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SMD code HX

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.

3 parts are printed HX

Not sure which one you have?

Answer up to 4 quick questions and these 3 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • MMBTRC104SSSOT-23Digital transistor (resistors built in), 3 pins, Diotec
    What it is
    Digital transistor (resistors built in)
    Maker
    Diotec
    Package
    SOT-23
    Pins
    3
    Details
    SMD Digital NPN Transistors
    Source
    From the manufacturer's datasheet

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

    Datasheetfor MMBTRC104SS, opens in a new tab
  • SN74AUP1G80DRYSONFlip-flop, 6 pins, Texas Instruments
    What it is
    Flip-flop
    Maker
    Texas Instruments
    Package
    SON
    Pins
    6
    Details
    Low-Power Single Positive-Edge-Triggered D-Type Flip-Flop
    Source
    From the manufacturer's datasheet

    Is it dead? The meter test is below: Integrated circuit.

    Datasheetfor SN74AUP1G80DRY, opens in a new tab
  • SN74AUP1G80DSFSONFlip-flop, 6 pins, Texas Instruments
    What it is
    Flip-flop
    Maker
    Texas Instruments
    Package
    SON
    Pins
    6
    Details
    Low-Power Single Positive-Edge-Triggered D-Type Flip-Flop
    Source
    From the manufacturer's datasheet

    Is it dead? The meter test is below: Integrated circuit.

    Datasheetfor SN74AUP1G80DSF, opens in a new tab

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.

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.

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.

Codes that begin with HX

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

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