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SMD code search: identify a part by its marking

2 parts are printed TO4. 42 printed with a similar-looking code.

Not sure which one you have?

Answer up to 4 quick questions and these 2 parts are ranked, with a meter test that settles it. It works on a dead part too.

NPN transistor, all SOT-23, 3 pins. What differs:

  • PMBS3904SOT-23NXPNXP
    What it is
    NPN transistor
    Maker
    NXP
    Package
    SOT-23
    Pins
    3
    Details
    Bipolar transistor, 40 V, 0.2 A
    Source
    Published code list

    Is it dead?

    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.

  • PMBT3904SOT-23NexperiaNexperia
    What it is
    NPN transistor
    Maker
    Nexperia
    Package
    SOT-23
    Pins
    3
    Details
    Bipolar transistor, 40 V, 0.2 A
    Source
    An older or alternative marking, from a published code list

    Is it dead?

    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.

42 more parts are printed with a code easy to misread as TO4

Printed with a code easy to misread

One character differs, and it is one that is easy to confuse under a lamp. The odd one out is marked on each.

  • NC7ST04P5printed T04SOT-23-5Logic gate, 5 pins, onsemiLogic gateSOT-23-55 pinsonsemi

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Logic gate
    Maker
    onsemi
    Package
    SOT-23-5
    Pins
    5
    Details
    TinyLogic HST Inverter
    Source
    Manufacturer datasheet

    Is it dead?

    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.

  • ESD2020D4V5printed T04DFNESD protection diode, YFWESD protection diodeDFNNot recordedYFW

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    ESD protection diode
    Maker
    YFW
    Package
    DFN
    Pins
    Not recorded
    Source
    Manufacturer datasheet

    Is it dead?

    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.

  • 2N7002KT1Gprinted 704SOT-233 pins, onsemiNot recordedSOT-233 pinsonsemi

    Printed 704 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    onsemi
    Package
    SOT-23
    Pins
    3
    Source
    Published code list

    Is it dead?

    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.

  • BZX84-A11printed t04SOT-23Zener diode, 3 pins, NXPZener diodeSOT-233 pinsNXP

    Printed t04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Zener diode
    Maker
    NXP
    Package
    SOT-23
    Pins
    3
    Details
    11 V ±1% voltage regulator (Zener) diode
    Source
    Published code list

    Is it dead?

    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.

  • ELM7334NAB1Aprinted 7D4SOT-23-5Voltage supervisor, 5 pins, ELM TechnologyVoltage supervisorSOT-23-55 pinsELM Technology

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Voltage supervisor
    Maker
    ELM Technology
    Package
    SOT-23-5
    Pins
    5
    Details
    Voltage detector IC: 3.4V±1.2%, -Reset ODO
    Source
    Published code list

    Is it dead?

    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.

  • ELM98104ACprinted 704SOT-893 pins, ELM TechnologyNot recordedSOT-893 pinsELM Technology

    Printed 704 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    ELM Technology
    Package
    SOT-89
    Pins
    3
    Details
    Linear voltage regulator IC: 10.4V±2%, 200mA
    Source
    Published code list

    Is it dead?

    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.

  • HD74LV2GT04AUSprinted T04SSOPRenesasNot recordedSSOPNot recordedRenesas

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    Renesas
    Package
    SSOP
    Pins
    Not recorded
    Details
    CMOS logic IC: Triple inverter
    Source
    Published code list

    Is it dead?

    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.

  • IXD3236F34CER-Gprinted 7D4USP-6CDC-DC converter, 6 pins, IXYSDC-DC converterUSP-6C6 pinsIXYS

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    IXYS
    Package
    USP-6C
    Pins
    6
    Details
    DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
    Source
    Published code list

    Is it dead?

    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.

  • IXD3236F34CMR-Gprinted 7D4SOT-23-5DC-DC converter, 5 pins, IXYSDC-DC converterSOT-23-55 pinsIXYS

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    IXYS
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
    Source
    Published code list

    Is it dead?

    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.

  • IXD4902NA31ER-Gprinted TD4USP-6C6 pins, IXYSNot recordedUSP-6C6 pinsIXYS

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    IXYS
    Package
    USP-6C
    Pins
    6
    Details
    Linear voltage regulator IC: -10.3V±1.5%, 500mA, soft start
    Source
    Published code list

    Is it dead?

