Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

Diodes Incorporated FMMT619TA

Name: FMMT619TA
Brand: Diodes Incorporated
SKU: FMMT619TA
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: FMMT619TA

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: FMMT619TA.pdf

Description:: TRANS NPN 50V 2A SOT-23-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:13,708

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

FMMT619TA from Diodes Incorporated is a 50V NPN silicon low-saturation transistor in SOT23 package, rated for 2A continuous collector current, 625mW power dissipation, and V_CE(sat) < 200mV at 1A. It delivers R_CE(sat) = 68mΩ and h_FE up to 450 at 2A, serving as a high-efficiency switch in MOSFET gate-driving and DC-DC converter output stages.

For engineers reviewing the FMMT619TA datasheet, FMMT619TA pinout, FMMT619TA application, or FMMT619TA equivalent, key selection criteria include verified low V_CE(sat) under high-current switching, thermal performance on FR4 PCBs, complementary PNP pairing with FMMT720, and automotive-grade variant availability (FMMT619Q).

Technical Context

This NPN transistor operates with BV_CEO = 50V and supports pulsed I_C up to 6A, enabling robust switching in high-duty-cycle regulator feedback paths. Its h_FE is characterized from 10mA to 6A, ensuring predictable gain behavior across load ranges.

V_BE(sat) = 0.87V (typ) at I_C = 2A / I_B = 50mA and f_T = 165MHz (typ) at I_C = 50mA confirm suitability for fast-switching, medium-power linear and saturated-mode applications where low drive loss and bandwidth matter.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	50V - Maximum safe collector-emitter voltage before breakdown in common-emitter configuration.
I_C (cont)	2A - Continuous collector current rating on 25mm × 25mm FR4 board with 1oz copper, defining steady-state load capacity.
V_CE(sat)	<200mV @ 1A/10mA - Ensures minimal conduction loss and heat generation when fully saturated.
R_CE(sat)	68mΩ - Equivalent on-resistance derived from V_CE(sat)/I_C, critical for efficiency in high-current switching nodes.
h_FE	450 @ 2A - Confirmed DC current gain at full-rated current, supporting stable base drive design without overdesign.
f_T	165MHz - Transition frequency indicating usable bandwidth for moderate-speed switching (e.g., ≤500kHz PWM).
P_D	625mW - Steady-state power dissipation limit on standard PCB layout, setting thermal derating baseline.

Pinout & Package

Package: SOT23 (Type DN), surface-mount plastic package with matte tin-plated leads, UL 94V-0 rated molding compound, and moisture sensitivity level 1.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Reference node for base drive and collector current return; connected to ground or low-side reference in switch configurations.
2 (Base)	Control input	Accepts TTL/CMOS-compatible drive current (≤500mA peak); requires series resistor to limit I_B per h_FE target.
3 (Collector)	Current source terminal	Connects to load or switching node; carries full I_C; thermally coupled to PCB pad via lead (R_θJL = 194°C/W).

Key Features

Feature	Design Value
Low saturation voltage	V_CE(sat) < 200mV @ 1A enables <100mW conduction loss, reducing thermal stress in compact converters.
High current gain hold-up	h_FE ≥ 225 @ 2A ensures reliable saturation with modest base drive, minimizing driver stage complexity.
Complementary PNP pairing	FMMT720 matches V_CEO, I_C, and V_CE(sat) specs, simplifying push-pull and H-bridge layout.
Green construction	Halogen- and antimony-free, RoHS 3-compliant molding compound meets automotive and industrial environmental mandates.

Applications

MOSFET Gate Driving

DC-DC Converter Output Stage

Use Scenario: Driving the gate of a high-side N-channel MOSFET in a synchronous buck converter.

IC Role / Device Role / Timing Role: Low-side NPN switch that pulls the MOSFET gate to ground during turn-off, leveraging fast t_off = 750ns.

Use Value: Low V_CE(sat) minimizes gate discharge loss; 2A I_C rating handles large gate charge (Q_g) without secondary buffering.

Use Scenario: Active freewheeling switch in non-synchronous flyback or boost topologies.

IC Role / Device Role / Timing Role: Saturated-mode power switch replacing Schottky diode to reduce forward drop and improve efficiency.

Use Value: 68mΩ R_CE(sat) cuts conduction loss by >40% vs. typical 0.4V Schottky, directly boosting light-load efficiency.

LED Constant-Current Regulator

Brushed DC Motor Control

Use Scenario: Series-pass element in a linear LED driver with analog dimming.

IC Role / Device Role / Timing Role: Adjustable current sink controlled via base voltage, operating in linear region with thermal foldback.

Use Value: Stable h_FE up to 6A allows precise current regulation across temperature; 150°C max T_J supports enclosed fixture designs.

Use Scenario: H-bridge low-side switch for bidirectional control of small DC motors (e.g., automotive HVAC actuators).

IC Role / Device Role / Timing Role: Fast-switching current path enabling PWM speed control with minimal shoot-through risk.

