• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 385 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.

LM5060: reverse protection

Betty Guo
Expert 7300 points
Part Number: LM5060
Other Parts Discussed in Thread: LM74800-Q1, LM74700-Q1,

Hi team,

below is customer schematic, for * is not added. they have a reverse protection issue.

add 5V on OUT pin of LM5060, found the voltage of R167 is 2.4V and the Vs voltage of Q13&Q12 is 2.45V. it seems the FET is turn on, the reverse protection is not work.

could you help to check it .

power1.pdf

  • 0
    TI__Guru** 105361 points

    Hi Betty,

    Thanks for reaching out!

    This circuit provides reverse polarity protection at the input when GND is fed +ve with respect to VBAT_IN. i.e., VBAT_IN is connected to the ground. 

    When powered from Vout, there are paths from OUT to GATE, which could partially turn-on the Q13. Is it a concern ?

    From where the 5V comes in the system ? Can you share the use case details 

    Best Regards, Rakesh

  • 0 in reply to Rakesh
    TI__Expert 7300 points

    Hi Rakesh,

    yes, you are right.

    customer need LM5060 can turn off the FET when 5V power placed on Vout. It seems they need LM5060 achieve back chananel(Vout to VIN) protection instead of reverse.

  • 0 in reply to Betty Guo
    TI__Guru** 105361 points

    Hi Betty,

    Ideal diode controller LM74700-Q1, LM74800-Q1 would be the right devices to support reverse current blocking.

    LM5060-Q1 provides input side protections (OVP, UVLO, slow OCP, input reverse polarity) but not active reverse current blocking. 

    Best Regards, Rakesh