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FMMT491A, in 3D

FMMT491A

Diodes Incorporated

40V, 1A, NPN Medium Power Transistor

Extended
DatasheetJLCPCBLCSCdiodes/FMMT491A
Category
Bipolar (BJT)
Package
SOT-23
Pins
3

Overview

The FMMT491A is a bipolar made by Diodes Incorporated in a SOT-23 package with 3 pins. 40V, 1A, NPN Medium Power Transistor.

PCBKit's library has its KiCad symbol (Transistors:NPN B1 E2 C3, from CERN's library) and its footprint (Package_TO_SOT_SMD:SOT-23, from KiCad's library), ready for a KiCad board. JLCPCB lists it (part C5248999). 4 open-source boards in 2 repositories on GitHub use it.

Symbol

Transistors:NPN B1 E2 C3From CERN's library

Footprint

123
Package_TO_SOT_SMD:SOT-23From KiCad's library

Parameters

11
Collector - Emitter Voltage VCEO
40V
Current - Collector Cutoff
100nA
Current - Collector(Ic)
1A
DC Current Gain
900
Emitter-Base Voltage(Vebo)
7V
Number
1 NPN
Operating Temperature
-55℃~+150℃
Pd - Power Dissipation
500mW
Transition frequency(fT)
150MHz
Vce Saturation(VCE(sat))
500mV；300mV
type
NPN

Order codes

1

Pinout

3
The pins of the FMMT491A
PinNameType
1BPassive
2EPassive
3CPassive

Open-source boards using it

All 4
  • 2 layers61.4 × 19.6 mmTurnSignal, the printed circuit board in 3D

    TurnSignal

    YingK8/Turn-Signal

    27 partsCC0-1.0
  • 2 layersWith humiditier, the printed circuit board in 3D

    With humiditier

    YingK8/ESP32-BLE-Macro-Pad

    A compact, programmable macropad with Bluetooth connectivity, featuring 6 mechanical keys and a rotary encoder for media control.

    43 parts

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Questions

Is there a KiCad symbol and footprint for the FMMT491A?

Yes. The symbol is Transistors:NPN B1 E2 C3 and the footprint Package_TO_SOT_SMD:SOT-23, both drawn on this page. PCBKit places them on a board for you when you design with it.

What package is the FMMT491A?

SOT-23, with 3 pins. Its footprint is drawn on this page.

Where is the FMMT491A datasheet?

Diodes Incorporated publishes it: the Datasheet link on this page opens it.

Where can I order the FMMT491A?

JLCPCB lists it as part C5248999, with 0 in stock; the sellers' links on this page open their listings.

What can replace the FMMT491A?

Parts like it in the library: the 8550M-D by Foshan Blue Rocket Elec, the SS8550 by MSKSEMI, the PBSS4160T by Nexperia and the S8550 2TY-TD(0.35) by TDSEMIC. Check their datasheets: a part that fits the footprint may still differ in its ratings.

Which open-source boards use the FMMT491A?

4 boards in 2 repositories on GitHub; the most starred are listed on this page, with their KiCad files.

Parts like it

8