    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.

  • NC7ST04Pprinted T04SOT-3535 pins, Fairchild SemiconductorNot recordedSOT-3535 pinsFairchild Semiconductor

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    Fairchild Semiconductor
    Package
    SOT-353
    Pins
    5
    Details
    CMOS logic IC: Single inverter
    Source
    Published code list

    Is it dead?

    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.

  • PMSS3904printed t04SOT-323NPN transistor, 3 pins, NXPNPN transistorSOT-3233 pinsNXP

    Printed t04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    NPN transistor
    Maker
    NXP
    Package
    SOT-323
    Pins
    3
    Details
    Bipolar transistor, 40 V, 0.2 A
    Source
    Published code list

    Is it dead?

    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.

  • R1191N104Dprinted 704SOT-23-5LDO regulator, 5 pins, RicohLDO regulatorSOT-23-55 pinsRicoh

    Printed 704 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    LDO regulator
    Maker
    Ricoh
    Package
    SOT-23-5
    Pins
    5
    Details
    Linear voltage regulator IC: LDO, 10.4V±1.5%, 300mA, +CE, ECO, CL
    Source
    Published code list

    Is it dead?

    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.

  • STM704printed 704SOIC-88 pins, STMicroelectronicsNot recordedSOIC-88 pinsSTMicroelectronics

    Printed 704 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    STMicroelectronics
    Package
    SOIC-8
    Pins
    8
    Source
    Published code list

    Is it dead?

    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.

  • XC6111A135MRprinted 704SOT-23-5Voltage supervisor, 5 pins, TorexVoltage supervisorSOT-23-55 pinsTorex

    Printed 704 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Voltage supervisor
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    CMOS-IC: VDet 3.5V, -MR, -Reset PPO, Wt=6.25ms, Rt=3.13ms
    Source
    Published code list

    Is it dead?

    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.

  • XC6111C435MRprinted 7D4SOT-23-5Voltage supervisor, 5 pins, TorexVoltage supervisorSOT-23-55 pinsTorex

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Voltage supervisor
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    CMOS-IC: VDet 3.5V, -MR, -Reset PPO, Wt=200ms, Rt=50ms
    Source
    Published code list

    Is it dead?

    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.

  • XC6902NA31ER-Gprinted TD4USP-6C6 pins, TorexNot recordedUSP-6C6 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    Not recorded
    Maker
    Torex
    Package
    USP-6C
    Pins
    6
    Details
    Linear voltage regulator IC: -10.3V±1.5%, 500mA, soft start
    Source
    Published code list

    Is it dead?

    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.

  • XC9148A22DER-Gprinted T04USP-6CDC-DC converter, 6 pins, TorexDC-DC converterUSP-6C6 pinsTorex

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    USP-6C
    Pins
    6
    Details
    DC/DC voltage converter IC: PWM/PFM st-up, 3.0MHz, 2.2V±2%, 1.4A, CrL, CL, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9148A22DPR-Gprinted T04SOT-89-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-89-55 pinsTorex

    Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-89-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PWM/PFM step-up, 3.0MHz, 2.2V±2%, 1.4A, CrL, CL, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9148G42DER-Gprinted TD4USP-6CDC-DC converter, 6 pins, TorexDC-DC converterUSP-6C6 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    USP-6C
    Pins
    6
    Details
    DC/DC voltage converter IC: PWM/PFM st-up, 3.0MHz, 4.2V±2%, 1.4A, ULVO, CrL, CL, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9148G42DPR-Gprinted TD4SOT-89-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-89-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-89-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PWM/PFM step-up, 3.0MHz, 4.2V±2%, 1.4A, ULVO, CrL, CL, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9225A3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 600mA, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9225B3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 600mA, -CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9225C3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 600mA, +CE, PDR
    Source
    Published code list

    Is it dead?

    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.

  • XC9225D3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 600mA, -CE, PUR
    Source
    Published code list

    Is it dead?

    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.

  • XC9225E3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 900mA, +CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9225F3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 900mA, -CE
    Source
    Published code list

    Is it dead?

    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.

  • XC9225G3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 900mA, +CE, PDR
    Source
    Published code list

    Is it dead?

    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.

