Help me identify this component "A91Cd"

[Armadillo]

Was repairing Antec 750W and came across this component marking "A91Cd" that I have never seen before.
Wonder what device is that.
Thanks;

[4thDoctorWhoFan]

I believe that a A91 translates to a BAS17.
If you google BAS17, you should easily find a datasheet.   It's basically a diode between two of the pins.

[cvanc]

One of the solder joints on that thing looks highly suspicious, FYI...

[Armadillo]

Thank you both for reply;

@4thDoctorWhoFan - Thanks, but I really don't think is a low voltage stabistor. I don't think this device would be used in PC power supply, would it? I don't know really. It near the LED side of the opto-isolator EL816, all 3 legs are used, hence I am inclined to think is the TL431 variants, not sure,. guessing.

@cvanc - Thanks for reply. Just checked and confirmed, its the lighting & shadow effect. Visually checked and continuity checked [pin and solder/track]

[amyk]

That would be an AP431AR.