SMD code search: identify a part by its marking
2 parts are printed S034. 2 printed with a similar-looking code.
2 parts are printed S034
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.
LDO regulator, 5 pins, all Ricoh. What differs:
R1191H034BSOT-89-5SOT-89-5
- What it is
- LDO regulator
- Maker
- Ricoh
- Package
- SOT-89-5
- Pins
- 5
- Details
- Linear voltage regulator IC: LDO, 3.4V±1.5%, 300mA, +CE, ECO
- 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.
RP201Q342BSOT-23-5SOT-23-5
- What it is
- LDO regulator
- Maker
- Ricoh
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: LDO, 3.4V±1%, 150mA, +CE, ECO
- 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.
2 more parts are printed with a code easy to misread as S034
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.
LDO regulator, all Shanghai Natlinear Electronics. What differs:
LN5034MRprinted 5034SOT-23-55 pinsSOT-23-55 pins
Printed 5034 on the part. Easy to misread as S034. Check that character with a loupe before you order anything.
- What it is
- LDO regulator
- Maker
- Shanghai Natlinear Electronics
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: LDO, 3.4V±2%, 70mA
- 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.
LN5034PRprinted 5034SOT-893 pinsSOT-893 pins
Printed 5034 on the part. Easy to misread as S034. Check that character with a loupe before you order anything.
- What it is
- LDO regulator
- Maker
- Shanghai Natlinear Electronics
- Package
- SOT-89
- Pins
- 3
- Details
- Linear voltage regulator IC: LDO, 3.4V±2%, 70mA
- 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.
10 more parts have codes that begin with S034
Codes that begin with S034
For a marking with its end worn or burnt off. Each one shows its full printed code.
Voltage supervisor, all USP-6C, 6 pins, all Torex.
XC6103D340ERprinted 5D340USP-6C
Printed 5D340. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.0V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D341ERprinted 5D341USP-6C
Printed 5D341. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.1V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D342ERprinted 5D342USP-6C
Printed 5D342. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.2V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D343ERprinted 5D343USP-6C
Printed 5D343. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.3V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D344ERprinted 5D344USP-6C
Printed 5D344. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.4V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D345ERprinted 5D345USP-6C
Printed 5D345. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.5V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D346ERprinted 5D346USP-6C
Printed 5D346. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.6V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D347ERprinted 5D347USP-6C
Printed 5D347. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.7V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D348ERprinted 5D348USP-6C
Printed 5D348. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.8V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
XC6103D349ERprinted 5D349USP-6C
Printed 5D349. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- CMOS-IC: VDet 4.9V5%, Hst, -MR, Reset PPO, Wt=100ms, Rt=100ms
- 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.
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.
- 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.
Get the app
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