• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 1062 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TPS3700-Q1 Design Procedure

Toshio Ushikubo
Mastermind 9620 points

Hello,

Please answer following question from customer.

 

Please answer if I can use Vit- instead of (Vit+ - Vhys) for figure (4).

I think Vit-=(Vit+ - Vhys) and minimum and maximum value of Vhys is not specified so it is better to use Vit-.

 


 

Best Regards.

 

  • 0
    TI__Guru 60112 points
    Ushikubo-san,

    This thread has been moved to the Supervisor and Reset IC forum for more appropriate support.

    Regards,
  • 0 in reply to Eric Hackett
    TI__Guru 55940 points
    Thanks Eric.

    Ushikubo-san,

    You may use Vit- if that works better for your application. The calculations are meant as an example to meet the example design requirements. By using Vit-, you are simply designing your application so that the Vit- threshold is the more accurate threshold.

    Very Respectfully,
    Ryan
  • 0 in reply to Ryan Eslinger
    TI__Mastermind 43610 points
    HI Ushikubo-san,

    To clarify Ryan-san's explanation; the device is trimmed for Under-Voltage as a falling threshold (meaning falling out of the valid voltage window). So you can use Vit+ with a little less accuracy in the threshold that if you used Vit-.

    Regards,
  • 0 in reply to JCHK
    Mastermind 9620 points

    Hello Ryan-san and John-san,

    Thank you for your answer.

    I can’t understand why equation (4) uses “Vit+ - Vhys” instead of Vit- for Figure 20. Typical Application.

    I believe “Vit+ - Vhys = Vit-”, so using Vit- in the equation is easy to understand.

    Could you please advise the reason why equation (4) is using “Vit+ - Vhys”?

    Best Regards.

  • 0 in reply to Toshio Ushikubo
    TI__Guru 55940 points
    Ushikubo-san,

    As both Vit+ and Vit- are specified min/max in the Electrical Characteristics table you may use either. In this design example Vit+ was used. It is an example only, if you would rather use Vit- you may.

    Very Respectfully,
    Ryan