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.

The maximum voltage of external pull up resistor of reset out of TPS3838L30DBV

Hi,

I would like to know the maximum voltage of  external pull up resistor of reset out of TPS3838L30DBV.

The voltage of VDD is from 1.8V to 3.3V.

Please also see attachment.

TPS3838L30DBV_pull up_voltage.docx

 

  • Hi ,

    Pulling /RESET above VDD will turn on the internal ESD structure as mentioned in note 3 under the Absolute Maximum Ratings table.  It is important to note that this is outside of the recommended operating conditions so you may experience behavior outside of Electrical Characteristics.  To be within the recommended operating conditions, /RESET should be pulled up to a maximum of Vdd + 0.3V.

    If you choose to pull-up to 5V, you will want to size the pull-up resistor to limit the current flowing back into the /RESET pin to be between 50uA and 10mA.  

    Very Respectfully,

    Ryan

  • Hi Ryan,

    Thanks for your answer!

    So, if  we control current flowing back into the /RESET pin to be between 50uA and 10mA the external pull up voltage of /RESET can be 5V even though

    the VDD is 1.8V?

  • Hi ,

    It is not recommended as this is beyond the intended use for the device. The device was designed and characterized for use withing the Recommended Operating Conditions which are stated in a table on page 3. The device may function to your satisfaction beyond the recommended operating conditions; however, per note 1 under the Absolute Maximum Ratings table, exposure to the absolute-maximum-rated conditions (beyond the operating conditions, but less than the absolute max value) may affect device reliability. The specifications in the Electrical Characteristics and the Typical Characteristics curves are meant for the recommended operating range. If you exceed the recommended operating range, you may experience performance outside of the performance indicated in the datasheet.

    Very Respectfully,
    Ryan
  • Hi Ryan,

    Okay, thank you for your answer.

    Based on the Table3, if VDD is 3.3V and external pull up voltage of \RESET is 1.8V, it is a normal operation,right?

    Thanks!

     

  • Hi ,

    Yes, this VDD of 3.3V and /RESET pulled up to 1.8V is within the recommended operating conditions.

    Very Respectfully,
    Ryan
  • Hi Ryan,

    Okay, Thank you for your answer!