LM5050-1: anti-reverse connection

Hello Big Bill,

Yes, LM5050-1 can be used to implement reverse polarity protection.
Refer to "www.ti.com/.../TIDA-00992" for reverse polarity protection with LM5050-1.

Regards,
Kari.

Dear Karikalan Selvaraj :

My application is different from this one. in my application, the charger output 54.6V to charge the Battery, the function is that the charger can't reverse connect the battery, if it done， the charger stop output at once.

Hello Big Bill,

For this application, two MOSFETs connected back to back are needed to block conduction when turned off.
Is this your requirmeent?

Regards,
Kari.

Dear  Karikalan Selvaraj:

      As  below simple picture show, the charger  test needs to ensure  that    the charger and the battery  are connect  in reverse  the negative and positive electrodes,  the charger should  immediately stop the output

can  you have any good Suggestions to solve this problem, Thanks, or  can i use  the LM5050-1 to  finish  this test？ (the charger output voltage is 54.6V )

   

      

      

Charge_Reverse_Protection.pdf

tidrne8.pdf

Hello Big Bill,

Circuit shown in TI Design TIDA-00992 works for reverse input polarity protection also. Though the name says reverse battery protection, it basically does reverse input polarity protection.

Typical usage diagram is attached here.

When charger terminal is connected in reverse polarity, reverse current flows from battery back into the charged. Now LM5050 detects the reverse current quickly and turns off the MOSFET when charger input terminals polarity are reversed. Body diode of the MOSFET blocks reverse current when it is turned off. But during normal opeartion when the polarity of charger is connected correctly, MOSFET is turned on with a low resistance path to charge the battery.

Let us know if you have more questions.

Regards,

Kari.

Dear Karikalan Selvaraj:

Thanks for your help, i will to do the Pcb board to test.

Dear Dear Karikalan Selvaraj:

Do I need to use back-to-back to block conduction when turned off？

Hello Big Bill,

Yes, when turned off, LM5050 can block current from battery into the charger.
But if you require to block charger charging into the battery when off , need to used back to back MOSFETs.

Please note that LM5050 can not drive the second FET (connected in opposite orientation than the one shown in the earlier block diagram).
You may have to use a PFET for low current applications or LM5060 for driving the second FET.

Regards,
Kari.