LM5170-Q1: LM5170, Why not Boost to 86v

Hi Wenwu,

I am a bit confused about your description. Do you mean LM5170 works well at buck mode (80V -> 60V), but LM5170 does not work at boost mode(5~12V ->80V)?

Best Regards,

Feng Ji

Yes , if there is any suggestion for the issue?

Hi Wenwu,

I would suggest to have some waveforms to have a better view. Maybe you can probe Vin, Vout, Vsw, SS.

Are you using the circuit breaker function?

Best Regards,

Feng Ji

We did not use he  breaker function,and will provide the  screenshoot to view.

WE checked the 12v and 6v wave of LO/SW  , the 6V sw wave is not squre wave.

Now The LM5170 can boost work from 6v  to 86v , But only can provide 0.3mA current of 6v in the states, We need provide big current as set 20A when the LV side voltage is 6v . Please help to analyse  this issue.

Hello Wenwu,

Thanks for the additional information.

We will have a look at it after the weekend.

Best regards,

Harry

Hi Wenwu,

What happened if you draw more than 0.3mA?

Best Regards,

Feng Ji