Skip to content

SMD code UH in SOT-723

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.

Not sure which one you have?

Answer up to 4 quick questions and these 31 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • 2SD2696SOT-723NPN transistor, 3 pins, ROHMNPN transistor3 pinsROHM
    What it is
    NPN transistor
    Maker
    ROHM
    Package
    SOT-723
    Pins
    3
    Details
    Low frequency transistor (for amplification)
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: NPN transistor.

  • 14 more parts have no package on record. Nothing rules them out, so they stay.
    • ACZRQC9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.1 V 0.125 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • ACZRUC9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.33 V 0.15 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • CZRFR9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.1 V 0.2 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • CZRQC9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.1 V 0.125 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • CZRU9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.1 V 0.15 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • CZRUR9V1B-HFZener diode, ComchipZener diodeNot recordedComchip
      What it is
      Zener diode
      Maker
      Comchip
      Package
      Not recorded
      Pins
      Not recorded
      Details
      9.1 V 0.15 mW zener diode
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Zener diode.

    • KDS4148USwitching diode, KECSwitching diodeNot recordedKEC
      What it is
      Switching diode
      Maker
      KEC
      Package
      Not recorded
      Pins
      Not recorded
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: Silicon diode.

    • LFCV-1552+RF filter, Mini-CircuitsRF filterNot recordedMini-Circuits
      What it is
      RF filter
      Maker
      Mini-Circuits
      Package
      Not recorded
      Pins
      Not recorded
      Details
      LTCC filter, DC-15500 MHz
      Source
      Manufacturer datasheet

      Is it dead? The meter test is below: This part.

    • 3SK260ToshibaNot recordedNot recordedToshiba
      What it is
      Not recorded
      Maker
      Toshiba
      Package
      Not recorded
      Pins
      Not recorded
      Details
      dg mosfet TV mixer, 3SK151
      Source
      Published code list

      Is it dead? The meter test is below: MOSFET.

    • AP7341D-22FS4-7LDO regulator, Diodes IncorporatedLDO regulatorNot recordedDiodes Incorporated
      What it is
      LDO regulator
      Maker
      Diodes Incorporated
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 2.2V±1%, 300mA, +CE, CL
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

    • APE8865U4-29LDO regulator, Advanced Power ElectronicsLDO regulatorNot recordedAdvanced Power Electronics
      What it is
      LDO regulator
      Maker
      Advanced Power Electronics
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 2.9±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

    • APE8865U4-30LDO regulator, Advanced Power ElectronicsLDO regulatorNot recordedAdvanced Power Electronics
      What it is
      LDO regulator
      Maker
      Advanced Power Electronics
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 3.0±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

    • AX6608-29SCLDO regulator, AXElite TechnologyLDO regulatorNot recordedAXElite Technology
      What it is
      LDO regulator
      Maker
      AXElite Technology
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 2.9V±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

    • AX6608-30SCLDO regulator, AXElite TechnologyLDO regulatorNot recordedAXElite Technology
      What it is
      LDO regulator
      Maker
      AXElite Technology
      Package
      Not recorded
      Pins
      Not recorded
      Details
      Linear voltage regulator IC: LDO, 3.0V±2%, 300mA, +CE
      Source
      Published code list

      Is it dead? The meter test is below: Voltage regulator.

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.

NPN transistor

Diode range, part lifted or its base leg off the pad.

Working, it reads

Red probe on the base reads about 0.6 to 0.75 V to the emitter and to the collector, and open the other way round. Collector to emitter reads open both ways.

Dead, it reads

  • Collector to emitter the same both ways, near 0 V with a continuous beep: shorted. The commonest failure.
  • The base the same both ways to another pin, near 0 V or a middling value: a shorted junction.
  • Only one junction reads, or none: a junction has failed open. It then looks like a diode.
  • A reading the wrong way round, where it should be open: 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 pair of diodes with a common pin reads just like a transistor, and some transistors carry a built-in diode or resistor. The datasheet says which.

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.

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.

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.

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.

Voltage regulator

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.

Codes that begin with UH

For a marking with its end worn or burnt off. Each code has a page of its own.

Did you find your part?

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