  • XC9225H3E6Mprinted TD4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed TD4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PW M st-dwn, 600kHz, 3.45V±1%, 900mA, -CE, PUR
    Source
    Published code list

    Is it dead?

    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.

  • XC9236F34CER-Gprinted 7D4USP-6CDC-DC converter, 6 pins, TorexDC-DC converterUSP-6C6 pinsTorex

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    USP-6C
    Pins
    6
    Details
    DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
    Source
    Published code list

    Is it dead?

    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.

  • XC9236F34CMR-Gprinted 7D4SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex

    Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

    What it is
    DC-DC converter
    Maker
    Torex
    Package
    SOT-23-5
    Pins
    5
    Details
    DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
    Source
    Published code list

    Is it dead?

    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.

  • 11 more parts have no package on record
    • NTB0104UKprinted t04Logic level translator, NXPLogic level translatorNot recordedNot recordedNXP

      Printed t04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Logic level translator
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      1 General description
      Source
      Manufacturer datasheet

      Is it dead?

      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.

    • NTB0104UK-Q100printed t04Logic level translator, NXPLogic level translatorNot recordedNot recordedNXP

      Printed t04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Logic level translator
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Dual supply translating transceiver; auto direction sensing; 3-state
      Source
      Manufacturer datasheet

      Is it dead?

      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.

    • 74HC3TG04GDprinted T04NXPNot recordedNot recordedNot recordedNXP

      Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Not recorded
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: Triple unbuffered inverter
      Source
      Published code list

      Is it dead?

      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.

    • 74HCT1G04GVprinted T04NXPNot recordedNot recordedNot recordedNXP

      Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Not recorded
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: Single inverter
      Source
      Published code list

      Is it dead?

      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.

    • 74HCT2G04GVprinted T04NXPNot recordedNot recordedNot recordedNXP

      Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Not recorded
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: Dual inverter
      Source
      Published code list

      Is it dead?

      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.

    • 74HCT3G04DCprinted T04NXPNot recordedNot recordedNot recordedNXP

      Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Not recorded
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: Triple inverter
      Source
      Published code list

      Is it dead?

      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.

    • 74HCT3G04DPprinted T04NXPNot recordedNot recordedNot recordedNXP

      Printed T04 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      Not recorded
      Maker
      NXP
      Package
      Not recorded
      Pins
      Not recorded
      Details
      CMOS logic IC: Triple inverter
      Source
      Published code list

      Is it dead?

      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.

    • IXD3236F34C0R-Gprinted 7D4DC-DC converter, IXYSDC-DC converterNot recordedNot recordedIXYS

      Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      DC-DC converter
      Maker
      IXYS
      Package
      Not recorded
      Pins
      Not recorded
      Details
      DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
      Source
      Published code list

      Is it dead?

      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.

    • IXD3236F34C4R-Gprinted 7D4DC-DC converter, IXYSDC-DC converterNot recordedNot recordedIXYS

      Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      DC-DC converter
      Maker
      IXYS
      Package
      Not recorded
      Pins
      Not recorded
      Details
      DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
      Source
      Published code list

      Is it dead?

      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.

    • XC9236F34C0R-Gprinted 7D4DC-DC converter, TorexDC-DC converterNot recordedNot recordedTorex

      Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      DC-DC converter
      Maker
      Torex
      Package
      Not recorded
      Pins
      Not recorded
      Details
      DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
      Source
      Published code list

      Is it dead?

      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.

    • XC9236F34C4R-Gprinted 7D4DC-DC converter, TorexDC-DC converterNot recordedNot recordedTorex

      Printed 7D4 on the part. Easy to misread as TO4. Check that character with a loupe before you order anything.

      What it is
      DC-DC converter
      Maker
      Torex
      Package
      Not recorded
      Pins
      Not recorded
      Details
      DC/DC voltage converter IC: PWM/PFM, st-dwn, 3.4V±2%, 600mA, 1.2MHz, Vin>1.8V, HSST, CL
      Source
      Published code list

      Is it dead?

      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.

115 more parts have codes that begin with TO4

Codes that begin with TO4

For a marking with its end worn or burnt off. Each one shows its full printed code.

