TPS62130: inductor open/short

Abraham Choucair

Intellectual 530 points

Part Number: TPS62130

What is the effect on the IC and output of the step down converter . if inductor is shorted or open

over 8 years ago

0 Chris Glaser over 8 years ago

TI__Guru**** 150930 points

Are you doing an FMEA?

If the inductor is open (not present), Vout will be high impedance and the IC will likely turn on the high side FET at 100% duty cycle to try and get the output voltage up.

If the inductor is shorted, then Vout will be shorted to SW. When the high side turns on, Vin will appear at Vout. This will likely damage the load and IC.

In the future, please add some more words to the title of your post.

0 Abraham Choucair over 8 years ago in reply to Chris Glaser

Intellectual 530 points

Yes, I am doing FMEA

0 Abraham Choucair over 8 years ago in reply to Chris Glaser

Intellectual 530 points

Hello Chris, what do you mean to get the output up. ?
Inductor is opened. NO connection to the output

0 Chris Glaser over 8 years ago in reply to Abraham Choucair

TI__Guru**** 150930 points

Yes, that's correct. There is no connection from SW to Vout.

But the voltage divider to the FB pin is still connected to Vout. Since Vout will be at 0V, FB will be at 0V. Since this is below 0.8V, the high side FET will turn on. The IC is trying (but unable to) get Vout up to the setpoint.

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TPS62130: inductor open/short