LM25143-Q1: GND issue

HI jimmy,

my customer need online review layout, i will send the project information and customer background to you. 

Hi Jimmy,

i have send the project background to you from the mail. 

could you help review the layout of LM25143-Q1, the basic condition is as follow:

single phase output 

Vin: 9-16V

Vout:3.3V

Iout max  : 30A

expert has checked the schematic:

(1) LM25143-Q1: schematic review - Power management - INTERNAL forum - Power management - INTERNAL - TI E2E support forums

in the new schematic i suggest customer change the COMP RC to below picture:

other's part pls refer the below schematic.

jmc_cx835_cdc_subboard_a00_2024.pdf

here is PCB gerber file

1145874_JMC_CX835_CDC_SUBBOARD_A00_20240527_1910.zip

Hi jimmy,

any progress about it ?

Hello Colt,

1. I would suggest having a dedicated AGND plane and having AGND connected to PGND under the controller. Currently this is the PCB layout with Pin 35 connected via to the Sig_3_Layer where AGND is. Ideally the AGND should be on the same top layer as the IC similar to what the EVM shows. This way the components don't need to return through the board through vias which has some parasitic inductance
2. 
3. It is highly suggested to have the input capacitors placed as close as possible to the high-side FET of each VOUT channel to help with local decoupling.

Regards,

Jimmy