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.

TPS2493: Current limit threshold for power-limited does not match Application Design Example

Part Number: TPS2493

Tool/software:

Hi,

We use Power-limiting mode

The datasheet on page 3 states that the current limit threshold voltage with "power limiting trip" is 25mV

However the Application Design Example on page 20-24 uses 50mV for the calculation of Rsense despite being power-limited:



Additionally, the datasheet is not very clear on how to choose between Power-limiting and Current-limiting modes I was able to infer some of the logic from the datasheet lines below, but a more explicit explanation would be appreciated.

and


Could you please clarify:

  1. What value (25 mV or 50 mV) should be used for current limit threshold in power-limiting mode?

  2. How to definitively determine whether the design is operating in power-limiting or current-limiting mode?

  • Thanks for reaching out.

    Current limit threshold V(VCC-SENSE) with power limiting trip means that the device is in power limit. Please see the test condition, VDS = 48V in one case and 18V in another case. When the device is in power limit condition, the current flowing through the RSNS will 25mV/RSNS.

    Current limit threshold V(VCC-SENSE) without power limiting trip means that the device is in current limit. Please see the test condition, VDS = 0V. When the device is in current limit condition, the current flowing through the RSNS will 50mV/RSNS.

    Green Circle: Current Limit

    Blue Circle: Power limit