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SMD code AUs

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, s, is lower case, which on NXP and Philips parts is a date or factory code, so it was set aside and AU was searched.

97 parts are printed AUs

Not sure which one you have?

Answer up to 4 quick questions and these 50 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • BCW60GRSOT-233 pins, Ferranti SemiconductorsNot recordedSOT-233 pinsFerranti Semiconductors
    What it is
    Not recorded
    Maker
    Ferranti Semiconductors
    Package
    SOT-23
    Pins
    3
    Details
    BCY58
    Source
    Published code list

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

  • BCX70GRSOT-233 pins, InfineonNot recordedSOT-233 pinsInfineon
    What it is
    Not recorded
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Details
    Si-npn: AF, 45V, 200mA, 330mW, B=120..220, >250MHz
    Source
    Published code list

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

  • BCX70RGSOT-233 pins, InfineonNot recordedSOT-233 pinsInfineon
    What it is
    Not recorded
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Details
    Si-npn: GP, 45V, 100mA, 330mW, B= 120..220, 250MHz
    Source
    Published code list

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

  • BFP540ESDSOT-3434 pins, InfineonNot recordedSOT-3434 pinsInfineon
    What it is
    Not recorded
    Maker
    Infineon
    Package
    SOT-343
    Pins
    4
    Details
    npn microwave fT 30GHz ESD protected BFP540
    Source
    Published code list

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

  • EC76SMAJ9.0SMATVS diode, 2 pins, E-CMOSTVS diodeSMA2 pinsE-CMOS
    What it is
    TVS diode
    Maker
    E-CMOS
    Package
    SMA
    Pins
    2
    Details
    Transient voltage supressor: Vbr=10.0..12.2V, Vrwm=9.0V, Ipp=23.7A, 400W(1ms)
    Source
    Published code list

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

  • EC76SMBJ9.0CSMBTVS diode, 2 pins, E-CMOSTVS diodeSMB2 pinsE-CMOS
    What it is
    TVS diode
    Maker
    E-CMOS
    Package
    SMB
    Pins
    2
    Details
    Transient voltage supressor: Vbr=10.0..12.2V, Vrwm=9.0V, Ipp=35.5A, 600W(1ms), Bidir.
    Source
    Published code list

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

  • IMP812JEUS-TSOT-1434 pins, IMPNot recordedSOT-1434 pinsIMP
    What it is
    Not recorded
    Maker
    IMP
    Package
    SOT-143
    Pins
    4
    Details
    CMOS-IC: Voltage Detector 4V, MR, Reset ODO, 140ms
    Source
    Published code list

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

  • MAX825TEUKSOT-23-55 pins, Analog DevicesNot recordedSOT-23-55 pinsAnalog Devices
    What it is
    Not recorded
    Maker
    Analog Devices
    Package
    SOT-23-5
    Pins
    5
    Details
    CMOS-IC: Voltage Detector 3,08V, MR, ±Reset Push-pull output
    Source
    Published code list

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

  • MIC803-46D4VC3SOT-3233 pins, MicrelNot recordedSOT-3233 pinsMicrel
    What it is
    Not recorded
    Maker
    Micrel
    Package
    SOT-323
    Pins
    3
    Details
    Microprocessor reset circuit
    Source
    Published code list

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

  • MIC803-46D4VM3SOT-23Voltage supervisor, 3 pins, MicrelVoltage supervisorSOT-233 pinsMicrel
    What it is
    Voltage supervisor
    Maker
    Micrel
    Package
    SOT-23
    Pins
    3
    Details
    Microprocessor reset circuit
    Source
    Published code list

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

  • 5 more parts have no package on record
    • BFP540FESD4 pins, InfineonNot recordedNot recorded4 pinsInfineon
      What it is
      Not recorded
      Maker
      Infineon
      Package
      Not recorded
      Pins
      4
      Source
      Published code list

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

    • IXD1504A3517R-GLDO regulator, IXYSLDO regulatorNot recordedNot recordedIXYS
      What it is
      LDO regulator
      Maker
      IXYS
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 3.5V±1%, 150mA, +CE
      Source
      Published code list

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

    • IXD5127C45FNRVoltage supervisor, IXYSVoltage supervisorNot recordedNot recordedIXYS
      What it is
      Voltage supervisor
      Maker
      IXYS
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Voltage detector IC: 4.5V±0.8%, +Reset PPO, -MR, 50ms Rt delay
      Source
      Published code list

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

    • IXD5127N46ANRVoltage supervisor, IXYSVoltage supervisorNot recordedNot recordedIXYS
      What it is
      Voltage supervisor
      Maker
      IXYS
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Voltage detector IC: 4.6V±0.8%, -Reset ODO, -MR, 50ms Rt delay
      Source
      Published code list

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

    • NC7SV19LFairchild SemiconductorNot recordedNot recordedNot recordedFairchild Semiconductor
      What it is
      Not recorded
      Maker
      Fairchild Semiconductor
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: 1-of-2 decoder/demultiplexer
      Source
      Published code list

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

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.

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.

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.

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.

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.

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