TPS24700: Need to prevent reverse current flow

Dan Closson

Part Number: TPS24700
Other Parts Discussed in Thread: TPS24740

Hi TI community,

I'm working on a project with dual load switch requirement and am looking at using the TPS24700 to limit inrush and prevent damage from hot-swapping. One requirement for our application is to not allow current flow in the reverse direction. I've considered a diode but would prefer a back-to-back mosfet load switch structure to prevent voltage drop and reduce power dissipation. Any reason why I cannot use 2 n-channel mosfets instead of one with the TPS24700? Any special considerations that I should be aware of.

Thanks,

Dan C.

over 5 years ago

0 Praveen GD over 5 years ago

TI__Guru 57737 points

Hi Dan,

Yes, you can use the Gate signal to drive a combination of back to back FET's. This approach will block only reverse current when the controller is disabled or the when the FET's are in turned OFF condition. This is because the controller does not have any intelligence to detect the reverse current and block the reverse current by turning OFF the FET's.

If you want true reverse blocking, please consider using TPS24740 family of Hotswap controllers.

http://www.ti.com/lit/ds/symlink/tps24740.pdf

Power management

Power management forum

TPS24700: Need to prevent reverse current flow