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TMUX136: S-Parameter Port Mapping

Andrew Goett12
Prodigy 70 points
Part Number: TMUX136


Hello, 

I downloaded the S-Parameter files for the TMUX136 ( http://www.ti.com/lit/zip/scdm209 ) and have integrated them into some simulations for a future design. I had a question about how the ports of this model map to the actual pins of the device. I could be overlooking some documentation, but I was unable to find any info on this mapping. 

The S parameter file is a single 4 port model. This leads me to believe that each port is one of the following pins on the device (ie A1 = Port 1, B1 = Port 2, A2 = Port 3, B2 = Port 4). I just want to confirm that this is the case. 


Another question I have is: are there S-Parameter files for the signal behavior between COM1 and A1 or B1, and COM2 and A2 or B2? Is the switch intended for usage in this way (ie passing signals from COM to an output, versus passing signals strictly from A to B. 

Thanks!

Andrew

  • 0
    Prodigy 70 points
    Another question I forgot to ask - why do the S-Parameter files for this component not line up with the characterization shown in the datasheet?

    S21 is measured in the datasheet at -3.317dB at 6.6139GHz (Section 6.8, Figure 2). In the S-Parameter files, S21 is -5.4dB at 6.31GHz, and the model hits -3.5dB from at 4.08GHz (this is a -3dB change from the S21 attenuation near DC (-0.5dB)).

    Thanks again, I appreciate any insight I can get into this part.
  • 0 in reply to Andrew Goett12
    TI__Mastermind 45595 points
    Andrew,

    The intended signal path for the TMUX136 is COM to connect to either A or B. The device will connect COM to A if SEL pin is logic low and COM to B if SEL pin is logic high.

    The s-parameter model is for the path from COM to A or COM to B. For example port 1 will be COM and Port 2 will be A or B.

    The bandwidth plot in the datasheet shows the measurement of the device using careful testing techniques to make sure the measurement is from the TMUX136 device only and not any board, trace, or connector parasitic.

    The s-parameter model was simply created from the measurement on a PCB and the difference is the added attenuation from impedance discontinuities in the connectors, board trace, etc.

    Thank you,
    Adam
  • 0 in reply to Adam Torma
    Prodigy 70 points
    Thank for the fast reply Adam, this resolved my issue.