TPS25921

Mehul Mistry

Hi,

I am using the TPS25921 efuse for my design . Css =1nF R1 = 680k R2=33k R3=68k Rilim=100k. A DC DC boost converter is connected at the output. This circuit works satisfactorily with the load without any problems.

But when I add a schotky diode in series with the input for reverse voltage protection, the circuit fails and the TPS25921 gets damaged (pulls excessive current from input or gives a constant output of 6V for all inputs >10V ).

What would could be causing the problem ? Why is using a schotky diode for input protection causing such a failure?

Regards,

over 9 years ago

0 Dinesh Kumar6 over 9 years ago

TI__Intellectual 2980 points

Hello MM,
This is strange, could you please send us your detailed circuit with all parts values including Cin and Cout and the series schottky diode . will solve this problem.

Regards
Dinesh

0 Mehul Mistry over 9 years ago in reply to Dinesh Kumar6

Prodigy 20 points

Hi,

Cin is around 4.7uF and Cout is 1 uF . The output goes to a boost converter which draws a peak pulse current of around 0.25A and the average current is around 0.15A. The diode used was 1N5820 .

Currently , I have used an NMOS in the ground path for reverse battery protection . It seems to be working fine with it.

Regards
MM

0 Dinesh Kumar6 over 9 years ago in reply to Mehul Mistry

TI__Intellectual 2980 points

Thanks MM,

Good to know that this is problem is solved and your design is working perfectly.

Regards
Dinesh

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TPS25921