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SMD code 25

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.

15 parts are printed 25

Not sure which one you have?

Answer up to 4 quick questions and these 15 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • BZX384-A6V2SOD-323Zener diode, 2 pins, Nexperia
    What it is
    Zener diode
    Maker
    Nexperia
    Package
    SOD-323
    Pins
    2
    Source
    From the manufacturer's datasheet

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

  • DTC124ECASOT-23Digital transistor (NPN, resistors built in), 3 pins, JSCJ
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    JSCJ
    Package
    SOT-23
    Pins
    3
    Details
    Digital transistor (bias resistors built in), NPN
    Source
    From the manufacturer's datasheet

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

  • DTC124EE3SOT-416Digital transistor (NPN, resistors built in), 3 pins, ROHM
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    ROHM
    Package
    SOT-416
    Pins
    3
    Details
    NPN digital transistor (bias resistor built-in); R1 = 22kOhm, R2 = 22kOhm
    Source
    From the manufacturer's datasheet

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

  • DTC124EEBSOT-416Digital transistor (NPN, resistors built in), 3 pins, ROHM
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    ROHM
    Package
    SOT-416
    Pins
    3
    Details
    NPN digital transistor (bias resistor built-in); R1 = 22kOhm, R2 = 22kOhm
    Source
    From the manufacturer's datasheet

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

  • DTC124EKASOT-23Digital transistor (NPN, resistors built in), 3 pins, ROHM
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    ROHM
    Package
    SOT-23
    Pins
    3
    Details
    NPN digital transistor (bias resistor built-in); R1 = 22kOhm, R2 = 22kOhm
    Source
    From the manufacturer's datasheet

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

  • DTC124EMSOT-723Digital transistor (NPN, resistors built in), 3 pins, JSCJ
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    JSCJ
    Package
    SOT-723
    Pins
    3
    Details
    Digital transistor (bias resistors built in), NPN
    Source
    From the manufacturer's datasheet

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

  • DTC124EU3SOT-323Digital transistor (NPN, resistors built in), 3 pins, ROHM
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    ROHM
    Package
    SOT-323
    Pins
    3
    Details
    NPN digital transistor (bias resistor built-in); R1 = 22kOhm, R2 = 22kOhm
    Source
    From the manufacturer's datasheet

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

  • DTC124EUASOT-323Digital transistor (NPN, resistors built in), 3 pins, JSCJ
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    JSCJ
    Package
    SOT-323
    Pins
    3
    Details
    Digital transistor (bias resistors built in), NPN
    Source
    From the manufacturer's datasheet

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

  • DTC124EUBSOT-323Digital transistor (NPN, resistors built in), 3 pins, ROHM
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    ROHM
    Package
    SOT-323
    Pins
    3
    Details
    NPN digital transistor (bias resistor built-in); R1 = 22kOhm, R2 = 22kOhm
    Source
    From the manufacturer's datasheet

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

  • PDTC123JTSOT-23Digital transistor (NPN, resistors built in), 3 pins, Nexperia
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Nexperia
    Package
    SOT-23
    Pins
    3
    Details
    50 V, 100 mA NPN resistor-equipped transistor; R1 = 2.2 kΩ, R2 = 47 kΩ
    Source
    From the manufacturer's datasheet

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

  • TSM250N02CXSOT-23MOSFET, 3 pins, Taiwan Semiconductor
    What it is
    MOSFET
    Maker
    Taiwan Semiconductor
    Package
    SOT-23
    Pins
    3
    Source
    From the manufacturer's datasheet

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

  • EIA-96:250603Precision resistor (EIA-96 code), 2 pins
    What it is
    Precision resistor (EIA-96 code)
    Maker
    Not recorded
    Package
    0603
    Pins
    2
    Details
    EIA-96 precision chip resistor, significand 17.8; the printed mark adds a multiplier letter (25A = 178 Ohm, 25B = 1.78 kOhm)
    Source
    Added by hand from a published table

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

  • 3 more parts have no package on record
    • DTC124EEDigital transistor (NPN, resistors built in), JSCJ
      What it is
      Digital transistor (NPN, resistors built in)
      Maker
      JSCJ
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Digital transistor (bias resistors built in), NPN
      Source
      From the manufacturer's datasheet

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

    • SN74LVC2G125DCULogic gate, 8 pins, Texas Instruments
      What it is
      Logic gate
      Maker
      Texas Instruments
      Package
      Not recorded
      Pins
      8
      Details
      Dual Bus Buffer Gate With 3-State Outputs
      Source
      From the manufacturer's datasheet

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

    • VLIN2626-DD1ESD protection diode, Vishay
      What it is
      ESD protection diode
      Maker
      Vishay
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Single-Line Bidirectional ESD-Protection Diode in DFN1006-2B
      Source
      From the manufacturer's datasheet

      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.

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.

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.

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.

MOSFET

Diode range, part lifted. Test drain to source first, then short gate to source and test again.

Working, it reads

One way between drain and source reads about 0.4 to 0.9 V, the body diode, and the other way open. The gate reads open to both other pins.

Dead, it reads

  • Drain to source the same both ways, near 0 V with a continuous beep, and still so after shorting gate to source: shorted. The classic failure.
  • The gate reads low to source or drain: gate shorted.
  • No body diode at all: failed open.
On the board
the gate usually has a resistor to the source, which reads as that resistor and is not a fault. Lift a leg to be sure.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
Watch for:
The diode range can charge the gate enough to turn the part on, and then drain to source reads near 0 both ways on a good part. Short gate to source and test again before you condemn it.

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.

Resistor

Ohms range, across it, power off.

Working, it reads

Its marked value, within tolerance. On the board it reads the same or lower, because everything around it sits in parallel.

Dead, it reads

  • Open: burnt, cracked, or eaten through by sulphur. The commonest failure.
  • Well above its marked value: drifted high.
  • On the board, clearly higher than its marked value: it has failed, since the board can only pull a reading down.
On the board:
A reading lower than marked on the board proves nothing; lift one end. A reading higher than marked is a fault even on the board.
Compare:
The same position on another channel usually carries the same value, and so does the matching part on another board.
Watch for:
A burnt resistor usually means the part it feeds pulled too much. Find that before fitting a new one, or it burns too. The marking, not the reading, says what to fit.

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 25

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 25

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.