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TS5A3166: TS5A3167 vs TS5A3166 bandwidth and rise times

Part Number: TS5A3166

Hi, 

I'd like to use TS5A3167 but I have question about bandwidth of TS5A3166 versus TS5A3167
In the overview page, both are listed as 200MHz
However, in datasheet itself of 3167 it says only 150MHz , while 3166 is 200MHz.

 My second question is:  why BW is 25% lower for the ..67 compared to the ..66 given similar Rds_ON and Cd/Cs values ?

  • Sebastien,

    The TS5A3167 and TS5A3166 devices should have they same bandwidth since the only difference between them is the logic control.  

    It looks like in 2005 the datasheet had the bandwidth for both devices at 200MHz for all supply voltages.  In 2012 the datasheet was revised to the way the bandwidth is listed today.  I do not see any notes of a reason for this change.

    I went and looked at the original characterization data and the plots suggest that 200MHz is supported by these devices.  

    I will log this into our datasheet error backlog.

    What is your application that you are sensitive to 50MHz performance reduction?

    Thank you,

    Adam

  • In reply to Adam Torma:

    Hi Adam,

    The custmer plans to use it to pass a digital 3V3 signal from one device to another.
    Signal can change direction and no additional delay is important, so that's why he wants to use this analog switch.
    The frequency of the digital signal is only 40MHz, but what matters is that the rise/ fall times are not degraded by more than, say 1-2ns.
    Now this should be dictated by the Rds_on & Cds capacitance, which is almost identical for the ..66 and 67 devices. In his opinion, the BW should be solely dictated by this RC, so he thinks there's no real BW difference between both devices. That's why he would like to understand if there's something more behind this BW parameter than just the RC effect, or if the owner of the datasheet just took more margin in the spec for the 67 but that it's in fact identical to the 66 device.

    Thank you,

    Sébastien
  • In reply to Sebastien Rougeot:

    Sebastien,

    Thank you for sharing more information.  You are making correct assumptions that the TS5A3316 and TS5A3317 should have the simliar bandwidth.  You are correct, for a rough calculation you can use the Rds_on & Cds capacitance to predict and calculate your rise and fall times/bandwidth.  To have the best calculation of bandwidth it would be good to have an s-parameter model of the switch because the RC will vary across frequency and voltages.    

    Here is an additional link about bandwidth and rise time relationship. 

    Bandwidth /rise time rule of thumb relationship. 

    Thank you,

    Adam