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LMV761: Shutdown to output Hi-Z delay?

dB
Prodigy 60 points
Part Number: LMV761

The data sheet (SNOS998I – OCT 2015) specifies a typical value for Ton (Turnon time from shutdown) for various conditions.

Is Ti able to provide a (max & typ) figure for the time from shutdown (/SD) failing to the output going into the high-impedance state?

Thanks

dB

  • 0
    TI__Intellectual 1740 points
    Hi dB,

    Unfortunately, we do not have the max or typical timing plots for shutdown. What we can do is take this measurement on 5 devices and provide the average for you. Please let us know if you would like this. We should be able to get back to you in about 10 business days.

    Regards,
    Jaskaran
  • 0 in reply to Jaskaran Atwal
    Prodigy 60 points
    Hi Jaskaran,

    Thanks for the quick response.

    Yes, please go ahead with the measurements. I'd appreciate if you could provide the individual test results in addition to the averaged value. BTW: We're running the LMV761 from a 5V supply rail.

    Q. What would be your proposed test setup to measure the hi-Z state?

    Regards,
    dB
  • 0 in reply to dB
    TI__Intellectual 1740 points
    dB,

    I would recommend using a 1k pull up resistor to supply and a 1k pull down resistor to GND at the comparator output. This will make the output at mid supply when the output is in a hi-Z state after shutdown. You can measure the timing from the point at which shutdown is enabled to the point at which the output reaches mid supply.

    Regards,
    Jaskaran
  • 0 in reply to Jaskaran Atwal
    Prodigy 60 points

    Hi Jaskaran,

    Thanks for the recommendation. Is Ti proceeding with the measurements? It would be good to have the figures at high-temp, too.

    FYI: This post ( )requests a Tina spice model that includes the shutdown pin: 

    It is marked "resolved", but the LMV761 model is still dated 2012!


    Regards

    dB

  • 0 in reply to dB
    TI__Intellectual 1740 points
    Hi dB,

    The measurements were taken on 5 units running at 5V supply. Below are the results:
    Unit1: 20.6ns
    Unit2: 20.4ns
    Unit3: 19.6ns
    Unit4: 20.0 ns
    Unit5: 19.2 ns
    I see that the model was not updated and unfortunately we are not able to add this feature now. I have however noted this for our future parts to include the shutdown feature in the model and also possibly include the time from shutdown to output going into the high impedance state in the datasheet.

    Regards,
    Jaskaran
  • 0 in reply to Jaskaran Atwal
    Prodigy 60 points

    Hi Jaskaran,

    Thanks very much for the measurements.

    That helps us address a tricky implementation issue.

    Regards

    dB