SMD code AC
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.
14 parts are printed AC
Not sure which one you have?
Answer up to 4 quick questions and these 14 parts are ranked, with a meter test that settles it. It works on a dead part too.
BCW60CSOT-23NPN transistor, 3 pins, InfineonNPN transistorSOT-233 pinsInfineon
- What it is
- NPN transistor
- Maker
- Infineon
- Package
- SOT-23
- Pins
- 3
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: NPN transistor.
BCX51-10SOT-89PNP transistor, 3 pins, InfineonPNP transistorSOT-893 pinsInfineon
- What it is
- PNP transistor
- Maker
- Infineon
- Package
- SOT-89
- Pins
- 3
- Details
- -45 V, -1 A PNP medium-power transistor, gain group 10
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: PNP transistor.
ESDBKU3V0D3SOD-323ESD protection diode, 2 pins, JSCJESD protection diodeSOD-3232 pinsJSCJ
- What it is
- ESD protection diode
- Maker
- JSCJ
- Package
- SOD-323
- Pins
- 2
- Details
- ESD protection diode, VRWM 3 V
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
MMBT3904FN3SOT-883Transistor, 3 pins, PanjitTransistorSOT-8833 pinsPanjit
- What it is
- Transistor
- Maker
- Panjit
- Package
- SOT-883
- Pins
- 3
- Details
- Bipolar transistor
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Bipolar transistor.
MMDT5112WSOT-323Digital transistor (resistors built in), 3 pins, DiotecDigital transistor (resistors built in)SOT-3233 pinsDiotec
- What it is
- Digital transistor (resistors built in)
- Maker
- Diotec
- Package
- SOT-323
- Pins
- 3
- Details
- SMD Digital PNP Transistors
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Digital transistor.
PESD5V0L1BASOD-323ESD protection diode, 2 pins, NexperiaESD protection diodeSOD-3232 pinsNexperia
- What it is
- ESD protection diode
- Maker
- Nexperia
- Package
- SOD-323
- Pins
- 2
- Details
- Low capacitance bidirectional ESD protection diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
PJGBLC08SOD-323ESD protection diode, 2 pins, PanjitESD protection diodeSOD-3232 pinsPanjit
- What it is
- ESD protection diode
- Maker
- Panjit
- Package
- SOD-323
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
PJGBLC08-AUSOD-323ESD protection diode, 2 pins, PanjitESD protection diodeSOD-3232 pinsPanjit
- What it is
- ESD protection diode
- Maker
- Panjit
- Package
- SOD-323
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
PMEG1030EHSOD-123FSchottky diode, 2 pins, NexperiaSchottky diodeSOD-123F2 pinsNexperia
- What it is
- Schottky diode
- Maker
- Nexperia
- Package
- SOD-123F
- Pins
- 2
- Details
- 10 V, 3 A ultra low VF Schottky barrier rectifier
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Schottky diode.
5 more parts have no package on record
AONC68816MOSFET, Alpha & Omega SemiconductorMOSFETNot recordedNot recordedAlpha & Omega Semiconductor
- What it is
- MOSFET
- Maker
- Alpha & Omega Semiconductor
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Medium-voltage (40-400 V) MOSFET
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: MOSFET.
BFP620FRF transistor, InfineonRF transistorNot recordedNot recordedInfineon
- What it is
- RF transistor
- Maker
- Infineon
- Package
- Not recorded
- Pins
- Not recorded
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Bipolar transistor.
BFS466L6RF transistor, InfineonRF transistorNot recordedNot recordedInfineon
- What it is
- RF transistor
- Maker
- Infineon
- Package
- Not recorded
- Pins
- Not recorded
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Bipolar transistor.
ESDU3V3AG4ESD protection diode, JSCJESD protection diodeNot recordedNot recordedJSCJ
- What it is
- ESD protection diode
- Maker
- JSCJ
- Package
- Not recorded
- Pins
- Not recorded
- Details
- ESD protection diode, VRWM 3.3 V
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
SMP3V3TVS diode, VishayTVS diodeNot recordedNot recordedVishay
- What it is
- TVS diode
- Maker
- Vishay
- Package
- Not recorded
- Pins
- Not recorded
- Details
- 400 W TVS diode, unidirectional
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
Is it dead? One meter test per kind
Parts of the same kind are tested the same way, so each test is here once. Each part above points to its own.
