• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 280 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.

TPS7H1101A-SP: Is a Programmable current limit greater than 3.5A possible?

Shawn Hineline
Intellectual 360 points
Part Number: TPS7H1101A-SP

To Whom it May Concern,

I have a design that draws 3.4A typical and 3.7A max, the current is supplied by the TPS7A1101A-SP. The text in the data sheet says the maximum programmable current limit is 3.5A. If we are operating at Vjn =5.5V and Vout set to 5.0V is it possible to get 3.7A out of the part reliably, assuming we don't exceed the maximum operating junction temperature?

Thanks,

Shawn

  • 0
    TI__Guru 62930 points

    Shawn,

    There is a fair amount of variability in the CSR ratio.   We are currently working on an updated datasheet to improve the CSR data per temperature range.

    The values that will be updated in the datasheet will be the following:

    -55c range: CSR min, 45000, nom 55000, max 65000

    25c range: CSR min 45000, nom 52000, max 59000

    125c range: CSR min 45000, nom 50500, max 56000

    There may be some units that can have the Rpcl set to adequately trip at 3.7A.  However, this would be a device by device tuned solution and the variability with temperature may cause additional undesired variation.

    At 125c, the range of ICL using the full range of CSR and Rpcl at minimum of 8Kohms at 125c will be 3.44A to 4.2A.

    If this answers your question, please click "This Resolved My Issue"
    Regards,
    Wade

  • 0 in reply to Wade Vonbergen
    Intellectual 360 points

    Hi Wade,

    Thanks for the updated information! If I drop the resistor to something below 8K will it still increase the output current limit? This would be just to test the rest of the system, in the next revision we will either lower the current or use 2 LDO's.

    Thanks,

    Shawn

  • 0 in reply to Shawn Hineline
    TI__Guru 62930 points

    Shawn,

    I am  not certain of the implications of using smaller resistor than 8k.   Let me check with design and get back to you.

    Regards,

    Wade

  • 0 in reply to Wade Vonbergen
    Intellectual 360 points

    Hi Wade,

    Thanks for checking, I really appreciate it!

    Sincerely,

    Shawn

  • 0 in reply to Shawn Hineline
    TI__Guru 62930 points

    I did get quick feedback from the designer.

    He indicated that this should not be an issue with a lower RPCL.  The range is based on full process corners that we effectively will never see with relatively low volume products.  

    However, I am assuming this is for a fault scenario, and not full operation at >3A. 

    Specifications are not warranted outside of recommend operating conditions.

    Regards,

    Wade

  • 0 in reply to Wade Vonbergen
    Intellectual 360 points

    Hi Wade,

    Thank you for checking into the this, I really appreciate it! This does answer my question.

    Thanks,

    Shawn