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TXB0104 / Behavior at higher input voltage than VCCI

Hi,

Please let me ask about behavior at higher input voltage than VCCI.

I know that the recommended max VIH for data inputs is VCCI, but I think it should not damage to device if the higher input voltage that VCCI will be input unless not over abs max voltage. Is my understanding correct?

And also I'd like to know the behavior of output signal when the higher input voltage that VCCI will be input.

Best Regards,

Sonoki / Japan Disty

  • Hi,

    I also check the simplified block diagram in Fig 5. At this time, the customer plan to use with VCCA=1.8V and VCCB=3.3V, and now they are asking the behavior at 2V input to A input pins. Is there no possibility of leak current from A input to VCCA when 2V input to A with VCCA=1.8V?

    Best Regards,

    Sonoki

  • Satoshi - My feedback is below:

    Satoshi Sonoki said:

    I know that the recommended max VIH for data inputs is VCCI, but I think it should not damage to device if the higher input voltage that VCCI will be input unless not over abs max voltage. Is my understanding correct?

    That is correct. Exceeding the Absolute Maximum Ratings could produce permanent device damage.

    Satoshi Sonoki said:

    And also I'd like to know the behavior of output signal when the higher input voltage that VCCI will be input.

    I will try to investigate in our lab. This will take me a few days to get to.

    Best Regards,
    Nirav

  • Satoshi Sonoki said:

    I also check the simplified block diagram in Fig 5. At this time, the customer plan to use with VCCA=1.8V and VCCB=3.3V, and now they are asking the behavior at 2V input to A input pins. Is there no possibility of leak current from A input to VCCA when 2V input to A with VCCA=1.8V?

    I will also check this in the lab as well. Thanks.

    Best Regards,
    Nirav

  • Hi Nirav,

    Thank you for your support. I'm waiting for the result in your rab.

    Best Regards,
    Sonoki
  • Hi Nirav,

    Do you have any update?

    Best Regards,
    Sonoki
  • Satoshi,

    Sorry for the late reply. This request got buried with the other e2e tickets. I will try to look at this tommorow. Thanks.

    Best Regards,
    Nirav
  • Satoshi,

    Satoshi Sonoki said:

    I also check the simplified block diagram in Fig 5. At this time, the customer plan to use with VCCA=1.8V and VCCB=3.3V, and now they are asking the behavior at 2V input to A input pins. Is there no possibility of leak current from A input to VCCA when 2V input to A with VCCA=1.8V?

    The lab data is shown in the table below. There is leakage from the I/O to VCC if the I/O voltage > VCC voltage. The leakage is more proportional to (a) I/O voltage, and (b) # of I/Os with an applied voltage > VCC.

    Please check back with the customer to see if this is acceptable and let me know. Thanks.

    Best Regards,
    Nirav

  • Hi Nirav,

    Thank you for providing lab data. It's very helpful to know the behavior at I/O voltage > VCC condition. There is actually leakage but I understand that it will not damage to I/O pins. Then now I'd like to know if there is possibility of unexpected behavior at I/O voltage > VCC condition, like output inverting or something.

    Can you ask your designer about it?

    Best Regards,
    Sonoki
  • Sonoki,

    Our design resources are prioritized on other tasks. You would need to provide us with revenue opportunity for this device to prioritize our design resources to support this request.

    Best Regards,
    Nirav

  • Hi Nirav,

    Sure. Let me close this thread. Let me ask again with revenue opportunity if I need your further support.

    Best Regards,
    Sonoki