TL401 928 -> TL431

[Desbo]

I am trying to replace this transistor (well, I think it’s a transistor - a small D shape one) I cannot find reference to it anywhere. Can anyone assist a noob. Thanks.

 

[kellys_eye]

Why are you replacing it? If you don't know what it is how do you know it's faulty?

Post a pic of the device and the surrounding circuit board.

 

[Desbo]

It turns out the number is TL431, which is a zener diode. The number was so tiny and hard to read I misread it. Now I have learnt all about this important device. Hope I didn’t waste anyone’s time.

 

[WHONOES]

More accurately, it is an adjustable shunt regulator.

 

[Martaine2005]

Where does the ‘D’ shape fit in?
Ah, a TO-92 package..

Martin

 

[bertus]

Hello,

As said, the TL431 does come in a TO92 housing:

For more info see the aattached datasheet.

Bertus