Use Value: 170ns t_on and 750ns t_off support 20kHz+ PWM without significant dead-time penalty or torque ripple.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN low-saturation transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
ZXTN2012ZTA	V_CEO = 60V, V_CE(sat) = 150mV @ 1A, h_FE = 300 @ 2A - higher voltage rating but lower gain at high current.	Preferred in 48V bus systems where 50V margin is insufficient; less suitable for high-gain base-limited drivers.	Select when system voltage exceeds 45V or when tighter V_CE(sat) tolerance is required.
DMT3006LPSQ-7	V_CEO = 30V, R_DS(on) = 28mΩ (MOSFET), gate-threshold 1.2V - not bipolar, zero gate current, but lower voltage rating.	Better for ultra-low drive power and high-frequency (>1MHz) operation; unsuitable for linear-mode current regulation.	Choose for high-frequency, low-I_Q switching where gate drive simplicity outweighs linear-mode flexibility.

Compared with ZXTN2012ZTA and DMT3006LPSQ-7, FMMT619TA offers optimal balance of 50V rating, 2A current capability, and high h_FE at full load-making it ideal for cost-sensitive, thermally constrained DC-DC and motor-control designs requiring proven bipolar linearity and drive compatibility.

Availability

FMMT619TA is available at Aetrix Electronics and suitable for MOSFET gate driving, DC-DC converter output stages, and brushed DC motor control requiring stable component supply, consistent SOT23 packaging, and RoHS 3-compliant manufacturing.

Supply support for FMMT619TA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

FMMT619TA belongs to Diodes' FMMT series of high-performance SOT23 transistors, engineered specifically for space-constrained power switching applications demanding low saturation loss, high current gain stability, and automotive-grade reliability.

FAQ

What is the maximum allowable junction temperature for FMMT619TA?

The absolute maximum junction temperature is +150°C, with continuous operation supported from –55°C to +150°C ambient. Derating begins at +25°C ambient per Figure 2: power dissipation drops linearly to zero at +175°C case temperature on standard FR4 layout.

Can FMMT619TA replace a small-signal transistor like BC847 in switching applications?

No - FMMT619TA is optimized for 2A switching, not small-signal amplification. Its higher capacitance (C_obo = 12pF) and slower turn-off (750ns) make it unsuitable for RF or high-frequency logic; BC847 remains preferred for signal routing below 100MHz.

Is the SOT23 (Type DN) footprint compatible with standard SOT23 land patterns?

Yes - Diodes specifies SOT23 (Type DN) with standardized dimensions (D = 2.80–3.04mm, E = 2.10–2.64mm) and provides recommended pad layout (C = 2.0×0.8mm). It aligns with IPC-7351B generic SOT23 footprint and fits automated placement equipment.

Does FMMT619TA support linear (analog) operation, or is it strictly for switching?

It supports both: h_FE is characterized up to 6A and V_BE(on) is specified at V_CE = 2V, confirming validated linear-region behavior. Designers use it in constant-current LED sinks and analog feedback loops where gain stability and thermal predictability are essential.

FMMT619TA Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 2 A

Voltage - Collector Emitter Breakdown (Max):: 50 V

Vce Saturation (Max) @ Ib, Ic:: 220mV @ 50mA, 2A

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 200 @ 1A, 2V

Power - Max:: 625 mW

Frequency - Transition:: 165MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3

FMMT619TA FAQ

1.How can I place an order for FMMT619TA through Aetrix?

Please submit a Request for Quotation (RFQ) for FMMT619TA on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for FMMT619TA reliable?

The price and inventory of FMMT619TA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FMMT619TA is usually 5 days.

3.What payment methods are accepted for FMMT619TA?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FMMT619TA transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for FMMT619TA?

FMMT619TA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your FMMT619TA order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for FMMT619TA?

For technical support, including FMMT619TA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FMMT619TA requirements.

6.How does Aetrix verify that FMMT619TA is sourced from the original manufacturer or authorized distributors?

All FMMT619TA products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that FMMT619TA meets industry standards.

7.What is the process for return or replacement of FMMT619TA?

All FMMT619TA units undergo pre-shipment inspection (PSI). If there is an issue with FMMT619TA, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The FMMT619TA part is unused and in its original packaging.

Return procedure for FMMT619TA:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…

2026-08-11 LDO Regulator: Dropout Voltage, Noise, PSRR and Power Dissipation

LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…

2026-08-06 Conditional Access Module: CAM, CI/CI+ and DVB Security

Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…

2026-08-03 Electronic Component Obsolescence: EOL Risks, Replacement Options and Last-Time Buy Strategy

Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.

2026-07-29 18650 Battery: Voltage, Capacity, Charging and Pack Design

18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…

2026-07-27 Hall Effect Sensor: Working Principle, Types, Circuits and Applications

Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…

2026-07-20 Product Change Notification (PCN) in Electronic Components: Meaning and Supply Chain Response

Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…

2026-07-19 Blend Door Actuator: Symptoms, Location, Reset and Replacement Guide

A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…