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TPD4E05U06: Clamping Voltage

Part Number: TPD4E05U06
Other Parts Discussed in Thread: STRIKE

Hello,

I have a question regarding the clamping voltage of TPD4E05U06 which is rated for USB 3.0. In the datasheet on page 7, it is stated that the "Clamp Voltage" is rated as max. 14V. I would like to use TPD4E05U06 for the protection of CC- and D-lines on USB-C together with MAX77751 which has an absolute maximum rating of 6V for these lines.

  • does "clamp voltage" mean that during ESD the maximum peak current will be "clamped"/limited to max. 14V? 
  • if so, will it potentially destroy MAX77751 because the CC and D lines are rated for a maximum of 6V?
  • if so, do I have to find a part that has a max clamping voltage of less than 6V? This will be quite hard with such a narrow working span between reverse standoff voltage at 5-5.5V and clamping voltage at less than 6V.
  • Or will my circuit survive because the peak voltage is too short and the ESD doesn't have enough energy? 

Kind Regards,

Den

  • Hi Den,

    does "clamp voltage" mean that during ESD the maximum peak current will be "clamped"/limited to max. 14V? 

    The clamping voltage is the voltage that will be presented to the protected IC. The clamping voltage specs here are typical values taken from the TLP curve. The TLP is useful because it has similar characteristics to an IEC 61000-4-2 ESD strike. As a result, you can correlate TLP current with IEC ESD. Below is an example from another device. 

      

    • A 2kV IEC strike = 4A TLP.
    • A 4kV IEC strike = 8A TLP.
    • A 6kV IEC strike = 12A TLP.
    • A 8kV IEC strike = 16A TLP.
    if so, will it potentially destroy MAX77751 because the CC and D lines are rated for a maximum of 6V?

    The Abs Max rating of 6V for the MAX77751 is a DC rating while the clamping voltage is a transient spec. ESD pulses are transient events that last in the nS-uS range. 

    if so, do I have to find a part that has a max clamping voltage of less than 6V? This will be quite hard with such a narrow working span between reverse standoff voltage at 5-5.5V and clamping voltage at less than 6V.

    Keeping the clamping voltage below the DC abs max rating won't be necessary and as you mentioned would be very hard to find. Most IC's don't have abs max transient specs so you would need to conduct bench testing to gaurantee the MAX77751 will survive. 

    Or will my circuit survive because the peak voltage is too short and the ESD doesn't have enough energy? 

    It is possible for the IC to survive since the peak voltage is short however you would need to conduct bench testing to confirm. 

    I would suggest looking through our ESD Fundamentals Training for more in depth details, it has a section specifically on clamping voltage. 

    Regards,

    Sebastian