  • CJT04N15printed T04N15SOT-223N-channel MOSFET, 4 pins, JSCJN-channel MOSFETSOT-2234 pinsJSCJ

    Printed T04N15. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

    What it is
    N-channel MOSFET
    Maker
    JSCJ
    Package
    SOT-223
    Pins
    4
    Details
    MOSFET, N-channel, 150 V, 4 A
    Source
    Manufacturer datasheet

    Is it dead?

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

    Working, it reads

    Red probe on the source, black on the drain: about 0.4 to 0.9 V, the body diode. Open the other way. The gate reads open to both other pins, both ways.

    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. Often all three pins end up shorted together.
    • No body diode at all: failed open.
    On the board
    the gate usually has a resistor to the source, so gate to source reads that resistor, which is not a fault. A drain short can be the load. 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.

  • SSFT04N15printed T04N15SOT-223N-channel MOSFET, 4 pins, Good-ArkN-channel MOSFETSOT-2234 pinsGood-Ark

    Printed T04N15. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

    What it is
    N-channel MOSFET
    Maker
    Good-Ark
    Package
    SOT-223
    Pins
    4
    Details
    N-channel MOSFET, 150 V
    Source
    Manufacturer datasheet

    Is it dead?

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

    Working, it reads

    Red probe on the source, black on the drain: about 0.4 to 0.9 V, the body diode. Open the other way. The gate reads open to both other pins, both ways.

    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. Often all three pins end up shorted together.
    • No body diode at all: failed open.
    On the board
    the gate usually has a resistor to the source, so gate to source reads that resistor, which is not a fault. A drain short can be the load. 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.

  • TLV9041IDBVprinted T041SOT-23-5Operational amplifier, 5 pins, Texas InstrumentsOperational amplifierSOT-23-55 pinsTexas Instruments

    Printed T041. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

    What it is
    Operational amplifier
    Maker
    Texas Instruments
    Package
    SOT-23-5
    Pins
    5
    Details
    1.2V Ultra Low Voltage, 10µA Micro-Power RRIO Amplifier for Power Conscious Applications
    Source
    Manufacturer datasheet

    Is it dead?

    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.

  • AZ7043RTRprinted 7043RSOT-893 pins, Diodes IncorporatedNot recordedSOT-893 pinsDiodes Incorporated

    Printed 7043R. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

    What it is
    Not recorded
    Maker
    Diodes Incorporated
    Package
    SOT-89
    Pins
    3
    Details
    voltage detector 4.3V oc output
    Source
    Published code list

    Is it dead?

    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.

  • AZ7047RTRprinted 7047RSOT-893 pins, Diodes IncorporatedNot recordedSOT-893 pinsDiodes Incorporated

    Printed 7047R. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

    What it is
    Not recorded
    Maker
    Diodes Incorporated
    Package
    SOT-89
    Pins
    3
    Details
    voltage detector 4.7V oc output
    Source
    Published code list

    Is it dead?

    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.

  • 1 more part has no package on record
    • TLV9042IDDFprinted T042Operational amplifier, 8 pins, Texas InstrumentsOperational amplifierNot recorded8 pinsTexas Instruments

      Printed T042. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.

      What it is
      Operational amplifier
      Maker
      Texas Instruments
      Package
      Not recorded
      Pins
      8
      Details
      1.2V Ultra Low Voltage, 10µA Micro-Power RRIO Amplifier for Power Conscious Applications
      Source
      Manufacturer datasheet

      Is it dead?

      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.

109 more parts are not listed here. Type more of the code to narrow the list.

Did you find your part?

One code, several parts

Marking codes are not unique. In the standard code book, 6H on a SOT-23 is an NPN transistor, a varicap, an N-channel JFET, two digital transistors, a 3.6 V voltage detector: six parts from five makers. So a search shows the parts we hold under that code and under codes easily misread as it, with only the columns that tell them apart.

6Hon a SOT-23, in the code book
  • NPN transistor
  • Varicap
  • N-channel JFET
  • Digital transistor ×2
  • 3.6 V voltage detector

When more than one is left

Tap Help me choose. Up to 4 quick answers: whether the part has failed, then what separates the parts left. Those get ranked with the reasoning and a test that settles it. That uses one identification: 2 a month are free without an account, and 3 with a free account.

When you cannot read it

Tap the camera in the field. We read the characters, keep the ones we are unsure of, and search every reading. A photo too soft to read is turned back on your phone first; if it is the only one you can get, you can still send it.

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