SMD code 100
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.
100 on a chip resistor
10 Ω
10 Ω resistor, 5%
10 followed by 0 zeros. Three digits is normally the 5% series. The same marking also reads as 10 pF on a capacitor or 10 µH on an inductor, and nothing in the code says which; the body of the part does.
The same characters on another part
- 10 pF capacitor
- 10 µH inductor
Check it with a meter
Lift one end and measure across it. A good one reads 10 Ω within 5%. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 10 Ω on the board is a fault. Open, or well above 10 Ω, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 10 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 (SOT-23-5, SOT-23, SMA), 100 is a part code instead. Those parts are listed below.
Not sure which one you have?
Answer up to 4 quick questions and these 6 parts are ranked, with a meter test that settles it. It works on a dead part too.
The only part printed 100 in our tables
SML4764
- What it is
- Zener diode
- Maker
- Vishay
- Package
- SMA
- Pins
- 2
- Details
- 100 V Zener diode
- Source
- From the manufacturer's datasheet
Is it dead?
Diode range for the forward check, part lifted, red probe on the anode. A bench supply for the Zener voltage.
Working, it reads
About 0.6 to 0.8 V forward and open in reverse on the diode range. Its Zener voltage shows only on a supply: feed it through a resistor that sets about 5 mA, cathode to positive, read quickly, and it should hold near its rated voltage.
Dead, it reads
- The same reading both ways round, near 0 V with a continuous beep or the same middling value: shorted.
- Open both ways, forward too: failed open.
- Holds well off its rated voltage on the supply test: drifted.
- A soft knee, or a voltage that creeps on the supply test: 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 meter's diode range stops at about 2 to 3 V, so almost every Zener reads open in reverse on it, good or bad; a 3 V meter may just show a 2.4 or 2.7 V part. Above about 3 V the meter cannot tell a Zener from a plain diode.
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 100
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 100
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.