SMD code Q
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 Q
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.
1SS405SOD-523Schottky diode, 2 pins, DiotecSchottky diodeSOD-5232 pinsDiotec
- What it is
- Schottky diode
- Maker
- Diotec
- Package
- SOD-523
- Pins
- 2
- Details
- SMD Small Signal Schottky Diodes
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: Schottky diode.
1 more part has no package on record
PS160M-D32ESD protection diode, PanjitESD protection diodeNot recordedNot recordedPanjit
- What it is
- ESD protection diode
- Maker
- Panjit
- Package
- Not recorded
- Pins
- Not recorded
- Source
- From the manufacturer's datasheet
Is it dead? The meter test is below: TVS or ESD protection 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.
Schottky diode
Diode range, part lifted or one leg off the pad. Red probe on the anode.
Working, it reads
About 0.15 to 0.45 V anode to cathode, roughly half a silicon diode, and open the other way.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- A reading the wrong way round as well: leaky.
- Open both ways: failed open.
- 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 large Schottky can read about 0.1 V forward and beep like a short, and leaks a little the wrong way when good, more when warm. It is shorted only if it reads the same both ways. Measure it cold, beside an identical cold one.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
TVS or ESD protection diode
Diode range, from the protected line to ground, part lifted if you can.
Working, it reads
A one-way part reads about 0.6 to 0.8 V forward and open in reverse. A two-way part reads open both ways. Arrays with several lines read as the datasheet's diagram draws them.
Dead, it reads
- From the line to ground, the same reading both ways, near 0 V with a continuous beep: shorted.
- A reading both ways on a one-way part: leaky.
- A one-way part open both ways: failed open.
- On the board
- , a line reading shorted to ground can be this part or anything else on that line. Lift it: if the short goes with it, it has failed.
- Compare:
- The same part on the next line or connector pin is the healthy reading to compare with.
- Watch for:
- A two-way part reads open both ways when it is good, exactly like one that has failed open. The meter cannot tell them apart; an identical part on the next line can.
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 Q
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 Q
For a marking with its end worn or burnt off. Each code has a page of its own.
Codes not listed here are printed on 931 more parts.
Open this in the search to correct a character or try another package.