SMD marking

7Din 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.

2 parts are printed 7D

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.

ESD protection diode, all Nexperia. What differs:

PESD15VS2UATSOT-233 pins3 pins
What it is
ESD protection diode
Maker
Nexperia
Package
SOT-23
Pins
3
Details
Double ESD protection diode in SOT23 package
Source
From the manufacturer's datasheet
Is it dead?
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:
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.
Datasheetfor PESD15VS2UAT, opens in a new tab
1 more part has no package on record. Nothing rules them out, so they stay.
- PESD20VV1BSF2 pins2 pins
  What it is
  ESD protection diode
  Maker
  Nexperia
  Package
  Not recorded
  Pins
  2
  Details
  Very low capacitance high voltage bidirectional ESD protection diode
  Source
  From the manufacturer's datasheet
  Is it dead?
  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:
  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.
  Datasheetfor PESD20VV1BSF, opens in a new tab

2 more parts are printed with a code easy to misread as 7D

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.

BZX84-B16printed 70SOT-23Zener diode, 3 pins, NexperiaZener diode3 pinsNexperia
Printed 70 on the part. Easy to misread as 7D. Check that character with a loupe before you order anything.
What it is
Zener diode
Maker
Nexperia
Package
SOT-23
Pins
3
Details
16 V ±2% voltage regulator (Zener) diode
Source
From the manufacturer's datasheet
Is it dead?
Diode range for the forward check, part lifted, red probe on the anode. A bench supply for the Zener voltage.
Working, it reads
About 0.6 to 0.8 V forward and open in reverse on the diode range. Its Zener voltage shows only on a supply: feed it through a resistor that sets about 5 mA, cathode to positive, read quickly, and it should hold near its rated voltage.
Dead, it reads
The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
Open both ways, forward too: failed open.
Holds well off its rated voltage on the supply test: drifted.
A soft knee, or a voltage that creeps on the supply test: leaky.
On the board:
On the board this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
Compare:
If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
Watch for:
A meter's diode range stops at about 2 to 3 V, so almost every Zener reads open in reverse on it, good or bad; a 3 V meter may just show a 2.4 or 2.7 V part. Above about 3 V the meter cannot tell a Zener from a plain diode.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
Datasheetfor BZX84-B16, opens in a new tab
1 more part has no package on record. Nothing rules them out, so they stay.
- TLV75532PDQNprinted TDLDO regulator, 4 pins, Texas InstrumentsLDO regulator4 pinsTexas Instruments
  Printed TD on the part. Easy to misread as 7D. Check that character with a loupe before you order anything.
  What it is
  LDO regulator
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  4
  Details
  500mA, Low-IQ, Small-Size, Low-Dropout Regulator
  Source
  From the manufacturer's datasheet
  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.
  Datasheetfor TLV75532PDQN, opens in a new tab

7 more parts have codes that begin with 7D

Codes that begin with 7D

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

2N7002printed 7002SOT-23N-channel MOSFET, 3 pins, JSCJN-channel MOSFET3 pinsJSCJ
Printed 7002. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
N-channel MOSFET
Maker
JSCJ
Package
SOT-23
Pins
3
Details
N-channel enhancement mode Field-Effect Transistor (FET), 60V, SOT-23
Source
From the manufacturer's datasheet
Is it dead?
Diode range, part lifted. Test drain to source first, then short gate to source and test again.
Working, it reads
Red probe on the source, black on the drain: about 0.4 to 0.9 V, the body diode. Open the other way. The gate reads open to both other pins, both ways.
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. Often all three pins end up shorted together.
No body diode at all: failed open.
On the board:
On the board the gate usually has a resistor to the source, so gate to source reads that resistor, which is not a fault. A drain short can be the load. 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.
Datasheetfor 2N7002, opens in a new tab
2N7002Aprinted 702SOT-23N-channel MOSFET, 3 pins, DiotecN-channel MOSFET3 pinsDiotec
Printed 702. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
What it is
N-channel MOSFET
Maker
Diotec
Package
SOT-23
Pins
3
Details
MOSFET, N-channel, 60 V, 0.45 A
Source
From the manufacturer's datasheet
Is it dead?
Diode range, part lifted. Test drain to source first, then short gate to source and test again.
Working, it reads
Red probe on the source, black on the drain: about 0.4 to 0.9 V, the body diode. Open the other way. The gate reads open to both other pins, both ways.
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. Often all three pins end up shorted together.
No body diode at all: failed open.
On the board:
On the board the gate usually has a resistor to the source, so gate to source reads that resistor, which is not a fault. A drain short can be the load. 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.
Datasheetfor 2N7002A, opens in a new tab
5 more parts have no package on record. Nothing rules them out, so they stay.
- TLV7012DDFprinted 7012Comparator, 8 pins, Texas InstrumentsComparator8 pinsTexas Instruments
  Printed 7012. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Comparator
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  8
  Details
  Small-Size, Low-Power, Low-Voltage Comparators
  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 TLV7012DDF, opens in a new tab
- TLV7022DDFprinted 7022Comparator, 8 pins, Texas InstrumentsComparator8 pinsTexas Instruments
  Printed 7022. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Comparator
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  8
  Details
  Small-Size, Low-Power, Low-Voltage Comparators
  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 TLV7022DDF, opens in a new tab
- TLV9042IDDFprinted T042Operational amplifier, 8 pins, Texas InstrumentsOperational amplifier8 pinsTexas Instruments
  Printed T042. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Operational amplifier
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  8
  Details
  1.2V Ultra Low Voltage, 10µA Micro-Power RRIO Amplifier for Power Conscious Applications
  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 TLV9042IDDF, opens in a new tab
- TLV9052IDDFprinted T052Operational amplifier, 8 pins, Texas InstrumentsOperational amplifier8 pinsTexas Instruments
  Printed T052. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Operational amplifier
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  8
  Details
  5MHz, 15V/µs High Slew-Rate, RRIO Op Amp
  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 TLV9052IDDF, opens in a new tab
- TLV9062IDDFprinted T062Operational amplifier, 8 pins, Texas InstrumentsOperational amplifier8 pinsTexas Instruments
  Printed T062. Only the start matches what you typed, so this fits only if the rest of the marking is worn off.
  What it is
  Operational amplifier
  Maker
  Texas Instruments
  Package
  Not recorded
  Pins
  8
  Details
  10MHz, RRIO, CMOS Operational Amplifiers for Cost-Sensitive Systems
  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 TLV9062IDDF, opens in a new tab

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

2 parts are printed 7D

Is it dead?

Is it dead?

Printed with a code easy to misread

Is it dead?

Is it dead?

Codes that begin with 7D

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?

Is it dead?