SMD code search: identify a part by its marking
10 parts are printed FST. 22 printed with a similar-looking code.
10 parts are printed FST
Not sure which one you have?
Answer up to 4 quick questions and these 10 parts are ranked, with a meter test that settles it. It works on a dead part too.
IXD4901D631ER-GUSP-6C6 pins, IXYSNot recordedUSP-6C6 pinsIXYS
- What it is
- Not recorded
- Maker
- IXYS
- Package
- USP-6C
- Pins
- 6
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
IXD4901D631MR-GSOT-23-55 pins, IXYSNot recordedSOT-23-55 pinsIXYS
- What it is
- Not recorded
- Maker
- IXYS
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
IXD4901D631PR-GSOT-89-55 pins, IXYSNot recordedSOT-89-55 pinsIXYS
- What it is
- Not recorded
- Maker
- IXYS
- Package
- SOT-89-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
IXD5122A524MR-GSOT-23-5Voltage supervisor, 5 pins, IXYSVoltage supervisorSOT-23-55 pinsIXYS
- What it is
- Voltage supervisor
- Maker
- IXYS
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.4V±2%, -Reset ODO, +WDEN, PUR, W t=400ms, Rdt=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.
XC6122A524MR-GSOT-23-5Voltage supervisor, 5 pins, TorexVoltage supervisorSOT-23-55 pinsTorex
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 2.4V±2%, -Reset ODO, +WDEN, PUR, W t=400ms, Rdt=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.
XC6901D631ER-GUSP-6C6 pins, TorexNot recordedUSP-6C6 pinsTorex
- What it is
- Not recorded
- Maker
- Torex
- Package
- USP-6C
- Pins
- 6
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
XC6901D631MR-GSOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
XC6901D631PR-GSOT-89-55 pins, TorexNot recordedSOT-89-55 pinsTorex
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-89-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -6.3V±1.5%, 200mA, +CE, 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.
2 more parts have no package on record
IXD5127C42E7RVoltage supervisor, IXYSVoltage supervisorNot recordedNot recordedIXYS
- What it is
- Voltage supervisor
- Maker
- IXYS
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Voltage detector IC: 4.2V±0.8%, -Reset PPO, -MR, Rdt=800ms
- 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.
XC6127C42E7RVoltage supervisor, TorexVoltage supervisorNot recordedNot recordedTorex
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Voltage detector IC: 4.2V±0.8%, -Reset PPO, -MR, Rdt=800ms
- 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.
22 more parts are printed with a code easy to misread as FST
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.
IXD4901D461ER-Gprinted FS7USP-6C6 pins, IXYSNot recordedUSP-6C6 pinsIXYS
Printed FS7 on the part. Easy to misread as FST. 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: -4.6V±1.5%, 200mA, +CE, 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.
IXD4901D461MR-Gprinted FS7SOT-23-55 pins, IXYSNot recordedSOT-23-55 pinsIXYS
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- IXYS
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -4.6V±1.5%, 200mA, +CE, 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.
IXD4901D461PR-Gprinted FS7SOT-89-55 pins, IXYSNot recordedSOT-89-55 pinsIXYS
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- IXYS
- Package
- SOT-89-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -4.6V±1.5%, 200mA, +CE, 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.
IXD5122A537MR-Gprinted FS7SOT-23-5Voltage supervisor, 5 pins, IXYSVoltage supervisorSOT-23-55 pinsIXYS
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- IXYS
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 3.7V±2%, -Reset ODO, +WDEN, PUR, W t=400ms, Rdt=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.
LN61FC5552Mprinted F57SOT-23Voltage supervisor, 3 pins, Shanghai Natlinear ElectronicsVoltage supervisorSOT-233 pinsShanghai Natlinear Electronics
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Shanghai Natlinear Electronics
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 5.5V±2%, +Reset PPO, Rdt=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.
LN61FC5552Pprinted F57SOT-89Voltage supervisor, 3 pins, Shanghai Natlinear ElectronicsVoltage supervisorSOT-893 pinsShanghai Natlinear Electronics
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Shanghai Natlinear Electronics
- Package
- SOT-89
- Pins
- 3
- Details
- Voltage detector IC: 5.5V±2%, +Reset PPO, 50ms Rt delay
- 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.
LN6203P252Fprinted F5TSOT-223LDO regulator, Infinewin Electron TechniqueLDO regulatorSOT-223Not recordedInfinewin Electron Technique
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- LDO regulator
- Maker
- Infinewin Electron Technique
- Package
- SOT-223
- Pins
- Not recorded
- Details
- Linear voltage regulator IC: LDO, 2.5V±2%, 400mA, OCL
- 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.
