TPS65400: want to know the default vref value

Hi Sam ,

Thanks for your reply,Here I've changed the sw 4's Rfb2 resistor into 2.15kohm to get 9v in the default vref(0.8),here I've attached the image of oscilloscope screen that shows the ripple voltage values.what should I do to get SW4 switch maximum current.

Hi Mark,

I'm suspecting the loop is unstable. Can you post your schematic here? Just connection of COMP4 and feed back resistor on CH4 is enough.

Regards,

Sam

Hi Sam

Here I've attached the schematic of the loop,I've only changed the feedback resistor 2 (10.5kohm) to 2.15kohm.

Hi Sam,

For my project I want use TPS65400 four bucks according to following diagram.

So according to that I've changed the feedback resistors of four buck as follows

SW1,

R3=53.6k

SW2

R10=1.77k

SW3

R15=3.12k

SW4

R21=2.15k

and also I've changed R20 40k then 30k and now I set into 10.2k. 30k and 10.2k giving same results.

Basically I want what are the changes to the default TPS65400EVM have to do to get wanted voltages and current . '

thank you.

Hi Sam,

Thank you for your support,I think that can solve problem,by the way Sam there's not schematic and layout CAD files TPS65400 PMIC

I've tried to download but there's error showed that the files are not available.If you could upload them it will help to my project.

Regards,

Rangika Mark.

Hi sam,

Thank you very  much for your quick and good assistance  here is my email.

rangikamark@gmail.com

Hi Sam,

Thank you for your quick reponse and assistance here is my email. rangikamark@gmail.com