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FMMT491ATA

Public Made by Adom

by adom

Diodes Incorporated Bipolar (BJT), SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.

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3D Model

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Symbol & Footprint

Schematic Symbol

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PCB Footprint

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Datasheet

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Contents

README

markdown

FMMT491ATA

Diodes Incorporated · Bipolar (BJT) · SOT-23

FMMT491ATA from Diodes Incorporated, in a SOT-23. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 B input Base of the NPN transistor; base current is rated up to 200 mA (IB) and VEBO is 7 V.
2 E passive Emitter of the NPN transistor; VEBO to base is rated 7 V maximum.
3 C passive Collector of the NPN transistor; VCEO 40 V, VCBO 40 V, IC 1 A continuous and 2 A peak.

Key specifications

Parameter Value
Manufacturer Diodes Incorporated
Package SOT-23
Category Transistors/Thyristors
Pins 3

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Collector-Base Breakdown Voltage BVCBO 40 V IC = 100µA 4
Collector-Emitter Breakdown Voltage BVCEO 40 V IC = 10mA 4
Emitter-Base Breakdown Voltage BVEBO 7 V IE = 100µA 4
Collector Cutoff Current ICBO 100 nA VCB = 30V, VCES = 30V 4
Emitter Cutoff Current IEBO 100 nA VEB = 5V 4
Collector Emitter Cutoff Current ICES 100 nA VCE = 30V, VCES = 30V 4
Static Forward Current Transfer Ratio hFE 300 IC = 1mA, VCE = 5V 4
Static Forward Current Transfer Ratio hFE 300 900 IC = 500mA, VCE = 5V 4
Static Forward Current Transfer Ratio hFE 200 IC = 1A, VCE = 5V 4
Static Forward Current Transfer Ratio hFE 35 IC = 2A, VCE = 5V 4
Collector-Emitter Saturation Voltage VCE(sat) 0.3 V IC = 500mA, IB = 50mA 4
Collector-Emitter Saturation Voltage VCE(sat) 0.5 V IC = 1A, IB = 100mA 4
Base-Emitter Turn-On Voltage VBE(on) 1 V IC = 1A, VCE = 5V 4
Base-Emitter Saturation Voltage VBE(sat) 1.1 V IC = 1A, IB = 100mA 4
Output Capacitance Cobo 10 pF VCB = 10V, f = 1MHz 4
Transition Frequency fT 150 MHz VCE = 10V, IC = 50mA, f = 100MHz 4
Collector-Base Voltage VCBO 40 V 2
Collector-Emitter Voltage VCEO 40 V 2
Emitter-Base Voltage VEBO 7 V 2
Continuous Collector Current IC 1 A 2
Peak Pulse Current ICM 2 A 2
Base Current IB 200 mA 2
Power Dissipation PD 500 mW Note 6: surface mounted on 15mm x 15mm FR4 PCB, 1oz copper, still air, TA=+25°C 2
Operating and Storage Temperature Range TJ, TSTG -55 150 C 2
Electrostatic Discharge - Human Body Model ESD HBM 8000 V JEDEC class 3B, per JESD22-A114 2
Electrostatic Discharge - Machine Model ESD MM 400 V JEDEC class C, per JESD22-A115 2
Thermal Resistance, Junction to Ambient RJA 250 C/W Note 6: surface mounted on 15mm x 15mm FR4 PCB, 1oz copper, still air 2
Thermal Resistance, Junction to Lead RJL 197 C/W Note 7: junction to solder point at end of collector lead 2

Materials and finish

As the datasheet states them (page.json metadata.appearance; the 3D model's colours follow it).

Part Material Colour / plating Datasheet says Page
contacts tin  Terminals: Finish, Matte Tin Plated Leads, Solderable per MIL-STD-202, Method 208 1

CAD (KiCad official)

  • Symbol: FMMT491ATA
  • Footprint: Package_TO_SOT_SMD:SOT-23
  • 3D model: SOT-23 (KiCad packages3D, STEP)
  • 3D model files: fmmt491ata-etched.step / fmmt491ata-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); fmmt491ata.step / fmmt491ata.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Diodes Incorporated datasheet (7 pp, sha256 623af61c5133cb8e, retrieved 2026-10-18, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text+vision), consensus claude-opus-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF