LM5121: boost not work

Hi,

We have change Rcomp to 7.68k.

thanks!

Jeff

Hello Jeff,

On the schematic, it seems M2 is not connected. Is this correct?

Best regards,
Brigitte

Hi Brigitte,H

sorry, this is not final schematic.

I have pass to you in private message.

thanks!

Jeff

Hi Brigitte,

And I have a question about Zero cross detection function?

What is this for?

I can't find more detail in datasheet.

Thanks!

Jeff

Hi Jeff,

Could you check the IC Pin17 VCC, if no VCC may be the IC is damage.

Hi Dehuan,

VCC about ~7.65V. thanks!

Hi 

The chip has a normal VCC voltage. and the UVLO pin voltage is more than 1.2V， the IC should be work If the all parts value are correct.

From the schematic, it should be work. 
Could you check whether the parts on the PCB board are correct？

Hi Dehuan,

Would you please add me to friend?

I need pass final schematic to you,

I have found many component value is different with webench suggestion.

If possible, need you help to check the value again.

Thanks!

Jeff