SMD code K45
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.
K45 on a chip resistor
450 Ω
450 Ω resistor
The K is both the decimal point and the multiplier: 450 Ω.
Check it with a meter
Lift one end and measure across it. A good one reads 450 Ω. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 450 Ω on the board is a fault. Open, or well above 450 Ω, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 450 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), K45 is a part code instead. Those parts are listed below.
The only part printed K45 in our tables
BAS40-05
- What it is
- Schottky diode
- Maker
- Diodes Incorporated
- Package
- SOT-23
- Pins
- 3
- Details
- 40 V surface-mount Schottky barrier diode, dual common anode
- Source
- From the manufacturer's datasheet
Is it dead?
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.
Open this in the search to correct a character or try another package.