SMD code T4
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.
15 parts are printed T4
Not sure which one you have?
Answer up to 4 quick questions and these 15 parts are ranked, with a meter test that settles it. It works on a dead part too.
1N4148WSOD-123Switching diode, 2 pins, Diodes IncorporatedSwitching diodeSOD-1232 pinsDiodes Incorporated
- What it is
- Switching diode
- Maker
- Diodes Incorporated
- Package
- SOD-123
- Pins
- 2
- Pinout
- 1 cathode
- 2 anode
- Details
- Surface-mount fast switching diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148W-GSOD-123Switching diode, 2 pins, Taiwan SemiconductorSwitching diodeSOD-1232 pinsTaiwan Semiconductor
- What it is
- Switching diode
- Maker
- Taiwan Semiconductor
- Package
- SOD-123
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WGWSOD-123Switching diode, 2 pins, DiotecSwitching diodeSOD-1232 pinsDiotec
- What it is
- Switching diode
- Maker
- Diotec
- Package
- SOD-123
- Pins
- 2
- Details
- SMD Small Signal Switching Diodes
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WHSOD-123Switching diode, 2 pins, Taiwan SemiconductorSwitching diodeSOD-1232 pinsTaiwan Semiconductor
- What it is
- Switching diode
- Maker
- Taiwan Semiconductor
- Package
- SOD-123
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WSSOD-323Switching diode, 2 pins, Diodes IncorporatedSwitching diodeSOD-3232 pinsDiodes Incorporated
- What it is
- Switching diode
- Maker
- Diodes Incorporated
- Package
- SOD-323
- Pins
- 2
- Pinout
- 1 cathode
- 2 anode
- Details
- Surface-mount fast switching diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WS-GSOD-323Switching diode, 2 pins, Taiwan SemiconductorSwitching diodeSOD-3232 pinsTaiwan Semiconductor
- What it is
- Switching diode
- Maker
- Taiwan Semiconductor
- Package
- SOD-323
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WSHSOD-323Switching diode, 2 pins, Taiwan SemiconductorSwitching diodeSOD-3232 pinsTaiwan Semiconductor
- What it is
- Switching diode
- Maker
- Taiwan Semiconductor
- Package
- SOD-323
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WTSOD-523Switching diode, 2 pins, Diodes IncorporatedSwitching diodeSOD-5232 pinsDiodes Incorporated
- What it is
- Switching diode
- Maker
- Diodes Incorporated
- Package
- SOD-523
- Pins
- 2
- Pinout
- 1 cathode
- 2 anode
- Details
- Surface-mount fast switching diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
BAV16WSOD-123Switching diode, 2 pins, Diodes IncorporatedSwitching diodeSOD-1232 pinsDiodes Incorporated
- What it is
- Switching diode
- Maker
- Diodes Incorporated
- Package
- SOD-123
- Pins
- 2
- Pinout
- 1 cathode
- 2 anode
- Details
- Surface-mount fast switching diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
BAV16WSSOD-323Switching diode, 2 pins, Diodes IncorporatedSwitching diodeSOD-3232 pinsDiodes Incorporated
- What it is
- Switching diode
- Maker
- Diodes Incorporated
- Package
- SOD-323
- Pins
- 2
- Pinout
- 1 cathode
- 2 anode
- Details
- Surface-mount fast switching diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
BZX84-C2V7SOT-23Zener diode, 3 pins, NexperiaZener diodeSOT-233 pinsNexperia
- What it is
- Zener diode
- Maker
- Nexperia
- Package
- SOT-23
- Pins
- 3
- Pinout
- 1 anode
- 2 not connected
- 3 cathode
- Details
- 2.7 V approx. ±5% voltage regulator (Zener) diode
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Zener diode.
BZX384-C2V7SOD-323Zener diode, 2 pins, NexperiaZener diodeSOD-3232 pinsNexperia
- What it is
- Zener diode
- Maker
- Nexperia
- Package
- SOD-323
- Pins
- 2
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Zener diode.
MMBD6100WSOT-323Switching diode, 3 pins, PanjitSwitching diodeSOT-3233 pinsPanjit
- What it is
- Switching diode
- Maker
- Panjit
- Package
- SOT-323
- Pins
- 3
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
2 more parts have no package on record
1N4148WPSwitching diode, DiotecSwitching diodeNot recordedNot recordedDiotec
- What it is
- Switching diode
- Maker
- Diotec
- Package
- Not recorded
- Pins
- Not recorded
- Details
- SMD Small Signal Switching Diodes
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon diode.
1N4148WTHSwitching diode, Taiwan SemiconductorSwitching diodeNot recordedNot recordedTaiwan Semiconductor
- What it is
- Switching diode
- Maker
- Taiwan Semiconductor
- Package
- Not recorded
- Pins
- Not recorded
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Silicon 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.
Silicon diode
Diode range, part lifted or one leg off the pad. Red probe on the anode.
Working, it reads
About 0.5 to 0.8 V anode to cathode, and open the other way. Small switching diodes read about 0.6 to 0.7 V; large rectifiers can read a little lower.
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: failed open.
- A reading the wrong way round as well: leaky.
- 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 three-pin body can hold two diodes. With a common pin they read two junctions from that pin, just like a transistor; in series they read two drops end to end. Test each pair the datasheet names.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
Zener diode
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
- 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.
Printed with a code easy to misread as T4
One character differs, and it is one that is easy to confuse under a lamp. Each code has a page of its own.
Codes that begin with T4
For a marking with its end worn or burnt off. Each code has a page of its own.
- T4S2
- T4BG1
- T4B31
- T4AG1
- T4A31
- T4DJ1
- T4D31
- T4F31
- T4H31
- T4CG1
- T4CS1
- T4IG1
- T4IS1
- T4QS1
- T41S1
- T42G1
- T481
- T401
- T411
- T442
- T431
- T421
- T451
- T462
- T491
Codes not listed here are printed on 30 more parts.
Open this in the search to correct a character or try another package.