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SMD code 1P

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.

10 parts are printed 1P

Not sure which one you have?

Answer up to 4 quick questions and these 10 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • BC847PNSOT-363Transistor, 6 pins, Infineon
    What it is
    Transistor
    Maker
    Infineon
    Package
    SOT-363
    Pins
    6
    Details
    SMD General Purpose NPN+PNP Transistors
    Source
    From the manufacturer's datasheet

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

  • BZD27B27P-MSOD-123FZener diode, 2 pins, Vishay
    What it is
    Zener diode
    Maker
    Vishay
    Package
    SOD-123F
    Pins
    2
    Details
    27 V Zener diode
    Source
    From the manufacturer's datasheet

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

  • MM3Z5V6SOD-323Zener diode, 2 pins, Diotec
    What it is
    Zener diode
    Maker
    Diotec
    Package
    SOD-323
    Pins
    2
    Details
    SMD Planar Zener Diodes
    Source
    From the manufacturer's datasheet

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

  • MMBT2222ASOT-23NPN transistor, 3 pins, Infineon
    What it is
    NPN transistor
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Details
    75 V NPN small-signal transistor
    Source
    From the manufacturer's datasheet

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

  • MMBT2222AHSOT-23NPN transistor, 3 pins, Taiwan Semiconductor
    What it is
    NPN transistor
    Maker
    Taiwan Semiconductor
    Package
    SOT-23
    Pins
    3
    Source
    From the manufacturer's datasheet

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

  • MMBT2222AMSOT-723NPN transistor, 3 pins, JSCJ
    What it is
    NPN transistor
    Maker
    JSCJ
    Package
    SOT-723
    Pins
    3
    Details
    Bipolar transistor, NPN, 40 V, 0.5 A
    Source
    From the manufacturer's datasheet

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

  • PMBT2222ASOT-23NPN transistor, 3 pins, Nexperia
    What it is
    NPN transistor
    Maker
    Nexperia
    Package
    SOT-23
    Pins
    3
    Pinout
    • 1 base
    • 2 emitter
    • 3 collector
    Details
    40 V, 600 mA NPN switching transistor
    Source
    From the manufacturer's datasheet

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

  • PMEG6002EJSOD-323Schottky diode, 2 pins, Nexperia
    What it is
    Schottky diode
    Maker
    Nexperia
    Package
    SOD-323
    Pins
    2
    Details
    60 V, 0.2 A low VF Schottky barrier rectifier
    Source
    From the manufacturer's datasheet

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

  • 2 more parts have no package on record
    • MMBT2222ATNPN transistor, JSCJ
      What it is
      NPN transistor
      Maker
      JSCJ
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Bipolar transistor, NPN, 40 V, 0.6 A
      Source
      From the manufacturer's datasheet

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

    • SMBT2222ATransistor, Infineon
      What it is
      Transistor
      Maker
      Infineon
      Package
      Not recorded
      Pins
      Not recorded
      Source
      From the manufacturer's datasheet

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

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.

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.

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.

Schottky diode

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

Working, it reads

About 0.15 to 0.45 V anode to cathode, roughly half a silicon diode, 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.
  • A reading the wrong way round as well: leaky.
  • 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 large Schottky can read about 0.1 V forward and beep like a short, and leaks a little the wrong way when good, more when warm. It is shorted only if it reads the same both ways. Measure it cold, beside an identical cold one.

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 1P

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

Codes that begin with 1P

For a marking with its end worn or burnt off. Each code has a page of its own.

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