• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 63 subscribers
  • Views 148 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.

LM5164-Q1: functional safety concerns

Sherry Liang
Genius 10255 points
Part Number: LM5164-Q1
Other Parts Discussed in Thread: LM5146-Q1, LM5146

Dear team,

My customer is studying our functional safety document, and they have some questions as below,

  1. LM5164-Q1:

           If the voltage of VIN is higher than absolute maximum rating, what’s the failure mechanism? Will SW pin output 0V or equal to VIN voltage?

          ƒ According to below picture, If the SW pin is shorted to Ground, the FET inside the chipset will be breakdown, hence the SW pin voltage will be same as Vin, right?  This could be high risk for second power stage SBC… In addition, I don't understand why the internal mosfet will  be damaged. We have the current limit function, in my understanding, SW short to ground should trigger OCP, our device should be no damage.

  1. LM5146-Q1:

           If the voltage of VIN is higher than absolute maximum rating, what’s the failure mechanism? Will SW pin output 0V or equal to VIN voltage?

          ƒ If the HO pin is shorted to VIN, VOUT=VIN, does it mean the voltage after the inductance will be equal to VIN, right? I don't understand why Vout is equal to VIN under this fault. Could you please help explain?

Thanks & Best Regards,

Sherry