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SN74AHC1G14: Looking for hysteresis values @ VCC=3.3V

Felix Risch25
Intellectual 1110 points
Part Number: SN74AHC1G14

Hello team,

one of my customers is looking for the hysteresis values Vt+ and Vt- for a supply voltage of 3.3V. Can you provide us the values for that?

Thank you very much and kind regards,

Felix

  • 0
    TI__Guru* 97046 points
    Hello Felix,
    The values are provided in the datasheet in the '3V' rows. Since most 3.3V supplies are not perfect and can have significant variance, we give the worst case scenario values here, which are what should be used for a new design.
  • 0
    TI__Guru* 97046 points
    *****
    The primary concern is to ensure that a high is detected, if the supply ranges between 3.3V, 3.3+5% (3.465V). We did a linearization and an interpolated 2nd order function on Excel:

    VCC=3.3V --> VT+,max = 2.38V/2.387V
    VCC=3.465V --> VT+,max = 2.482V/2.495V

    In general, they need a confirmation from TI that the values are allowed to be interpolated and derived from which point or a relevant enable the hysteresis values for VCC=3.3V or 3.465V.

    Can we provide them a value, where we can guarantee that the logical High is detected, or at least with low probability on failure?
    *****

    Using linear interpolation will result in values that are safe assumptions - ie we can guarantee operation within these values. You should use only the 3V and 4.5V values to get these results:

    At 3.3V, VT+, max = 2.39V
    At 3.465V, VT+, max = 2.4945V