Skip to content

SMD code CA in SOT-23

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.

Not sure which one you have?

Answer up to 4 quick questions and these 50 parts are ranked, with a meter test that settles it. It works on a dead part too.

all SOT-23, 3 pins. What differs:

  • LDTD114ELT1GSOT-23Digital transistor (NPN, resistors built in), LRCDigital transistor (NPN, resistors built in)LRC
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    LRC
    Package
    SOT-23
    Pins
    3
    Details
    Digital transistor (bias resistors built in), NPN, IC 500 mA, VCEO 50 V
    Source
    Manufacturer datasheet

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

  • MMBZ4691SOT-23Zener diode, Good-ArkZener diodeGood-Ark
    What it is
    Zener diode
    Maker
    Good-Ark
    Package
    SOT-23
    Pins
    3
    Details
    Zener diode, VZ 6.2 V, 0.35 W
    Source
    Manufacturer datasheet

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

  • MMBZ5257BSOT-23Zener diode, Formosa MicrosemiZener diodeFormosa Microsemi
    What it is
    Zener diode
    Maker
    Formosa Microsemi
    Package
    SOT-23
    Pins
    3
    Source
    Manufacturer datasheet

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

  • S-LDTD114ELT1GSOT-23Digital transistor (NPN, resistors built in), LRCDigital transistor (NPN, resistors built in)LRC
    What it is
    Digital transistor (NPN, resistors built in)
    Maker
    LRC
    Package
    SOT-23
    Pins
    3
    Details
    Digital transistor (bias resistors built in), NPN, IC 500 mA, VCEO 50 V
    Source
    Manufacturer datasheet

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

  • 2SA1885SOT-23ROHMNot recordedROHM
    What it is
    Not recorded
    Maker
    ROHM
    Package
    SOT-23
    Pins
    3
    Details
    Si-pnp: HF/Sw, 15V, 100mA, 650MHz
    Source
    Published code list

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

  • AP130-15WSOT-23AnachipNot recordedAnachip
    What it is
    Not recorded
    Maker
    Anachip
    Package
    SOT-23
    Pins
    3
    Details
    VR-IC: LDO, 1,5V±2%, 300mA
    Source
    Published code list

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

  • APE6809N-ASOT-23Voltage supervisor, Advanced Power ElectronicsVoltage supervisorAdvanced Power Electronics
    What it is
    Voltage supervisor
    Maker
    Advanced Power Electronics
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 4.63V±2%, -Reset PPO
    Source
    Published code list

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

  • APE6809N-HSOT-23Voltage supervisor, Advanced Power ElectronicsVoltage supervisorAdvanced Power Electronics
    What it is
    Voltage supervisor
    Maker
    Advanced Power Electronics
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 2.70V±2%, -Reset PPO
    Source
    Published code list

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

  • AX6901ARSOT-23Voltage supervisor, AXElite TechnologyVoltage supervisorAXElite Technology
    What it is
    Voltage supervisor
    Maker
    AXElite Technology
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 4.63V±1.5%, -Reset PPO
    Source
    Published code list

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

  • AX6901HRSOT-23Voltage supervisor, AXElite TechnologyVoltage supervisorAXElite Technology
    What it is
    Voltage supervisor
    Maker
    AXElite Technology
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 2.70V±1.5%, -Reset PPO
    Source
    Published code list

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

  • BB509SOT-23IntermetallNot recordedIntermetall
    What it is
    Not recorded
    Maker
    Intermetall
    Package
    SOT-23
    Pins
    3
    Source
    Published code list

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

  • BB510SOT-23ITT IntermetallNot recordedITT Intermetall
    What it is
    Not recorded
    Maker
    ITT Intermetall
    Package
    SOT-23
    Pins
    3
    Details
    Capacitance diode: Dual, AM-Tuning, 10V, 440..600pF(1..9V)
    Source
    Published code list

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

  • BCW61ARSOT-23Diodes IncorporatedNot recordedDiodes Incorporated
    What it is
    Not recorded
    Maker
    Diodes Incorporated
    Package
    SOT-23
    Pins
    3
    Details
    Si-pnp: AF, 32V, 200mA, 330mW, B=120..220, >180MHz
    Source
    Published code list

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

  • BFS18SOT-23InfineonNot recordedInfineon
    What it is
    Not recorded
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Details
    Si-npn: HF, 30V, 30mA, 200MHz
    Source
    Published code list

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

  • FP6809-40NS3GSOT-23Voltage supervisor, FitipowerVoltage supervisorFitipower
    What it is
    Voltage supervisor
    Maker
    Fitipower
    Package
    SOT-23
    Pins
    3
    Details
    Voltage detector IC: 4.0V±1.5%, -Reset ODO
    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.

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.

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.

This part

Diode range and ohms range, part lifted.

Working, it reads

Depends on what it is. The datasheet, or an identical part, says.

Dead, it reads

  • Between two pins, the same reading both ways, near 0 V with a continuous beep: shorted.
  • Open between every pair of pins: failed open, or a part that reads open when working.
On the board
this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.

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

Voltage regulator

Voltage, board powered, black probe on ground. Then ohms with the power off.

Working, it reads

Input pin at the supply, output pin at its rated voltage, and the enable pin high if it has one.

Dead, it reads

  • Output equal to the input: the pass element has shorted. Everything after it may have taken the full input.
  • Input present, enable high, no output: failed open, or holding itself off into a shorted load. Power off and measure output to ground.
  • Power off, input to output near 0 Ω: shorted.
On the board:
An output at 0 V is often a shorted load with the regulator in current limit. Lift the output pin: if the short stays on the board, the regulator may be fine.
Compare:
The same regulator on another rail or another board shows the right voltages and the right resistances.
Watch for:
Makers put input, output and ground on different pins in the same package, so take them from this part's datasheet. Diode or ohms readings between its pins say little; check it powered.

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

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.

Silicon diode

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

Working, it reads

About 0.5 to 0.8 V anode to cathode, and open the other way. Small switching diodes read about 0.6 to 0.7 V; large rectifiers can read a little lower.

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: failed open.
  • A reading the wrong way round as well: 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 three-pin body can hold two diodes. With a common pin they read two junctions from that pin, just like a transistor; in series they read two drops end to end. Test each pair the datasheet names.

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 CA

One character differs, and it is one that is easy to confuse under a lamp. 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.