UCC39002: Rsense requirement/purpose

Ann_Lien

Part Number: UCC39002

Hello expert,

May we know what is the purpose Rsense inside the module? Customer used the calculator and found out if they changed Rsense to zero and error will show. Thanks a lot!

Best regards,

Ann Lien

over 4 years ago

0 David Huang33 over 4 years ago

TI__Genius 9140 points

Hi Ann,

the Rsense is placed in series with resistor divider on output voltage sampling of the module.

if customer do not know the resistor, you can set a resistor as big as possible.

0 Ann_Lien over 4 years ago in reply to David Huang33

TI__Genius 14830 points

Hello David,

Thanks for your reply! May we know what is the suggest resistor for as big as possible? Thanks a lot!!

Best regards,

Ann Lien

0 David Huang33 over 4 years ago in reply to Ann_Lien

TI__Genius 9140 points

Hi Ann,

since The Rsense is in parallel with Radj in the system, a bigger Rsense will have less influence on Radj calculation.

usually I would use Mohm resistor for Rsense calculation.

and if you use a small value of Rsense, please make sure you add the correct Rsense in the calculator.

you can refer to below setting up the load share controller and Rsense/Radj.

Power management

Power management forum

UCC39002: Rsense requirement/purpose