Grateful for Help ID A Regulator(?)

Semiconductor Discrete Semiconductor Products
,
1

I have a surface mount part here that is an SOT-89-3.
I believe it to be a Voltage Regulator from a company called RichTek. But, I don’t know.

The only Makings on it are a JE and a 31.

Can anyone help me ID this chip?

I most appreciate your help!

Best,
-Richard Galambos

2

Hello Richard,

Welcome to the DigiKey Technical Forum. I tried to do a search for any part marking information for RichTek. I did not have any success. This generally means this is not public information. I could not find any information for the marking code you have.

3

Thank you for trying. I am grateful to you.

I have an atlas DCA Pro (DCA75).

When I connect this to the component, I get:

Thyristor (SCR) →
Pin 1 - Gate
Pin 2 - Anode
Pin 3 - Kathode

However, I have trouble believing this to be true.
The component in question is possibly causing the fault in the circuit I am repairing.
So, it may be damage - then, it may be an SCR. Again, though, and SCR in this situation seems unlikely.

Thanks for trying!
Best,
-Richard Galambos

4

Hi Richard,

Wonder, do you have a chance to paste here a photo of the device and what is important,
a photo of the PCB, showing the components around it?

Sometimes a thyristor is used as a crowbar protection.

Heke

5

I think you are correct. I have purchased a new SCR and the circuit will work briefly and die again.
Crowbar is likely.

Thank you for your help.