LM5050-1: Disabling LM5050 reverse current protection

Jean Ricard

Part Number: LM5050-1
Other Parts Discussed in Thread: LM74500-Q1

Hi guys,

our system is directly connected to a battery and we want to protect against polarity reversal, but our system is bidirectionnal. We want to be

able to regen a certain amount of current back to the battery. Would it be possible to connect the LM5050 this way to benefit from polarity reversal protection and avoiding the reverse Vsd cutoff?

(we already have this circuit)

There is possibily a missing polarisation though,

Maybe a scheme like this would be more appropriate:

Any thoughts?

over 3 years ago

0 Praveen GD over 3 years ago

TI__Guru 57737 points

Hi Jean,

Please have a look at LM74500-Q1 which has only Reverse Polarity Protection but does not have reverse current blocking functionality.

This device is suitable for your application.

0 Jean Ricard over 3 years ago in reply to Praveen GD

Prodigy 30 points

Hi Praveen,

thanks for the suggestion, but we need the 75V tolerance of the LM5050.

Is a serie diode could be another option or another solution as the ones above?

0 Praveen GD over 3 years ago in reply to Jean Ricard

TI__Guru 57737 points

Hi Jean,

You can consider using a circuit like shown below. With this configuration, the OUT is always diode drop less than IN and hence the FET will always be ON and does not block reverse current.

Power management

Power management forum

LM5050-1: Disabling LM5050 reverse current protection