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SMD code 64s

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.

64s on a chip resistor

45.3 Ω

45.3 Ω resistor, 1%

EIA-96 precision code: 64 selects 4.53 from the E96 series and S multiplies by 10. These are 1% parts. The trailing S is also used as a decimal point, so this could instead be 64 Ω. Measure it before fitting a replacement. If it has failed and reads open or high, that settles nothing: measure the same position on a working board.

Check it with a meter

Lift one end and measure across it. A good one reads 45.3 Ω within 1%. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 45.3 Ω on the board is a fault. Open, or well above 45.3 Ω, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 45.3 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, SOT-23-5, SMA), 64s is a part code instead. Those parts are listed below.

7 parts are printed 64s

Not sure which one you have?

Answer up to 4 quick questions and these 7 parts are ranked, with a meter test that settles it. It works on a dead part too.

  • FSB025C40S-T23-HSOT-23Schottky diode, 3 pins, Formosa MicrosemiSchottky diodeSOT-233 pinsFormosa Microsemi
    What it is
    Schottky diode
    Maker
    Formosa Microsemi
    Package
    SOT-23
    Pins
    3
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: Schottky diode.

  • FSB025C40S-T23-Q1-HSOT-23Schottky diode, 3 pins, Formosa MicrosemiSchottky diodeSOT-233 pinsFormosa Microsemi
    What it is
    Schottky diode
    Maker
    Formosa Microsemi
    Package
    SOT-23
    Pins
    3
    Source
    Manufacturer datasheet

    Is it dead? The meter test is below: Schottky diode.

  • BAT64-04SOT-23Schottky diode, 3 pins, InfineonSchottky diodeSOT-233 pinsInfineon
    What it is
    Schottky diode
    Maker
    Infineon
    Package
    SOT-23
    Pins
    3
    Details
    0.25A, 40V, Surface Mount Small Signal Schottky Diodes
    Source
    Published code list

    Is it dead? The meter test is below: Schottky diode.

  • BAT64-04WSOT-323Schottky diode, 3 pins, InfineonSchottky diodeSOT-3233 pinsInfineon
    What it is
    Schottky diode
    Maker
    Infineon
    Package
    SOT-323
    Pins
    3
    Details
    0.25A, 40V, Surface Mount Small Signal Schottky Diodes
    Source
    Published code list

    Is it dead? The meter test is below: Schottky diode.

  • MMBZ5264SPTSOT-23Zener diode, 3 pins, Chenmko EnterpriseZener diodeSOT-233 pinsChenmko Enterprise
    What it is
    Zener diode
    Maker
    Chenmko Enterprise
    Package
    SOT-23
    Pins
    3
    Details
    Zener diode: 58.80..61.20V, Izt=2.1mA, Zzt=170 , 225mW
    Source
    Published code list

    Is it dead? The meter test is below: Zener diode.

  • MMCZ5264SPTSOT-23Zener diode, 3 pins, Chenmko EnterpriseZener diodeSOT-233 pinsChenmko Enterprise
    What it is
    Zener diode
    Maker
    Chenmko Enterprise
    Package
    SOT-23
    Pins
    3
    Details
    Zener diode: 58.80..61.20V, Izt=2.1mA, Zzt=170 , 225mW
    Source
    Published code list

    Is it dead? The meter test is below: Zener diode.

  • MMHZ5264SPTSOD-123Zener diode, 2 pins, Chenmko EnterpriseZener diodeSOD-1232 pinsChenmko Enterprise
    What it is
    Zener diode
    Maker
    Chenmko Enterprise
    Package
    SOD-123
    Pins
    2
    Details
    Zener diode: 58.80..61.20V, Izt=2.1mA, Zzt=170, 225mW
    Source
    Published code list

    Is it dead? The meter test is below: Zener 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.

Zener diode

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 64s

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.