Part Number: TMUXHS4212
Other Parts Discussed in Thread: HD3SS3212
Hi,
We are planning to use 3 TMUXHS4212 mux in cascaded configuration for 5Gbps differential high speed signals.
I came across the test report about cascade analog mux here.
If you look at the Fig 3.2 at the first page, the insertion loss is shown as -1dB at 5GHz.
First of all, this contradicts with the value given by datasheet of TMUXHS4212.
I do not think that we can achieve better insertion loss by cascading it.
Here you can see the insertion loss and return loss values given by the datasheet.
Then, I downloaded s parameter model provided by TI and simulated in Ansys/Electronic Desktop.
As shown in the picture below, it demonstrates insertion and return loss for single, 2 cascaded and 3 cascaded TMUXHS4212 muxes from top to bottom respectively.
As you can see, the values for insertion loss and return loss for single mux are close to the values given by datasheet.
However, 2 cascaded version does not match with the results in the TI test report at all.
As a note, I did not include any transmission line, via or etc.
Could you please explain me that why cascaded version in test report has better high frequency characteristics than the single version high frequency characteristics given in the datasheet?
If test report is correct, why my simulation output matches with datasheet but not with the test report?
Thank you.
Kind regards,
Derun
