SMD marking

RAin 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.

4 parts are printed RA

Not sure which one you have?

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

BAV23CASOT-23Switching diode, DiotecSwitching diodeDiotec
What it is
Switching diode
Maker
Diotec
Package
SOT-23
Pins
3
Details
SMD Small Signal Diodes
Source
From the manufacturer's datasheet
Is it dead?
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:
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.
Datasheetfor BAV23CA, opens in a new tab
MMBD3004CASOT-23Switching diode, Taiwan SemiconductorSwitching diodeTaiwan Semiconductor
What it is
Switching diode
Maker
Taiwan Semiconductor
Package
SOT-23
Pins
3
Source
From the manufacturer's datasheet
Is it dead?
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:
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.
Datasheetfor MMBD3004CA, opens in a new tab
2 more parts have no package on record. Nothing rules them out, so they stay.
- BA895Diode, InfineonDiodeInfineon
  What it is
  Diode
  Maker
  Infineon
  Package
  Not recorded
  Pins
  Not recorded
  Source
  From the manufacturer's datasheet
  Is it dead?
  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:
  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.
  Datasheetfor BA895, opens in a new tab
- BF772RF transistor, InfineonRF transistorInfineon
  What it is
  RF transistor
  Maker
  Infineon
  Package
  Not recorded
  Pins
  Not recorded
  Source
  From the manufacturer's datasheet
  Is it dead?
  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:
  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.
  Datasheetfor BF772, opens in a new tab

9 more parts have codes that begin with RA

Codes that begin with RA

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

LM4041CEM3-ADJprinted RACSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041CEM3-ADJ, opens in a new tab
LM4041CEM3X-ADJprinted RACSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041CEM3X-ADJ, opens in a new tab
LM4041CIM3-ADJprinted RACSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041CIM3-ADJ, opens in a new tab
LM4041CIM3X-ADJprinted RACSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAC. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041CIM3X-ADJ, opens in a new tab
LM4041DEM3-ADJprinted RADSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAD. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041DEM3-ADJ, opens in a new tab
LM4041DEM3X-ADJprinted RADSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAD. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041DEM3X-ADJ, opens in a new tab
LM4041DIM3-ADJprinted RADSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAD. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041DIM3-ADJ, opens in a new tab
LM4041DIM3X-ADJprinted RADSOT-23Voltage reference, Texas InstrumentsVoltage referenceTexas Instruments
Printed RAD. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
Voltage reference
Maker
Texas Instruments
Package
SOT-23
Pins
3
Details
Precision Micro Power Shunt Voltage Reference
Source
From the manufacturer's 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.
Datasheetfor LM4041DIM3X-ADJ, opens in a new tab
1 more part has no package on record. Nothing rules them out, so they stay.
- RS1ALHprinted RALRectifier, Taiwan SemiconductorRectifierTaiwan Semiconductor
  Printed RAL. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Rectifier
  Maker
  Taiwan Semiconductor
  Package
  Not recorded
  Pins
  Not recorded
  Source
  From the manufacturer's datasheet
  Is it dead?
  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:
  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.
  Datasheetfor RS1ALH, opens in a new tab

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

4 parts are printed RA

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Codes that begin with RA

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?