically be able to go... . Sorry if this was an effort.

    Thanks again

    Dave