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SMD code NS

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.

2 parts are printed NS

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.

3 pins. What differs:

  • 2SCR544RSOT-23Transistor, Diotec
    What it is
    Transistor
    Maker
    Diotec
    Package
    SOT-23
    Pins
    3
    Details
    SMD High Current NPN Transistors
    Source
    From the manufacturer's datasheet

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

    Datasheetfor 2SCR544R, opens in a new tab
  • TLV70933PKSOT-89LDO regulator, Texas Instruments
    What it is
    LDO regulator
    Maker
    Texas Instruments
    Package
    SOT-89
    Pins
    3
    Details
    150mA, 30V, 3.2μA Quiescent Current, Low-Dropout Linear Regulator
    Source
    From the manufacturer's datasheet

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

    Datasheetfor TLV70933PK, 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.

Bipolar transistor

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

Working, it reads

From the base, one probe colour 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.

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.

Printed with a code easy to misread as NS

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 NS

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.