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SMD code II

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.

Not sure which one you have?

Answer up to 4 quick questions and these 16 parts are ranked, with a meter test that settles it. It works on a dead part too.

The only part printed II in our tables

BBY51-02L

What it is
Not recorded
Maker
Infineon
Package
Not recorded
Pins
Not recorded
Source
From the manufacturer's datasheet

Is it dead?

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.

Printed with a code easy to misread as II

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 II

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 28 more parts.

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