• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 369 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.

TPS24711: power liimit formula

Given Ding
Genius 10205 points
Part Number: TPS24711

Hi Team, 

Here are two questions regarding TPS24711. 

1. how to get the equation 1 in datasheet? what does 3125 means? 

2. In function block, there is a block, could you please kindly help explain the details on the block?

For example, what does Kpa means, what does B mean? why does it output min value of [Kpa/B, 675mV]? Thanks. 

BRs

Given 

  • 0
    TI__Mastermind 39820 points

    Hi Given,

     

    Thanks for reaching out to us.

    Equation 1 is an empirical formula based on the internal design of the device to find the relation between RPROG and required PLIM to specify. We can’t share that information. However, please let us know why would the customer like to know this information. Equation 1 is sufficient to find out RPROG corresponding to desired power limit of PLIM.

     

    This block represents the power limit engine, which determines the maximum current allowed through the MOSFET (ILIM).

    ILIM,CL is the programmed current limit, PLIM is the programmed power limit, and VDS is the drain to source voltage across the Hot Swap MOSFET. 675mV is the voltage across RIMON at which current limit kicks in. Hence, 675mV equivalents to ILIM,CL.

    It’s indicated in the functional block diagram that the ratio of RIMON to RSET is 27. B is VDS. Kp*A  equivalents to PLIM . 

  • 0 in reply to Avishek Pal
    TI__Genius 10205 points

    Hi Avishek, 

    Thanks for your reply. 

    #1 customer just want to make it clear on the formula and guide their design. 

    #2. then what does the symbol " ¬ " means? 

  • 0 in reply to Given Ding
    TI__Mastermind 39820 points

    Hi Given, 

    Customer can follow the Equation 1 to calculate the the value of RPROG corresponding to the desired PLIM. This symbol " ¬ " means the minimum between ILIM,CL and (PLIM/VDS). This symbol is similar to the below indicated curve.