I have a SOT23-3 component marked \$\underline{\textrm{L}}\,\underline{\textrm{E}}\,\overline{\textrm{F}}\,\overline{\textrm{B}}\,\textrm{V}\$ as shown in the following images:

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The following schematic snapshot shows the circuitry surrounding the device of interest which is circled in red and referenced as U11:

enter image description here

I thoroughly searched both the web and a number of SMD code databases for information but I haven't been able to come up with anything.

Can you help me to identify the component?

Update: assuming that the component is a MOSFET with Pin1=Gate, Pin2=Source, Pin3=Drain, I've removed it from the PCB and done some probing by using the diode test feature of a digital multimeter (DMM) as follows:

  1. connecting the positive lead of the DMM to the Source terminal and the negative lead of the DMM to the Drain terminal showed a voltage drop of about 0.57V;
  2. connecting the negative lead of the DMM to the Source terminal (Pin2) and the positive lead of the DMM to the Drain terminal (Pin3) there is no conduction and it looks like an open circuit, that is the MOSFET is in the OFF state;
  3. charging the Gate terminal up by touching it with the positive lead of the DMM; now connecting again the leads of the DMM as in 2. results in nearly a short circuit, that is the MOSFET is in the ON state;

So the device looks like to be a N-Channel MOSFET.

  • 1
    \$\begingroup\$ do you have any clues from other components around that one ? (this mark LEFBV doesn't seem to be a reference from founder cause it is not found in databases) \$\endgroup\$
    – user201301
    May 7, 2019 at 9:46
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    \$\begingroup\$ elektrodynamik - Welcome :-) Here are the current "Component Identification Question Guidelines". As you see, those guidelines request information and photos of the board / system, and other details too, for the best chance of successful identification. Please edit your question and add as much information as possible from those guidelines. Thanks. \$\endgroup\$
    – SamGibson
    May 7, 2019 at 12:03
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    \$\begingroup\$ Very clear photos, schematic and ruler for scale! Not something you see often from new members. +1 \$\endgroup\$
    – winny
    May 20, 2019 at 8:52
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    \$\begingroup\$ Given the large area copper on pin 2 and 3 with what looks like capacitor, pull down resistor and zener diode on pin 1, I would assume MOSFET. \$\endgroup\$
    – winny
    May 20, 2019 at 8:54
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    \$\begingroup\$ @winny - After some probing I think that the device is a N-channel MOSFET. More about this on the question update. \$\endgroup\$ May 21, 2019 at 12:36

1 Answer 1


It's an IRLML0060TRPbF N-channel MOSFET

Maybe, anyway.

From the International Rectifier (now Infineon) datasheet, it matches your pinout:

IRLML0060TRPbF pin-out

And the markings seem very familiar, too:

IRLML0060TRPbF markings

L̲E̲F̅B̅V (your markings) would make the device:

  • IRLML0060 N-channel MOSFET
  • Produced in 2005 / 2015 week 32
  • Lot BV
  • Copper-wired
  • Halogen-free
  • Lead-free

The only thing that isn't 100% matching up is the overline on the (first letter of the lot code), I can't find any reference to that in the datasheet.


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