SMD code UM-
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 and published code lists.
80 parts are printed UM-
Not sure which one you have?
Answer up to 4 quick questions and these 50 parts are ranked, with a meter test that settles it. It works on a dead part too.
TPS3897PDRYSONVoltage supervisor, 6 pins, Texas InstrumentsVoltage supervisorSON6 pinsTexas Instruments
- What it is
- Voltage supervisor
- Maker
- Texas Instruments
- Package
- SON
- Pins
- 6
- Details
- Single-Channel, Adjustable Voltage Monitor in Ultra-Small Package
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Integrated circuit.
WS05DUCFMSOD-882ESD protection diode, 2 pins, WayonESD protection diodeSOD-8822 pinsWayon
- What it is
- ESD protection diode
- Maker
- Wayon
- Package
- SOD-882
- Pins
- 2
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
PSMAJ440CA-13SMATVS diode, 2 pins, HXYTVS diodeSMA2 pinsHXY
- What it is
- TVS diode
- Maker
- HXY
- Package
- SMA
- Pins
- 2
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
SMAJ440CA/TR13SMATVS diode, 2 pins, HXYTVS diodeSMA2 pinsHXY
- What it is
- TVS diode
- Maker
- HXY
- Package
- SMA
- Pins
- 2
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
WS05DUCMFHSOD-882ESD protection diode, 2 pins, WayonESD protection diodeSOD-8822 pinsWayon
- What it is
- ESD protection diode
- Maker
- Wayon
- Package
- SOD-882
- Pins
- 2
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
WS2012KFSOD-882ESD protection diode, 2 pins, WayonESD protection diodeSOD-8822 pinsWayon
- What it is
- ESD protection diode
- Maker
- Wayon
- Package
- SOD-882
- Pins
- 2
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
2SC3618-MSOT-893 pins, NEC ElectronicsNot recordedSOT-893 pinsNEC Electronics
- What it is
- Not recorded
- Maker
- NEC Electronics
- Package
- SOT-89
- Pins
- 3
- Details
- Si-npn: AF-Amp, Sw, 25V, 1A, 2W, 250MHz, B=900..1600
- Source
- Published code list
Is it dead? The meter test is below: This part.
2SC3618UMSOT-893 pins, RenesasNot recordedSOT-893 pinsRenesas
- What it is
- Not recorded
- Maker
- Renesas
- Package
- SOT-89
- Pins
- 3
- Source
- Published code list
Is it dead? The meter test is below: This part.
74LVC1G06SESOT-3535 pins, Diodes IncorporatedNot recordedSOT-3535 pinsDiodes Incorporated
- What it is
- Not recorded
- Maker
- Diodes Incorporated
- Package
- SOT-353
- Pins
- 5
- Details
- CMOS logic IC: Inverter (ODO)
- Source
- Published code list
Is it dead? The meter test is below: Integrated circuit.
74LVC1G06W5SOT-23-55 pins, Diodes IncorporatedNot recordedSOT-23-55 pinsDiodes Incorporated
- What it is
- Not recorded
- Maker
- Diodes Incorporated
- Package
- SOT-23-5
- Pins
- 5
- Details
- CMOS logic IC: Inverter (ODO)
- Source
- Published code list
Is it dead? The meter test is below: Integrated circuit.
74LVC1G06ZSOT-5535 pins, Diodes IncorporatedNot recordedSOT-5535 pinsDiodes Incorporated
- What it is
- Not recorded
- Maker
- Diodes Incorporated
- Package
- SOT-553
- Pins
- 5
- Details
- CMOS logic IC: Inverter (ODO)
- Source
- Published code list
Is it dead? The meter test is below: Integrated circuit.
4 more parts have no package on record
TSD023-729WSSchottky diode, Taitron ComponentsSchottky diodeNot recordedNot recordedTaitron Components
- What it is
- Schottky diode
- Maker
- Taitron Components
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Schottky Barrier Diodes (Two Terminals)
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
XBP4SMAJ015C-GESD protection diode, Torex SemiconductorESD protection diodeNot recordedNot recordedTorex Semiconductor
- What it is
- ESD protection diode
- Maker
- Torex Semiconductor
- Package
- Not recorded
- Pins
- Not recorded
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
74LVC1G06FW4Diodes IncorporatedNot recordedNot recordedNot recordedDiodes Incorporated
- What it is
- Not recorded
- Maker
- Diodes Incorporated
- Package
- Not recorded
- Pins
- Not recorded
- Details
- CMOS logic IC: Inverter (ODO)
- Source
- Published code list
Is it dead? The meter test is below: Integrated circuit.
74LVC1G06FZ4Diodes IncorporatedNot recordedNot recordedNot recordedDiodes Incorporated
- What it is
- Not recorded
- Maker
- Diodes Incorporated
- Package
- Not recorded
- Pins
- Not recorded
- Details
- CMOS logic IC: Inverter (ODO)
- Source
- Published code list
Is it dead? The meter test is below: Integrated circuit.
Is it dead? One meter test per kind
Parts of the same kind are tested the same way, so each test is here once. Each part above points to its own.
Integrated circuit
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.
Schottky diode
Diode range, part lifted or one leg off the pad. Red probe on the anode.
Working, it reads
About 0.15 to 0.45 V anode to cathode, roughly half a silicon diode, and open the other way.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- A reading the wrong way round as well: leaky.
- Open both ways: failed open.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- A large Schottky can read about 0.1 V forward and beep like a short, and leaks a little the wrong way when good, more when warm. It is shorted only if it reads the same both ways. Measure it cold, beside an identical cold one.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
TVS or ESD protection diode
Diode range, from the protected line to ground, part lifted if you can.
Working, it reads
A one-way part reads about 0.6 to 0.8 V forward and open in reverse. A two-way part reads open both ways. Arrays with several lines read as the datasheet's diagram draws them.
Dead, it reads
- From the line to ground, the same reading both ways, near 0 V with a continuous beep: shorted.
- A reading both ways on a one-way part: leaky.
- A one-way part open both ways: failed open.
- On the board
- , a line reading shorted to ground can be this part or anything else on that line. Lift it: if the short goes with it, it has failed.
- Compare:
- The same part on the next line or connector pin is the healthy reading to compare with.
- Watch for:
- A two-way part reads open both ways when it is good, exactly like one that has failed open. The meter cannot tell them apart; an identical part on the next line can.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
This part
Diode range and ohms range, part lifted.
Working, it reads
Depends on what it is. The datasheet, or an identical part, says.
Dead, it reads
- Between two pins, the same reading both ways, near 0 V with a continuous beep: shorted.
- Open between every pair of pins: failed open, or a part that reads open when working.
- 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.
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?
Open this in the search to correct a character or try another package.