• Resolved

ISO7141CC: Requirement of Rise/fall time of input signal

Part Number: ISO7141CC

Hello support team,

I'd like to know the maximum rise time and fall time of input signal into ISO71xx series.
But these specifications are not seen in the datasheet.
So please teach me them.

Best regards,
M. Tachibana

  • Hi Tachibana,

    Usually input signals do not have a specific rise and fall time requirement.
    The input signal is monitored based on the threshold voltage and is independent of Rise and Fall time of input signal. that is for ISO71xx when the input signal voltage is greater than 2V is consider as logic HIGH and signal voltage lower than 0.8V is considered as a logic LOW.

    Hope this answers your query,

    Regards
    Tejas
  • In reply to Tejas Hommaradi:

    Hello Tejas-san,

    For logic ICs like SN74HC00, the maximum value of Input transition rise and fall time (Δt/Δv) is specified.
    When the input voltage increase or decrease slowly, I think that will cause chattering and through-current at near the threshold voltage.

    Do the inputs of ISO71xx have hysteresis characteristics?
    Is it safe to increase or decrease the input voltage of ISO71xx slowly?

    Best regards,
    M. Tachibana

  • In reply to Masanori Tachibana:

    Hi Tachibana,

    Yes, ISO71xx have inputs have a hysteresis characteristics and wouldn't cause chattering.

    Hence it is safe to increase or decrease the input voltage of ISO71xx slowly.

    Regards

    Tejas

  • In reply to Tejas Hommaradi:

    Hi Tejas-san,

    Thanks for teaching me that information!
    I understood that.

    Best regards,
    M. Tachibana