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SMD code LOp

Marking codes are not standardised, and the same code is reused by unrelated makers for unrelated parts. Below is every part in our tables printed with it, and any printed with a code that is easy to misread as it, from the manufacturers' own marking tables and published code lists.

The last letter, p, is lower case, which on NXP and Philips parts is a date or factory code, so it was set aside and LO was searched.

27 parts are printed LOp

Not sure which one you have?

Answer up to 4 quick questions and these 27 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • 2SC2712-OSOT-23Transistor, 3 pins, YFWTransistorSOT-233 pinsYFW
    What it is
    Transistor
    Maker
    YFW
    Package
    SOT-23
    Pins
    3
    Details
    Bipolar transistor
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: Bipolar transistor.

  • BF775SOT-23RF transistor, 3 pins, InfineonRF transistorSOT-233 pinsInfineon
    What it is
    RF transistor
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: Bipolar transistor.

  • KTC4075WSOT-323NPN transistor, 3 pins, Galaxy MicroelectronicsNPN transistorSOT-3233 pinsGalaxy Microelectronics
    What it is
    NPN transistor
    Maker
    Galaxy Microelectronics
    Package
    SOT-323
    Pins
    3
    Details
    50V, 0.15A, General Purpose NPN Bipolar Transistor
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: NPN transistor.

  • 2SC2712OSOT-233 pins, Micro Commercial ComponentsNot recordedSOT-233 pinsMicro Commercial Components
    What it is
    Not recorded
    Maker
    Micro Commercial Components
    Package
    SOT-23
    Pins
    3
    Details
    npn gp hfe 70-140 comp 2SA1162
    Source
    Published code list

    Is it dead? The meter test is below: This part.

  • 2SC4116-OSOT-323NPN transistor, 3 pins, ToshibaNPN transistorSOT-3233 pinsToshiba
    What it is
    NPN transistor
    Maker
    Toshiba
    Package
    SOT-323
    Pins
    3
    Details
    Si-npn: GP, AF, 50V, 150mA, 100mW, B=70..140, >80MHz
    Source
    Published code list

    Is it dead? The meter test is below: NPN transistor.

  • 2SC4116OSOT-3233 pins, ToshibaNot recordedSOT-3233 pinsToshiba
    What it is
    Not recorded
    Maker
    Toshiba
    Package
    SOT-323
    Pins
    3
    Source
    Published code list

    Is it dead? The meter test is below: This part.

  • AX6603-110Z6DFNLDO regulator, AXElite TechnologyLDO regulatorDFNNot recordedAXElite Technology
    What it is
    LDO regulator
    Maker
    AXElite Technology
    Package
    DFN
    Pins
    Not recorded
    Details
    Linear voltage regulator IC: LDO, 1.1V±2%, 300mA, +CE
    Source
    Published code list

    Is it dead? The meter test is below: Voltage regulator.

  • BF775WSOT-3233 pinsNot recordedSOT-3233 pinsNot recorded
    What it is
    Not recorded
    Maker
    Not recorded
    Package
    SOT-323
    Pins
    3
    Details
    BFQ69
    Source
    Published code list

    Is it dead? The meter test is below: This part.

  • BL8566-OCR6SOT-23-6LDO regulator, 6 pins, Analog IntegrationsLDO regulatorSOT-23-66 pinsAnalog Integrations
    What it is
    LDO regulator
    Maker
    Analog Integrations
    Package
    SOT-23-6
    Pins
    6
    Details
    Linear voltage regulator IC: LDO, Dual output, Vout1/Vout2=2.8V/2.8V±2%, 300mA, +CE
    Source
    Published code list

    Is it dead? The meter test is below: Voltage regulator.

  • BSR174SOT-233 pins, PhilipsNot recordedSOT-233 pinsPhilips
    What it is
    Not recorded
    Maker
    Philips
    Package
    SOT-23
    Pins
    3
    Details
    equivalent BSJ174
    Source
    Published code list

    Is it dead? The meter test is below: This part.

  • HAC2712OSOT-23NPN transistor, 3 pins, Hottech ElectronicsNPN transistorSOT-233 pinsHottech Electronics
    What it is
    NPN transistor
    Maker
    Hottech Electronics
    Package
    SOT-23
    Pins
    3
    Details
    NPN transistor: AF-Amp, 60V, 150mA, 150mW, B=70..140, >80MHz
    Source
    Published code list

    Is it dead? The meter test is below: NPN transistor.

