UCC2818A: Ferrite beads on GATE of FET

ACGUY

Guru 11170 points

Part Number: UCC2818A

Hello E2E,

Is it possible to damage the DRVOUT if ferrite beads are installed on the FET gate?

Regards,
ACGUY

over 3 years ago

0 Mike O' over 3 years ago

TI__Guru* 75805 points

Hello Wenbin,

Can you take a look at this for us?

Regards,

0 David Huang33 over 3 years ago in reply to Mike O'

TI__Genius 9140 points

Hi ACGUY,

adding ferrite bead on the mosfet Gate pin is commonly used to help reduce the ringing on the VGS. It should also help on the DRVOUT on the controller side.

Please make sure the voltage on the DRVOUT do not over the controller's spec requirement. The controller can be safe if all the voltage on the controller can meet the datasheet requirement.

hope this helps you.

0 ACGUY over 3 years ago in reply to David Huang33

Guru 11170 points

Hi David,

Thank you for reply.
I understood about ferrite on Gate by your comment.
Our customer changed the FET for PFC from R6025ANZ(Rohm) to R6050JNZ(rohm), many UCC2818A were damaged.
The damaged devices has near short between DRVOUT and GND.
I don't think there is a quality issue with the device, but I haven't been able to determine the cause.
Can you guess the cause of this event?

Regards,
ACGUY

+1 David Huang33 over 3 years ago in reply to ACGUY

TI__Genius 9140 points

Hi ACHUY,

I guess over votlage stress on the DROUT pin let the controller fail.

Please check the votlage especially at transient /start up/ ocp condition to see whether the votlage already over spec.

you can also try to increase the turn on/off resistor to lower the influece from mosfet to controller to see whether any improvement.

0 ACGUY over 3 years ago in reply to David Huang33

Guru 11170 points

OK, I'll confirm it.

Thx,
ACGUY

0 David Huang33 over 3 years ago in reply to ACGUY

TI__Genius 9140 points

ok, please allow me to close the post.

Power management

Power management forum

UCC2818A: Ferrite beads on GATE of FET