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SMD code BGs

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 BG was searched.

170 parts are printed BGs

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.

  • SMBG13CASMBG2 pins, VishayNot recordedSMBG2 pinsVishay
    What it is
    Not recorded
    Maker
    Vishay
    Package
    SMBG
    Pins
    2
    Details
    TVS: 13V, 27.9A, 600W(1ms), Bidirectional
    Source
    Published code list

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

  • SMBJ13CA-TSMBTVS diode, 2 pins, INPAQ TechnologyTVS diodeSMB2 pinsINPAQ Technology
    What it is
    TVS diode
    Maker
    INPAQ Technology
    Package
    SMB
    Pins
    2
    Details
    Transient voltage supressor: Vbr=14.4..15.9V, Vrwm=13V, Ipp=27.9A, 600W(1ms), Bidir.
    Source
    Published code list

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

  • SMCG78CSMCGTVS diode, 2 pins, VishayTVS diodeSMCG2 pinsVishay
    What it is
    TVS diode
    Maker
    Vishay
    Package
    SMCG
    Pins
    2
    Details
    TVS: 78V, 10.8A, 1500W (1ms), Bidirectional
    Source
    Published code list

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

  • SODJ13CA-SHSOD-123FTVS diode, 2 pins, LRCTVS diodeSOD-123F2 pinsLRC
    What it is
    TVS diode
    Maker
    LRC
    Package
    SOD-123F
    Pins
    2
    Details
    Transient voltage supressor: Vrwm=13V, Vbr=14.4..15.9V, Ipp=20A(8.3ms), 200W(1ms), Bidir.
    Source
    Published code list

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

  • TC1272ALVNBTRSOT-233 pins, MicrochipNot recordedSOT-233 pinsMicrochip
    What it is
    Not recorded
    Maker
    Microchip
    Package
    SOT-23
    Pins
    3
    Source
    Published code list

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

  • TC1302BGSVMFDFNLDO regulator, MicrochipLDO regulatorDFNNot recordedMicrochip
    What it is
    LDO regulator
    Maker
    Microchip
    Package
    DFN
    Pins
    Not recorded
    Details
    Linear voltage regulator IC: LDO, Dual out, Vo1/Vo2=2.7V(300mA)/1.5V(150mA)±2.5%, +CE
    Source
    Published code list

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

  • TFMCJ78CSMC2 pins, RectronNot recordedSMC2 pinsRectron
    What it is
    Not recorded
    Maker
    Rectron
    Package
    SMC
    Pins
    2
    Details
    TVS: 78V, 10.8A, 1500W (1ms), Bidirectional
    Source
    Published code list

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

  • TSMA20ASMATVS diode, 2 pins, VishayTVS diodeSMA2 pinsVishay
    What it is
    TVS diode
    Maker
    Vishay
    Package
    SMA
    Pins
    2
    Details
    Transient voltage supressor: Vbr=19.0..21.0V, Vrwm=17.1V, Ipp=15A, 400W(1ms)
    Source
    Published code list

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

  • TV04A130JSMA2 pins, ComchipNot recordedSMA2 pinsComchip
    What it is
    Not recorded
    Maker
    Comchip
    Package
    SMA
    Pins
    2
    Details
    TVS: 13V, 5%, 18.6A, 400W(1ms)
    Source
    Published code list

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

  • TV04A130J-GSMATVS diode, 2 pins, ComchipTVS diodeSMA2 pinsComchip
    What it is
    TVS diode
    Maker
    Comchip
    Package
    SMA
    Pins
    2
    Details
    Transient voltage supressor: Vrwm=13.0V, Vbr=14.40..15.90V, Ipp=18.60A, 400W(1ms)
    Source
    Published code list

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

  • 5 more parts have no package on record
    • SMBS13CATVS diode, Formosa MicrosemiTVS diodeNot recordedNot recordedFormosa Microsemi
      What it is
      TVS diode
      Maker
      Formosa Microsemi
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Transient voltage supressor: Vrwm=13V, Vbr=14.4..15.9V, Ipp=27.9A, 600W(1ms), Bidir.
      Source
      Published code list

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

    • SMD15KPA28CATVS diode, MDE SemiconductorTVS diodeNot recordedNot recordedMDE Semiconductor
      What it is
      TVS diode
      Maker
      MDE Semiconductor
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Transient voltage supressor: Vrwm=28.0V, Vbr=31.28V, Vcl=47.5V, Ipp=317.9A, 15000W(1ms), Bidir.
      Source
      Published code list

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

    • SMD30KPA28CATVS diode, MDE SemiconductorTVS diodeNot recordedNot recordedMDE Semiconductor
      What it is
      TVS diode
      Maker
      MDE Semiconductor
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Transient voltage supressor: Vrwm=28.0V, Vbr=31.3V, Vcl=50.0V, Ipp=606.0A, 30000W(1ms), Bidir.
      Source
      Published code list

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

    • TFZ9.1BZener diode, ROHMZener diodeNot recordedNot recordedROHM
      What it is
      Zener diode
      Maker
      ROHM
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Zener diode: 8.57..9.01V, Izt=20mA, Zzt=8, 500mW
      Source
      Published code list

      Is it dead? The meter test is below: Zener diode.

    • TFZV9.1BZener diode, ROHMZener diodeNot recordedNot recordedROHM
      What it is
      Zener diode
      Maker
      ROHM
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Zener diode: 8.57..9.01V, Izt=20mA, Zzt=8, 500mW
      Source
      Published code list

      Is it dead? The meter test is below: Zener 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.

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.

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.

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.

Zener diode

Diode range for the forward check, part lifted, red probe on the anode. A bench supply for the Zener voltage.

Working, it reads

About 0.6 to 0.8 V forward and open in reverse on the diode range. Its Zener voltage shows only on a supply: feed it through a resistor that sets about 5 mA, cathode to positive, read quickly, and it should hold near its rated voltage.

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, forward too: failed open.
  • Holds well off its rated voltage on the supply test: drifted.
  • A soft knee, or a voltage that creeps on the supply test: 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 meter's diode range stops at about 2 to 3 V, so almost every Zener reads open in reverse on it, good or bad; a 3 V meter may just show a 2.4 or 2.7 V part. Above about 3 V the meter cannot tell a Zener from a plain diode.

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

Did you find your part?

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