  • HSMP-3860SOT-233 pins, Agilent TechnologiesNot recordedSOT-233 pinsAgilent Technologies
    What it is
    Not recorded
    Maker
    Agilent Technologies
    Package
    SOT-23
    Pins
    3
    Details
    dual series pin diode
    Source
    Published code list

    Is it dead? The meter test is below: PIN diode or varicap.

  • 3 more parts have no package on record
    • TCR2LN27LDO regulator, ToshibaLDO regulatorNot recordedNot recordedToshiba
      What it is
      LDO regulator
      Maker
      Toshiba
      Package
      Not recorded
      Pins
      Not recorded
      Details
      TCR2LN series
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Voltage regulator.

    • AX6603-110BTLDO regulator, AXElite TechnologyLDO regulatorNot recordedNot recordedAXElite Technology
      What it is
      LDO regulator
      Maker
      AXElite Technology
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 1.1V±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

    • AX6603-110SCLDO regulator, AXElite TechnologyLDO regulatorNot recordedNot recordedAXElite Technology
      What it is
      LDO regulator
      Maker
      AXElite Technology
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 1.1V±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

Is it dead? One meter test per kind

Parts of the same kind are tested the same way, so each test is here once. Each part above points to its own.

Bipolar transistor

Diode range, part lifted or its base leg off the pad.

Working, it reads

From the base, one probe colour reads about 0.6 to 0.75 V to the emitter and to the collector, and open the other way round. Collector to emitter reads open both ways.

Dead, it reads

  • Collector to emitter the same both ways, near 0 V with a continuous beep: shorted. The commonest failure.
  • The base the same both ways to another pin, near 0 V or a middling value: a shorted junction.
  • Only one junction reads, or none: a junction has failed open. It then looks like a diode.
  • A reading the wrong way round, where it should be open: leaky.
On the board
this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
Watch for:
A pair of diodes with a common pin reads just like a transistor, and some transistors carry a built-in diode or resistor. The datasheet says which.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

NPN transistor

Diode range, part lifted or its base leg off the pad.

Working, it reads

Red probe on the base reads about 0.6 to 0.75 V to the emitter and to the collector, and open the other way round. Collector to emitter reads open both ways.

Dead, it reads

  • Collector to emitter the same both ways, near 0 V with a continuous beep: shorted. The commonest failure.
  • The base the same both ways to another pin, near 0 V or a middling value: a shorted junction.
  • Only one junction reads, or none: a junction has failed open. It then looks like a diode.
  • A reading the wrong way round, where it should be open: leaky.
On the board
this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
Watch for:
A pair of diodes with a common pin reads just like a transistor, and some transistors carry a built-in diode or resistor. The datasheet says which.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

Voltage regulator

Voltage, board powered, black probe on ground. Then ohms with the power off.

Working, it reads

Input pin at the supply, output pin at its rated voltage, and the enable pin high if it has one.

Dead, it reads

  • Output equal to the input: the pass element has shorted. Everything after it may have taken the full input.
  • Input present, enable high, no output: failed open, or holding itself off into a shorted load. Power off and measure output to ground.
  • Power off, input to output near 0 Ω: shorted.
On the board:
An output at 0 V is often a shorted load with the regulator in current limit. Lift the output pin: if the short stays on the board, the regulator may be fine.
Compare:
The same regulator on another rail or another board shows the right voltages and the right resistances.
Watch for:
Makers put input, output and ground on different pins in the same package, so take them from this part's datasheet. Diode or ohms readings between its pins say little; check it powered.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

This part

Diode range and ohms range, part lifted.

Working, it reads

Depends on what it is. The datasheet, or an identical part, says.

Dead, it reads

  • Between two pins, the same reading both ways, near 0 V with a continuous beep: shorted.
  • Open between every pair of pins: failed open, or a part that reads open when working.
On the board
this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

PIN diode or varicap

Diode range, part lifted or one leg off the pad. Red probe on the anode.

Working, it reads

About 0.6 to 0.9 V anode to cathode, and open the other way.

Dead, it reads

  • The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
  • Open both ways: failed open.
On the board
this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
Watch for:
A varicap that has drifted in capacitance reads normal on a meter. Only a capacitance meter or the tuning itself shows it.

A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.

Printed with a code easy to misread as LOp

One character differs, and it is one that is easy to confuse under a lamp. Each code has a page of its own.

Codes not listed here are printed on 186 more parts.

Did you find your part?

Open this in the search to correct a character or try another package.