LN6203P252Mprinted F5TSOT-89LDO regulator, 3 pins, Infinewin Electron TechniqueLDO regulatorSOT-893 pinsInfinewin Electron Technique
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- LDO regulator
- Maker
- Infinewin Electron Technique
- Package
- SOT-89
- Pins
- 3
- Details
- Linear voltage regulator IC: LDO, 2.5V±2%, 400mA, OCL
- 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.
XC61FC5552Mprinted F57SOT-23Voltage supervisor, 3 pins, TorexVoltage supervisorSOT-233 pinsTorex
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- SOT-23
- Pins
- 3
- Details
- CMOS-IC: Voltage Detector 5,5V, Reset Push-pull output, 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.
XC61FC5552Pprinted F57SOT-89Voltage supervisor, 3 pins, TorexVoltage supervisorSOT-893 pinsTorex
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- SOT-89
- Pins
- 3
- Details
- CMOS-IC: Voltage Detector 5,5V, Reset Push-pull output, 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.
XC61HC5552MRprinted F57SOT-23Voltage supervisor, 3 pins, TorexVoltage supervisorSOT-233 pinsTorex
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- SOT-23
- Pins
- 3
- Details
- Voltage detector IC: 5.5V±2%, -Reset PPO, Rdt=1..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.
XC66DC5524Mprinted F5TSOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator with volatge detector: LDO, 2.4V±2%, 100mA, Vdet=5.5V±2%, +Reset PPO
- 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.
XC66DC5544Mprinted F5TSOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator with volatge detector: LDO, 4.4V±2%, 100mA, Vdet=5.5V±2%, +Reset PPO
- 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.
XC66DN5524Mprinted F5TSOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator with volatge detector: LDO, 2.4V±2%, 100mA, Vdet=5.5V±2%, +Reset ODO
- 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.
XC66DN5544Mprinted F5TSOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
Printed F5T on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator with volatge detector: LDO, 4.4V±2%, 100mA, Vdet=5.5V±2%, +Reset ODO
- 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.
XC6122A537MR-Gprinted FS7SOT-23-5Voltage supervisor, 5 pins, TorexVoltage supervisorSOT-23-55 pinsTorex
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Voltage supervisor
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Voltage detector IC: 3.7V±2%, -Reset ODO, +WDEN, PUR, W t=400ms, Rdt=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.
XC6367F572MRprinted F57SOT-23-5DC-DC converter, 5 pins, TorexDC-DC converterSOT-23-55 pinsTorex
Printed F57 on the part. Easy to misread as FST. 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 st-up, 5.7V±2.5%, 200mA, 180kHz, +CE, soft start
- 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.
XC6382B571Mprinted F57SOT-23DC-DC converter, 3 pins, TorexDC-DC converterSOT-233 pinsTorex
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- DC-DC converter
- Maker
- Torex
- Package
- SOT-23
- Pins
- 3
- Details
- DC/DC voltage converter IC: PFM st-up, 5.7V±2.5%, 400mA, 100kHz, ext. transis.
- 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.
XC6382B571Pprinted F57SOT-89DC-DC converter, 3 pins, TorexDC-DC converterSOT-893 pinsTorex
Printed F57 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- DC-DC converter
- Maker
- Torex
- Package
- SOT-89
- Pins
- 3
- Details
- DC/DC voltage converter IC: PFM st-up, 5.7V±2.5%, 400mA, 100kHz, ext. transis.
- 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.
XC6901D461ER-Gprinted FS7USP-6C6 pins, TorexNot recordedUSP-6C6 pinsTorex
Printed FS7 on the part. Easy to misread as FST. 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: -4.6V±1.5%, 200mA, +CE, 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.
XC6901D461MR-Gprinted FS7SOT-23-55 pins, TorexNot recordedSOT-23-55 pinsTorex
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-23-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -4.6V±1.5%, 200mA, +CE, 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.
XC6901D461PR-Gprinted FS7SOT-89-55 pins, TorexNot recordedSOT-89-55 pinsTorex
Printed FS7 on the part. Easy to misread as FST. Check that character with a loupe before you order anything.
- What it is
- Not recorded
- Maker
- Torex
- Package
- SOT-89-5
- Pins
- 5
- Details
- Linear voltage regulator IC: -4.6V±1.5%, 200mA, +CE, 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.
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
The same search on your phone, and a camera with a light, zoom and tap to focus for a marking you cannot read. Sign in with your email address to use the same account.
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