As the title states I’m looking to find a part labeled IRFB7440. Digikey has an item close to the one that I need but the component I have seems to have a diode built onto one of the legs (bare in mind I’m learning about this as i go please). The “diode” since I don’t know what it actually is is roundThe transistor was used in an APC 1500-S UPS and 2 out of the 4 have exploded leaving me to find replacements.

EDIT: I decided to try to remove the legs of the component and happened to pull the small cylindrical piece from it’s former home. It appears to be a spacer as I would think that a diode would have components inside. Maybe something similar to what I can see when I stare at an LED. If so, what is the purpose of having a spacer sitting between the transistor and the PCB?

Is it IRFB7440PBF?
PBF in the part number is for lead-free and not shown as part of the part number in the markings.

That is the part that I was looking to replace my bad components. Yes.

That should be the correct part for you then.


Hi Chris,

The small cylindrical part may be a ferrite bead, so make sure it goes with the correct leg when replacing the Power-FET. You can re-use the original one, as the beads rarely get damaged.


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Thanks for the help!