TPS25981: Could you please help us review schematic?

Hi Sir,

Any feedback? Thanks~

3107.HOT PLUG controller design.pdfThank you Arush!

I updated my schematic again, could you please help to check it again? Thanks~

Hi Arush,

Any feedback for the latest schematic? Thanks~

Hi Arush,

Thank you for your help. I've updated schematic.

And I had two questions.
1) For U23 : If we needn't OVLO, can I also pull it to GND?

2) Control power sequence between 12V and 3.3V : Our purpose is to tallow 12V supply our board firstly then allow 3.3V to supply, so we used U23 PG pin to enable U24, can you help us to check this design to see if it can work? Thank youHOT PLUG controller design_20250912.pdf

Hi Yu Jen Wang,

Yu Jen Wang said:

And I had two questions.
1) For U23 : If we needn't OVLO, can I also pull it to GND?

Yes, if OVLO is not required, then pull the OVLO pin to GND.

Yu Jen Wang said:

2) Control power sequence between 12V and 3.3V : Our purpose is to tallow 12V supply our board firstly then allow 3.3V to supply, so we used U23 PG pin to enable U24, can you help us to check this design to see if it can work?

Yes, you can use this sequential startup using PG of 12V as EN of 3.3V. Add a pull down at EN of 3.3V so that it is not floating at any time as when 12V eFuse will be off, the PG pin won't be actively pulled low

Best Regards,
Arush

Thank you Arush!!

I updated my design. 

For U23 :

1) I pull OVLO pin to GND directly.

2) I used two resistors (R215 is 2M ohm and R229 is 249K ohm) as divider resistor at PG pin.

3) I named this signal as PG_MAIN_3V3

For U24 : The signal pin "PG_MAIN_3V3" will enable U24

Could you please help me to do final review? Thank you so much.HOT PLUG controller design_20250915.pdf

Thank you Arush.

Hi Arush,

One question :

If we did not use FLT, am I supposed to be floating or put it to GND? Current, this pin is floating.