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SMD code OL

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.

7 parts are printed OL

Not sure which one you have?

Answer up to 4 quick questions and these 7 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • 2SA1521SOT-233 pins, Sanyo ElectricNot recordedSOT-233 pinsSanyo Electric
    What it is
    Not recorded
    Maker
    Sanyo Electric
    Package
    SOT-23
    Pins
    3
    Details
    pre-biased sw pnp comp 2SC3915
    Source
    Published code list

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

  • 2SC3736-LSOT-893 pins, NEC ElectronicsNot recordedSOT-893 pinsNEC Electronics
    What it is
    Not recorded
    Maker
    NEC Electronics
    Package
    SOT-89
    Pins
    3
    Details
    Si-npn: Sw, 60V, 1A, 2W, B=100..200, >300MHz
    Source
    Published code list

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

  • 2SC3736OLSOT-893 pins, RenesasNot recordedSOT-893 pinsRenesas
    What it is
    Not recorded
    Maker
    Renesas
    Package
    SOT-89
    Pins
    3
    Source
    Published code list

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

  • PT7M7032CHTASOT-23-5Voltage supervisor, 5 pins, Pericom TechnologyVoltage supervisorSOT-23-55 pinsPericom Technology
    What it is
    Voltage supervisor
    Maker
    Pericom Technology
    Package
    SOT-23-5
    Pins
    5
    Details
    Voltage detector IC: 3.2V±1.5%, +Reset PPO
    Source
    Published code list

    Is it dead? The meter test is below: Integrated circuit.

  • PT7M7032CHTAESOT-23-5Voltage supervisor, 5 pins, Pericom TechnologyVoltage supervisorSOT-23-55 pinsPericom Technology
    What it is
    Voltage supervisor
    Maker
    Pericom Technology
    Package
    SOT-23-5
    Pins
    5
    Details
    Voltage detector IC: 3.2V±1.5%, +Reset PPO, L-Free
    Source
    Published code list

    Is it dead? The meter test is below: Integrated circuit.

  • SM6T150CASMBTVS diode, 2 pins, MDE SemiconductorTVS diodeSMB2 pinsMDE Semiconductor
    What it is
    TVS diode
    Maker
    MDE Semiconductor
    Package
    SMB
    Pins
    2
    Details
    600 W TVS diode, bidirectional
    Source
    Published code list

    Is it dead? The meter test is below: TVS or ESD protection diode.

  • SMBJ6.0CASMBTVS diode, 2 pins, Fagor ElectronicaTVS diodeSMB2 pinsFagor Electronica
    What it is
    TVS diode
    Maker
    Fagor Electronica
    Package
    SMB
    Pins
    2
    Source
    Published code list

    Is it dead? The meter test is below: TVS or ESD protection diode.

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.

Digital transistor

Ohms range, part lifted. The datasheet gives the built-in resistors: R1 in series with the base, R2 from base to emitter.

Working, it reads

Base to emitter reads about R1 plus R2 either way round, about 20 kΩ on a 10 k and 10 k part, give or take their wide tolerance. Collector to emitter reads open. A part with no R2 reads a junction behind R1 one way instead.

Dead, it reads

  • Collector to emitter the same both ways, near 0 Ω with a continuous beep: shorted.
  • From the base, open or far above R1 plus R2: R1 has failed. Static damage shows here most often.
  • Base to emitter near 0 Ω: failed short.
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:
The readings depend on the resistor values, so an identical part elsewhere on the board is the surest reference. Measure it the same way.
Watch for:
On the diode range a good part with 10 kΩ resistors reads open on every pair, so a good part looks dead there. Use the ohms range.

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.

Integrated circuit

Voltage with the board powered; ohms from each pin to ground with it off.

Working, it reads

Supply pin at its voltage and the output doing what the datasheet says. Readings between pins depend on the part.

Dead, it reads

  • A pin near 0 Ω to ground or to the supply pin where an identical part does not read that: failed short.
  • Supply present, output stuck: failed, or its load has.
On the board:
A pin shorted to ground on the board can be anything on that net. Lift the pin to be sure.
Compare:
The surest reference is the same IC on a working board, measured pin by pin.
Watch for:
Its protection diodes can read like junctions between pins, even like a transistor. That proves nothing either way.

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

TVS or ESD protection diode

Diode range, from the protected line to ground, part lifted if you can.

Working, it reads

A one-way part reads about 0.6 to 0.8 V forward and open in reverse. A two-way part reads open both ways. Arrays with several lines read as the datasheet's diagram draws them.

Dead, it reads

  • From the line to ground, the same reading both ways, near 0 V with a continuous beep: shorted.
  • A reading both ways on a one-way part: leaky.
  • A one-way part open both ways: failed open.
On the board
, a line reading shorted to ground can be this part or anything else on that line. Lift it: if the short goes with it, it has failed.
Compare:
The same part on the next line or connector pin is the healthy reading to compare with.
Watch for:
A two-way part reads open both ways when it is good, exactly like one that has failed open. The meter cannot tell them apart; an identical part on the next line can.

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 OL

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 22 more parts.

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