LM5066I: Output Hotswap application -- to protect MOSFET and Hotswap IC.

Sorry, word typo. is hot plug not hot swap.

Hi Kunal,

I mean the the output, the output of our design are connector with cables. Output connector have 54V and hot plug in the another board, On the output side, how to do to protect it?

Other board has how much input cap and load current?

About 2000uF and 3~4A.

Please share filled design calculator for review.

LM5066 Design_Calculator_REV_B_PA-W2T-A.XLSXLM5066i Design Calculator with FET Recommendation_PA-W2T-A.xlsm

Hi Kunal,

I do both of LM5066 and LM5066I calculator.

Let me check. 

Are we seeing FET and LM5066i failing?

Not yet, but I need to do something for preventing FET and LM5066i failed when 54V output to hot plug in board.  

Let me get back on this.

Sorry, please explain on "Are we seeing FET and LM5066i failing?" you mean. I think that you mean FET and LM5066i are already damaged, right? 

If yes, the LM5066i is our first design and will happen on 54V output to hot plug. I request you to provide how to  design robust way to protect FET and LM5066i damaged. Or do you review our schematic is fine?

I will review schematic and get back.

Hi Rakesh,

Thanks for your response. However, if our application has hot plug into another board on +54V_OUT(Source of FET), can we place 2*TVS instead of schottky diode on output? 

Hi Kunal,

Thanks for your response. For safty design, it is better to add 2 more TVS and still keep schottky at output, right?