• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 63 subscribers
  • Views 473 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

TPS74401: Clarification of Max. Rating and Recommended Condition

TPS56C230: Clarification of Max. Rating and Recommended Condition

Ella KIM
Expert 4212 points
Part Number: TPS56C230
Other Parts Discussed in Thread: STRIKE, TPS74401

Hi team,

Please find the related thread. I believe TPS56C230 has internal ESD diode as well, but Max. rating and Recommended operating condition indicate the same value for EN pin. Could you help me to clarify it?

Thanks,

  • +1
    TI__Guru 56985 points

     

    The TPS56C230 EN pin lists an absolute maximum voltage of - 0.3V to 6V and a recommended operating range of -0.3V to 5.5V.

    We recommend that the EN pin operate between - 0.3V and 5.5V and voltages greater than 6V on the pin could cause internal damage to the device.

    And yes, the EN pin has internal ESD protection to protect the pin from very high dV/dt, high voltage, low-energy discharges.  Under a Human Body Model, the TPS56C230 is rated to withstand +/- 2000V, but the pin itself will not reach 2000V.  The Human body model is a 100pF capacitor charged to 2000V discharging into the pin through a 1500Ω resistor, so the pin will be clamped, and discharge the 200μJ of energy through the 1500Ω resistor.

    Note: During an ESD strike the clamping voltage will be greater than 6V.  TI does not guarantee the clamp voltage during an ESD strike or for any sourced current, though the 6.0V DC will not enable the ESD protection clamp.

  • 0 in reply to Peter James Miller
    TI__Expert 4212 points

    Peter,

    Thank you for the explanation and I'd like to ask more specifics.

    1. How does the device operate when the voltage of 5.5~6V is applied to V_EN? If customer uses 5.5V for EN pin HIGH, which is in normal operating condition, there will be inevitably an overshoot voltage between 5.5~6V. Can Customer still see this as operating in a normal condition?

    2. When it come to Vmin spec of EN pin, TPS74401 has internal ESD diode with 0.3V of forward voltage. And that's why Abs. rating is indicating -0.3V for Vmin spec of EN pin, while the recommended operating condition is indicating 0V for Vmin spec of EN pin with some buffer than Abs. rating. (Please find the answer from Stephen in the related question)

    I guess the same can go for TPS56C230 but both spec of TPS56C230 is specified same as -0.3V. Is it just that different business units have different ways of stipulating?

  • 0 in reply to Ella KIM
    TI__Expert 7500 points

    Hi Ella,

    Please let me check and feedback to you on Monday.

    Thanks,

    Lishuang

  • +1 in reply to Ella KIM
    TI__Guru 56985 points

     

    1) The Device is guaranteed to operate within the datasheet listed specifications for the recommended operating range, and not sustain damage upto the absolute maximum range.  For example, the leakage current on the EN pin might be higher between 5.5V and 6V, but pulling the EN pin to 6V would not damage the TPS56C280.  Pulling the enable pin between 5.5V and 6.0V is not going to cause the device to shut-down or operate abnormally 

    2) Yes, this is just different product lines and different ways of specifying the device.  In some cases, the parametric performance can be specified upto the maximum safe operating level, in some cases, additional margin is left between the specified range and the safe range.

    Note:  A - 0.3V absolute maximum rating on a pin does not mean that the ESD diodes will clamp the voltage at - 0.3V, it means that the ESD diodes wont clamp the pin voltage at any voltage greater than or equal to -0.3V, the actual clamp voltage will vary with process parameters.