• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 39 subscribers
  • Views 366 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.

WEBENCH® Tools/TPS7A7300: WEBENCH® Tools/TPS7A7300

Dalton Vono
Prodigy 70 points
Part Number: TPS7A7300
Other Parts Discussed in Thread: LM1085, TLV62585

Tool/software: WEBENCH® Design Tools

Hi all!!

I'm trying design a regulator using the TPS7A7300 and I'm having problems in WEBENCH. The input voltage is 5V (USB), Vout is 3.7V and Iout max is 2.5A. When I enter this values in WEBENCH the result is an error, "Junction temperature is too high". I tried use the values showed in datasheet (Vin = 1.425 to 6V, Vout=1.25V and Iout=3A) and WEBENCH result an error too. Are there bugs in WEENCH or in TPS7A7300 model?

  • 0
    Prodigy 70 points
    One more detail. I'm following a reference design of a GSM module that uses the same regulator in its Evaluation Board, and, of course, it works. But, in my board, it doesn't.
  • 0 in reply to Dalton Vono
    TI__Intellectual 2320 points

    Hi Dalton,

    We are looking into your query. We will soon get back to you.

    Thanks & Regards,

    Harish

  • 0 in reply to Harish K R
    TI__Intellectual 2320 points

    Hi Dalton,

    Apologies for the delay.

    1. For input voltage of 5V (USB), Vout = 3.7V and Iout max is 2.5A, TPS7A7300 will hit maximum Junction temperature supported by the device.

    Below are the details.

    LDO power dissipation (Pldo)  = (Vin – Vout) * Iout = 3.25W

    Junction Temperature (TJ) = (Pldo * RθJA) + TA = 146.025degC which is exceeding device maximum range of 125degC

    where RθJA is Junction-to-ambient thermal resistance of the package = 35.7degC/W

    and TA is ambient temperature = 30degC

    Instead you can either use LM1085 (LDO) or TLV62585 (Switching Regulator if you need higher efficiency)

    2. Vin = 1.425 to 6V, Vout=1.25V and Iout=3A will also fail for this device due to same reason mentioned in point 1 for Vin = 6V.

    Hope this answers your query. Kindly feel free to get back to us in case you need any help.

    Thanks & Regards,

    Harish