LMR16006: LMR16006

Hi,

Yes, I believe the most likely root cause is the inductance of the long cables creating ringing at the input of the device. Can you share the layout as well? Also, can you add a transient suppressor (TVS) to clamp the input voltage? This would also see if the device can behave normally if the input voltage is clamped.

Thank you,
Katelyn

I designed same circuit with LM2576HV before. And ther was no problem with 2576hv.
İt have same input voltage area. But result is different with lmr16006.

Actually, i dont think that will help to use tvs diode.
If you can send your e-mail, i can share proteus layout.

Please send the layout to k-wiggenhorn@ti.com.

Can you take a waveform during start up, and probe the VIN pin? This will help see if the voltage is overshooting?

Thank you,
Katelyn

Hello,

I want to follow up with you. I have not received an e-mail at this point. Please let me know if you have any additional questions.

Best Regards,
Katelyn

Hello Dear Katelyn,

I have added a TVS diode and remove the R1:10K . Then problem solved. But I’m not sure which one is worked. Now I can’t try each other tvs or R1 was solved the problem. Because many boards connected to each other as cascade, and can not take the risk of burn a new IC.

I think the removing R1 is the point. Because the value(10K) was low and maybe the EN input has not immunity for high transient voltages.

What is your opinions?
Vin pin and EN pin have different charachteristics due to high transient voltages?

Best regards....