SMD code 1545
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 and published code lists.
1545 on a chip resistor
15.4 MΩ
15.4 MΩ resistor, 1%
154 followed by 5 zeros. Four digits is normally the 1% series.
Check it with a meter
Lift one end and measure across it. A good one reads 15.4 MΩ within 1%. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 15.4 MΩ on the board is a fault. Open, or well above 15.4 MΩ, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 15.4 MΩ. 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, SOT-23-5, SOT-89), 1545 is a part code instead. Those parts are listed below.
6 parts are printed 1545
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.
BL1545SOT-23NPN transistor, 3 pins, Galaxy MicroelectronicsNPN transistorSOT-233 pinsGalaxy Microelectronics
- What it is
- NPN transistor
- Maker
- Galaxy Microelectronics
- Package
- SOT-23
- Pins
- 3
- Details
- 420V, 0.5A, Medium Power NPN Bipolar Transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: NPN transistor.
BL1545ESOT-89NPN transistor, 3 pins, Galaxy MicroelectronicsNPN transistorSOT-893 pinsGalaxy Microelectronics
- What it is
- NPN transistor
- Maker
- Galaxy Microelectronics
- Package
- SOT-89
- Pins
- 3
- Details
- 420V, 0.5A, Medium Power NPN Bipolar Transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: NPN transistor.
BL1545RSOT-223NPN transistor, 4 pins, Galaxy MicroelectronicsNPN transistorSOT-2234 pinsGalaxy Microelectronics
- What it is
- NPN transistor
- Maker
- Galaxy Microelectronics
- Package
- SOT-223
- Pins
- 4
- Details
- 420V, 0.5A, Medium Power NPN Bipolar Transistor
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: NPN transistor.
GSBL1545SOT-23NPN transistor, 3 pins, Good-ArkNPN transistorSOT-233 pinsGood-Ark
- What it is
- NPN transistor
- Maker
- Good-Ark
- Package
- SOT-23
- Pins
- 3
- Details
- NPN transistor, 420 V, 0.5 A
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: NPN transistor.
2 more parts have no package on record
PMA3-15453+RF amplifier (MMIC), Mini-CircuitsRF amplifier (MMIC)Not recordedNot recordedMini-Circuits
- What it is
- RF amplifier (MMIC)
- Maker
- Mini-Circuits
- Package
- Not recorded
- Pins
- Not recorded
- Details
- MMIC amplifier, 15-45 GHz
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: RF amplifier.
PMA3-24323LN+RF amplifier (MMIC), Mini-CircuitsRF amplifier (MMIC)Not recordedNot recordedMini-Circuits
- What it is
- RF amplifier (MMIC)
- Maker
- Mini-Circuits
- Package
- Not recorded
- Pins
- Not recorded
- Details
- MMIC amplifier, 24-32 GHz
- Source
- Manufacturer datasheet
Is it dead? The meter test is below: RF amplifier.
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.
NPN transistor
Diode range, part lifted or its base leg off the pad.
Working, it reads
Red probe on the base 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.
RF amplifier
Voltage, board powered, on the output pin that the bias resistor or choke feeds.
Working, it reads
The output pin sits at the device voltage the datasheet gives, a few volts, below the supply.
Dead, it reads
- Output pin at 0 V, or near 0 Ω to ground with the power off: shorted inside.
- Output pin at the full supply voltage: open inside, no current flowing.
- On the board:
- Measured on the board with power on; the bias network is part of the reading.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
- Watch for:
- The figures depend on the part and its bias resistor. The datasheet gives both.
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 1545
One character differs, and it is one that is easy to confuse under a lamp. Each code has a page of its own.
Did you find your part?
Open this in the search to correct a character or try another package.