I have a SOT-23 SMD transistor marked "2.X L" as shown in the image. enter image description here

I managed to find out that "2X" stands for 2N4401 and the dot seems to mean "lead free". But I couldn't find the meaning of the perpendicular "L". I think it could be a "date code" but I'm not sure and I don't know either what its purpose is (e.g. does it affect the pinout?). I would appreciate any help.



1 Answer 1


It is a date/manufacturing code. Does not change pinout in any way.

Look at this datasheet:https://www.mouser.com/ds/2/308/MMBT4401LT1-D-108598.pdf

Marking diagram


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