LMR14206 EVM Board

Jordda

Other Parts Discussed in Thread: LMR14206

I try LMR14206 EVM board 42V 600mA. I input 39V and then found Vout is shorted with GND. Before 39V input, I check Vout is not shorted with GND. I have replaced LMR 14206. It's the same problem. Do you know why ?? Thanks!

over 11 years ago

0 Jordda over 11 years ago

Intellectual 665 points

Besides, I check CB pin is shorted with GND. I'm very sure this short is not caused by soldering. Please help to check this issue. Thanks!

0 Alex Triano over 11 years ago in reply to Jordda

TI__Genius 12621 points

Hi Jordda,

Can you verify that when you applied 39V, the EN pin is also reading high (you can check both the test point and the /SHDN pin of the device)?

Thanks,

Alex

0 Jordda over 11 years ago in reply to Alex Triano

Intellectual 665 points

Yes, EN pin is high. EN pin is connected with VIN.

0 Alex Triano over 11 years ago in reply to Jordda

TI__Genius 12621 points

Hi Jordda,

As you know, CB should also not be shorted to GND.

You mentioned Vout was not shorted to GND before you applied 39V.

So I am guessing the CB pin was also not shorted to GND before applying 39V?

What is your setup:

Do you have a load connected?

Are you using ammeters and/or voltmeters at Vout to collect measurements?

Are you using an oscilloscope to check voltages or a multimeter?

Do you know what the input current is when you power the device and Vout becomes shorted?

How did you measure that Vout is shorted when the device was enabled?

Thanks,

Alex

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LMR14206 EVM Board