SMD code 34-
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.
83 parts are printed 34-
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.
RB160LAM-40SOD-128Schottky diode, 2 pins, ROHMSchottky diodeSOD-1282 pinsROHM
- What it is
- Schottky diode
- Maker
- ROHM
- Package
- SOD-128
- Pins
- 2
- Details
- Schottky Barrier Diode
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
RB160LAM-40TFSOD-128Schottky diode, 2 pins, ROHMSchottky diodeSOD-1282 pinsROHM
- What it is
- Schottky diode
- Maker
- ROHM
- Package
- SOD-128
- Pins
- 2
- Details
- Schottky Barrier Diode (AEC-Q101 qualified)
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
RB162MM-40SOD-123FSchottky diode, 2 pins, ROHMSchottky diodeSOD-123F2 pinsROHM
- What it is
- Schottky diode
- Maker
- ROHM
- Package
- SOD-123F
- Pins
- 2
- Details
- Schottky Barrier Diode
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
RB162MM-40TFSOD-123FSchottky diode, 2 pins, ROHMSchottky diodeSOD-123F2 pinsROHM
- What it is
- Schottky diode
- Maker
- ROHM
- Package
- SOD-123F
- Pins
- 2
- Details
- Schottky Barrier Diode (AEC-Q101 qualified)
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
RB531SM-40SOD-523Schottky diode, 2 pins, ROHMSchottky diodeSOD-5232 pinsROHM
- What it is
- Schottky diode
- Maker
- ROHM
- Package
- SOD-523
- Pins
- 2
- Details
- Schottky Barrier Diode
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
S-LMBR340FT1GSOD-123FSchottky diode, 2 pins, LRCSchottky diodeSOD-123F2 pinsLRC
- What it is
- Schottky diode
- Maker
- LRC
- Package
- SOD-123F
- Pins
- 2
- Details
- Schottky diode, VR 40 V, IF 3 A, VF Max 0.5 V
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
S-LMUN5334DW1T1GSOT-363Digital transistor (resistors built in), 6 pins, LRCDigital transistor (resistors built in)SOT-3636 pinsLRC
- What it is
- Digital transistor (resistors built in)
- Maker
- LRC
- Package
- SOT-363
- Pins
- 6
- Details
- Digital transistor (bias resistors built in), P+N, IC 100 mA, VCEO 50 V
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Digital transistor.
SMUN5334DWSOT-363Digital transistor (resistors built in), 6 pins, SeCoSDigital transistor (resistors built in)SOT-3636 pinsSeCoS
- What it is
- Digital transistor (resistors built in)
- Maker
- SeCoS
- Package
- SOT-363
- Pins
- 6
- Details
- Digital (resistor-equipped) transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Digital transistor.
SWJ3134K-CSOT-883MOSFET, 3 pins, SeCoSMOSFETSOT-8833 pinsSeCoS
- What it is
- MOSFET
- Maker
- SeCoS
- Package
- SOT-883
- Pins
- 3
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: MOSFET.
TUNM2NSOT-363Digital transistor (resistors built in), 6 pins, Galaxy MicroelectronicsDigital transistor (resistors built in)SOT-3636 pinsGalaxy Microelectronics
- What it is
- Digital transistor (resistors built in)
- Maker
- Galaxy Microelectronics
- Package
- SOT-363
- Pins
- 6
- Details
- 50V, 100mA, NPN Bipolar Digital Transistor 50V, 100mA, PNP Bipolar Digital Transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Digital transistor.
UNM2NSOT-363Digital transistor (resistors built in), 6 pins, Galaxy MicroelectronicsDigital transistor (resistors built in)SOT-3636 pinsGalaxy Microelectronics
- What it is
- Digital transistor (resistors built in)
- Maker
- Galaxy Microelectronics
- Package
- SOT-363
- Pins
- 6
- Details
- 50V, 100mA, NPN Bipolar Digital Transistor 50V, 100mA, PNP Bipolar Digital Transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Digital transistor.
4 more parts have no package on record
RESD3V3UCEDESD protection diode, ROHMESD protection diodeNot recordedNot recordedROHM
- What it is
- ESD protection diode
- Maker
- ROHM
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Ultra-Low Capacitance ESD Protection Diode / TVS
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: TVS or ESD protection diode.
SGM2571CDYGLoad switch, 4 pins, SG MicroLoad switchNot recorded4 pinsSG Micro
- What it is
- Load switch
- Maker
- SG Micro
- Package
- Not recorded
- Pins
- 4
- Details
- 5.5V, 1A, 34mΩ RON Load Switch with Reverse Current Protection
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Load switch.
SM340HTSchottky diode, SeCoSSchottky diodeNot recordedNot recordedSeCoS
- What it is
- Schottky diode
- Maker
- SeCoS
- Package
- Not recorded
- Pins
- Not recorded
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
VSKY024063Schottky diode, VishaySchottky diodeNot recordedNot recordedVishay
- What it is
- Schottky diode
- Maker
- Vishay
- Package
- Not recorded
- Pins
- Not recorded
- Details
- Small Signal Schottky Diode FlipKY Gen 3
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: Schottky diode.
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.
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.
Digital transistor
Ohms range, part lifted. The datasheet gives the built-in resistors: R1 in series with the base, R2 from base to emitter.
Working, it reads
Base to emitter reads about R1 plus R2 either way round, about 20 kΩ on a 10 k and 10 k part, give or take their wide tolerance. Collector to emitter reads open. A part with no R2 reads a junction behind R1 one way instead.
Dead, it reads
- Collector to emitter the same both ways, near 0 Ω with a continuous beep: shorted.
- From the base, open or far above R1 plus R2: R1 has failed. Static damage shows here most often.
- Base to emitter near 0 Ω: failed short.
- 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:
- The readings depend on the resistor values, so an identical part elsewhere on the board is the surest reference. Measure it the same way.
- Watch for:
- On the diode range a good part with 10 kΩ resistors reads open on every pair, so a good part looks dead there. Use the ohms range.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
Load switch
Voltage, board powered, black probe on ground.
Working, it reads
Switched on, the output pin sits at the input voltage. Switched off, it sits near 0 V.
Dead, it reads
- Output at the input voltage while switched off: the pass element has shorted.
- Input present and switched on, no output: failed open, or shut down into a shorted load. Power off and measure output to ground.
- On the board:
- An output near 0 Ω to ground is usually the load. Lift the output pin to see which.
- 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 pinout and whether the enable is active high or low differ between parts. The datasheet gives both.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
MOSFET
Diode range, part lifted. Test drain to source first, then short gate to source and test again.
Working, it reads
One way between drain and source reads about 0.4 to 0.9 V, the body diode, and the other way open. The gate reads open to both other pins.
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.
- No body diode at all: failed open.
- On the board
- the gate usually has a resistor to the source, which reads as that resistor and is not a fault. 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.
Did you find your part?
Open this in the search to correct a character or try another package.