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SMD code 111

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.

111 on a chip resistor

110 Ω

110 Ω resistor, 5%

11 followed by 1 zero. Three digits is normally the 5% series. The same marking also reads as 110 pF on a capacitor or 110 µH on an inductor, and nothing in the code says which; the body of the part does.

The same characters on another part

  • 110 pF capacitor
  • 110 µH inductor

Check it with a meter

Lift one end and measure across it. A good one reads 110 Ω within 5%. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 110 Ω on the board is a fault. Open, or well above 110 Ω, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 110 Ω. A burnt resistor usually means the part it feeds drew too much, so find that before fitting a new one.

On a transistor or diode body (WSON, SOT-323, SOT-23), 111 is a part code instead. Those parts are listed below.

2 parts are printed 111

Not sure which one you have?

Answer up to 4 quick questions and these 2 parts are ranked, with a meter test that settles it. It works on a dead part too.

Digital transistor (PNP, resistors built in), all SOT-323, 3 pins, all ROHM.

  • DTA113ZU3SOT-323
    What it is
    Digital transistor (PNP, resistors built in)
    Maker
    ROHM
    Package
    SOT-323
    Pins
    3
    Details
    PNP -50V, -100mA digital transistor (bias resistor built-in)
    Source
    From the manufacturer's datasheet

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

  • DTA113ZUBSOT-323
    What it is
    Digital transistor (PNP, resistors built in)
    Maker
    ROHM
    Package
    SOT-323
    Pins
    3
    Details
    PNP -50V, -100mA digital transistor (bias resistor built-in)
    Source
    From the manufacturer's datasheet

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

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.

Codes that begin with 111

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.