TPS51120: MOSFET ISSUE

Dheeraj yadav

Part Number: TPS51120

I am using BSO150N03MDG Mosfet instead of IRF7821.

When we will on the supply due to mosfet power supply is sorted, after off the supply and remove the mosfet from pcb, power supply is not longer shorted.

Also the resistor at the gate mosfet also got damaged.

After removing mosfet at pgood we got 5 and 3.3 volt respectively too.

over 4 years ago

0 Yuchang Zhang over 4 years ago

TI__Mastermind 18510 points

Confirm with you several questions first.

1, no issue happen with IRF7821, only happen with BSO150N03MDG, right?

2, High-side or low-side mos Damage or both are Damage?

3, what’s the loading when the damage happen?

4, I quick compare the spec of both MOSFET, most are similar, just the Qrr has a little big difference. Did you do compare about the overshoot and undershoot of switching node with these two mosfet?

Yuchang

0 Dheeraj yadav over 4 years ago in reply to Yuchang Zhang

Intellectual 590 points

Currently we have only BSO150N03MDG, didn't try with IRF7821.

Mosfet was not damaged just power supply shown shorted when we connect mosfet on pcb and the gate resistor is damaged after off the supply.

0 Yuchang Zhang over 4 years ago in reply to Dheeraj yadav

TI__Mastermind 18510 points

As you said the short happened after you connect the mosfet, so firstly please Double check the pin connection of mosfet is right.

If the connection is right,

1, change the Rgate to 0ohm to try.

2, please try IRF7821.

If the same phenomenon happen after above tests, possibly something wrong with layout.

Yuchang

0 Yuchang Zhang over 4 years ago in reply to Yuchang Zhang

TI__Mastermind 18510 points

By the way, what do you mean about “After removing mosfet at pgood...”?

Could you please explain more about this?

Yuchang

0 Dheeraj yadav over 4 years ago in reply to Yuchang Zhang

Intellectual 590 points

I will be get back to you after checking result with IRF7821 !

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TPS51120: MOSFET ISSUE