MOSFET
Diode range, part lifted. Test drain to source first, then short gate to source and test again.
Working, it reads
One way between drain and source reads about 0.4 to 0.9 V, the body diode, and the other way open. The gate reads open to both other pins.
Dead, it reads
- Drain to source the same both ways, near 0 V with a continuous beep, and still so after shorting gate to source: shorted. The classic failure.
- The gate reads low to source or drain: gate shorted.
- No body diode at all: failed open.
- On the board
- the gate usually has a resistor to the source, which reads as that resistor and is not a fault. Lift a leg to be sure.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- The diode range can charge the gate enough to turn the part on, and then drain to source reads near 0 both ways on a good part. Short gate to source and test again before you condemn it.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
NPN transistor
Diode range, part lifted or its base leg off the pad.
Working, it reads
Red probe on the base reads about 0.6 to 0.75 V to the emitter and to the collector, and open the other way round. Collector to emitter reads open both ways.
Dead, it reads
- Collector to emitter the same both ways, near 0 V with a continuous beep: shorted. The commonest failure.
- The base the same both ways to another pin, near 0 V or a middling value: a shorted junction.
- Only one junction reads, or none: a junction has failed open. It then looks like a diode.
- A reading the wrong way round, where it should be open: leaky.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A pair of diodes with a common pin reads just like a transistor, and some transistors carry a built-in diode or resistor. The datasheet says which.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
PNP transistor
Diode range, part lifted or its base leg off the pad.
Working, it reads
Black 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.
Bipolar transistor
Diode range, part lifted or its base leg off the pad.
Working, it reads
From the base, one probe colour reads about 0.6 to 0.75 V to the emitter and to the collector, and open the other way round. Collector to emitter reads open both ways.
Dead, it reads
- Collector to emitter the same both ways, near 0 V with a continuous beep: shorted. The commonest failure.
- The base the same both ways to another pin, near 0 V or a middling value: a shorted junction.
- Only one junction reads, or none: a junction has failed open. It then looks like a diode.
- A reading the wrong way round, where it should be open: leaky.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A pair of diodes with a common pin reads just like a transistor, and some transistors carry a built-in diode or resistor. The datasheet says which.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
TVS or ESD protection diode
Diode range, from the protected line to ground, part lifted if you can.
Working, it reads
A one-way part reads about 0.6 to 0.8 V forward and open in reverse. A two-way part reads open both ways. Arrays with several lines read as the datasheet's diagram draws them.
Dead, it reads
- From the line to ground, the same reading both ways, near 0 V with a continuous beep: shorted.
- A reading both ways on a one-way part: leaky.
- A one-way part open both ways: failed open.
- On the board
- , a line reading shorted to ground can be this part or anything else on that line. Lift it: if the short goes with it, it has failed.
- Compare:
- The same part on the next line or connector pin is the healthy reading to compare with.
- Watch for:
- A two-way part reads open both ways when it is good, exactly like one that has failed open. The meter cannot tell them apart; an identical part on the next line can.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
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.
Schottky diode
Diode range, part lifted or one leg off the pad. Red probe on the anode.
Working, it reads
About 0.15 to 0.45 V anode to cathode, roughly half a silicon diode, and open the other way.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- A reading the wrong way round as well: leaky.
- Open both ways: failed open.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A large Schottky can read about 0.1 V forward and beep like a short, and leaks a little the wrong way when good, more when warm. It is shorted only if it reads the same both ways. Measure it cold, beside an identical cold one.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
Printed with a code easy to misread as AC
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 AC
For a marking with its end worn or burnt off. Each code has a page of its own.
Codes not listed here are printed on 49 more parts.
Open this in the search to correct a character or try another package.