Component Identification

[H2814D]

Hello again everyone. I am trying to identify a component on a circuit board. I do not have and cannot find the schematic to assist, but if you can give me a reasonable probability by looking at the component, that would help. They are small. 2.7mmx1.3mm. They have three legs and are on a dual voltage controller board for a power supply. There are several of the same components on the board. Most of them have 2x and then another x that looks like it is on its side, or 2T and then a sideways U.

Thanks in advance.



[Mod Note: Resized huge image]

 

[H2814D]

Well I just found my answer. A 2x on a SMD component signifies a SOT-23 NPN transistor. A 2T is a PNP transistor with the same package. Well anyway...hopefully this will help someone else.

 

[(*steve*)]

In SOT-23, 2x could mean devices including KST4401, MMBT4401, SO4401, or TMPT4401.

All are non silicon transistors rated at 60V and 600mA.

Likewise 2T, if it is a transistor is a similar variety of 40V 600mA silicon pnp transistors with the numeric part of their part number being 4403

 

[H2814D]

Thank you, *steve*. Because I had questions about SMD components, I started looking for information covering the topic. I found this link to what appears to be very useful information covering just that. I hope it is all right to post it here. If not, let me know and I will delete (if I can) the link.

http://www.sphere.bc.ca/download/smd-codebook.pdf

After taking a look at a group of components on a board I have photos of, I do notice not all of the components are listed in the document. I am not finding a bunch of them, actually. GB5, GB6, LM393, DAP8C, etc. There must be another more comprehensive resource out there somewhere.