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TMUX136: Impedance matching

Genius 13729 points
Part Number: TMUX136

Hi Experts,

Customer wants to use either of the following in a matched impedance context. What is the impedance of these devices?

  • TMUX136RSER

We are looking to have an impedance around 20 ohms. Is there a device that would work for this?

Thank you.

Regards,
Archie A.

  • Hi Archie,

    Did you mean to provide more than one device? I only see the TMUX136. 

    Since our analog muxes are passive devices, we do not have an input or output impedance of the Sx pins and Dx pins. For the TMUX136, we do have an Ron, which is 4.6Ω(typ), which will be the effective resistance that you will see from S to D on your signal when the switch is on.

    Thanks!

    Alex

  • Hello Alex,

    We have a follow-up question about the TMUX136RSER. In the datasheet, it is mentioned that the switching time is 600ns. What I am wondering with this number is if it is a dead time or a switching skew? In other words, I would like to operate the switch at a 50% duty cycle between A and B, what is the maximal frequency of this switching (the operation with a delay would not be critical to me).

    Regards,
    Archie A.

  • Hi Archie,

    Switching time is different from skew. We spec skew time in the datasheet as 20ps. I believe you would classify this 600ns as a dead time - no connection during this 600ns range. If the period of one cycle is twice the switching time when the duty cycle is 50%, then the max switching frequency would be 833 KHz. As always, I recommend modeling this to ensure proper operation. 

    Thanks!

    Alex