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SMD code N09

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.

N09 on a chip capacitor

90 pF

90 pF capacitor

The n is both the decimal point and the unit: 90 pF.

Check it with a meter

Lift one end and measure it on a capacitance range. A good one reads close to 90 pF. In circuit the meter also sees everything connected across it, so the reading means little until it is out. A failed one usually reads near 0 Ω, or a steady low resistance, on the ohms range, often from a crack. On the board a shorted capacitor shorts its whole rail. A failed reading does not change what to fit: the marking still says 90 pF.

On a transistor or diode body (SOT-89-5, SOT-23, SOT-23-5), N09 is a part code instead. Those parts are listed below.

12 parts are printed N09

Not sure which one you have?

Answer up to 4 quick questions and these 12 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • 82N09-AE3-5SOT-23Voltage supervisor, 3 pins, UnisonicVoltage supervisorSOT-233 pinsUnisonic
    What it is
    Voltage supervisor
    Maker
    Unisonic
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 0.9V±2% -Reset ODO
    Source
    Published code list

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

  • 82N09-AF5-BSOT-23-5Voltage supervisor, 5 pins, UnisonicVoltage supervisorSOT-23-55 pinsUnisonic
    What it is
    Voltage supervisor
    Maker
    Unisonic
    Package
    SOT-23-5
    Pins
    5
    Details
    Voltage detector IC: 0.9V±2% -Reset ODO
    Source
    Published code list

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

  • ADM825xYRJ-R7SOT-23-55 pins, Analog DevicesNot recordedSOT-23-55 pinsAnalog Devices
    What it is
    Not recorded
    Maker
    Analog Devices
    Package
    SOT-23-5
    Pins
    5
    Source
    Published code list

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

  • DDTC123XCASOT-23Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-23
    Pins
    3
    Details
    dtr npn 50V 0.1A res 4k7/10k 0.2W
    Source
    Published code list

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

  • DDTC123XESOT-523Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-5233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-523
    Pins
    3
    Details
    dtr npn 50V 0.1A res 4k7/10k 0.15W
    Source
    Published code list

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

  • DDTC123XKASOT-23Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-23
    Pins
    3
    Details
    dtr npn 50V 0.1A res 4k7/10k 0.2W
    Source
    Published code list

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

  • DDTC123XUASOT-323Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-3233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-323
    Pins
    3
    Details
    dtr npn 50V 0.1A res 4k7/10k 0.2W
    Source
    Published code list

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

  • DDTC143XCASOT-23Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-23
    Pins
    3
    Details
    Si-npn-Digi: Sw, 50V, 100mA, 200mW, 250MHz, R1/R2=4k7/10k
    Source
    Published code list

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

  • DDTC143XESOT-523Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-5233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-523
    Pins
    3
    Details
    Si-npn-Digi: Sw, 50V, 100mA, 150mW, 250MHz, R1/R2=4k7/10k
    Source
    Published code list

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

  • DDTC143XKASOT-23Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-23
    Pins
    3
    Details
    Si-npn-Digi: Sw, 50V, 100mA, 200mW, 250MHz, R1/R2=4k7/10k
    Source
    Published code list

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

  • DDTC143XUASOT-323Digital transistor (NPN, resistors built in), 3 pins, Diodes IncorporatedDigital transistor (NPN, resistors built in)SOT-3233 pinsDiodes Incorporated
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    Diodes Incorporated
    Package
    SOT-323
    Pins
    3
    Details
    Si-npn-Digi: Sw, 50V, 100mA, 200mW, 250MHz, R1/R2=4k7/10k
    Source
    Published code list

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

  • RP504N091CSOT-23-5DC-DC converter, 5 pins, RicohDC-DC converterSOT-23-55 pinsRicoh
    What it is
    DC-DC converter
    Maker
    Ricoh
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PWM st-dwn, 0.9V±18mV, 600mA, 2.25MHz, +CE
    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.

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.

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.

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.

Printed with a code easy to misread as N09

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 N09

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

Did you find your part?

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